Ingredient Glossary
Understand What’s Really in the Products You Use
Use this glossary to look up ingredients found in food, beverages, supplements, beauty and personal care, household products, and other everyday items, and understand why Feather & Nest classifies them as Avoid or Use in Moderation.
Ingredient research can get complicated quickly. Feather & Nest looks beyond whether an ingredient is simply considered “safe” or “toxic” and considers what the research shows, how much and how often someone may be exposed, cumulative exposure, potential health effects, individual sensitivities, sourcing and manufacturing practices, and potential contaminants or byproducts. This resource was created to simplify that information so you can better understand what you're being exposed to and make informed choices based on your own health goals, sensitivities, values, and lifestyle.
Inside the glossary, you'll find:
• A simple rating system showing which ingredients Feather & Nest classifies as Avoid or Use in Moderation
• Ingredient descriptions explaining what an ingredient is, why it is used, and what health or exposure concerns may be associated with it
• Potential contaminants and manufacturing concerns, including what may be left behind and why it matters
• Commonly Found In examples to help you recognize where an ingredient may show up
• Source information, including how an ingredient is derived or manufactured
• Pregnancy & Breastfeeding considerations when applicable
• EWG ratings when available
• Articles and study links for deeper research and context
• Information on some ingredients associated with medical products and vaccine manufacturing for additional context on where and how certain ingredients may be used
An ingredient does not have to be inherently “toxic” to be worth understanding. Some ingredients may become a concern depending on how much is consumed or used, how often someone is exposed, the route of exposure, cumulative intake, or certain health conditions and sensitivities. Others may raise questions because of how they are manufactured, processed, sourced, or purified.
Regulatory oversight also varies depending on the type of ingredient and product. An ingredient being legally permitted for use does not necessarily mean it has been individually reviewed and approved by the FDA before reaching the market. Requirements differ between categories such as food, cosmetics, supplements, drugs, and household products. For this reason, Feather & Nest looks beyond whether an ingredient is simply “allowed” and considers the broader evidence and exposure context.
Some ingredients may also have additional concerns depending on how they are sourced, processed, manufactured, or purified. This can include pesticide residues, heavy metals, PFAS, residual solvents or monomers, plasticizers, and manufacturing byproducts such as 1,4-dioxane. These contaminants are not necessarily present in every product, which is why sourcing, manufacturing, purification, and testing can matter.
Important Note About EWG Ratings
EWG uses different rating systems depending on the product category. Beauty and personal care ingredients in the Skin Deep database are generally given a hazard score from 1–10 along with a separate data-availability rating. EWG also offers the EWG VERIFIED designation for products that meet additional standards. Household and cleaning products are evaluated using a different rating system.
A low EWG rating does not automatically mean an ingredient meets the standards used by Feather & Nest, and a higher rating does not tell the entire story on its own. Ingredient safety and exposure can also depend on the amount used, product formulation, manufacturing, potential contamination, exposure route, frequency of use, cumulative exposure, individual health conditions, and sensitivities.
EWG is one helpful research tool, but it is not the final word when Feather & Nest evaluates an ingredient or product.
Rating System
1. Avoid
Ingredients with stronger concerns related to toxicity, endocrine or reproductive effects, carcinogenicity or genotoxicity, harmful contaminants or manufacturing byproducts, respiratory effects, sensitization, environmental persistence, or other concerns that warrant a more precautionary approach.
2. Use in Moderation
Ingredients that may have health concerns depending on the amount consumed or used, frequency of exposure, cumulative intake, individual health conditions, or personal sensitivities. This category may also include concerns related to irritation, sourcing, processing, formulation, manufacturing, potential contaminants, environmental impact, or route of exposure.
An ingredient may also have a different recommendation during pregnancy or breastfeeding when the available evidence supports additional precautions.
Disclaimer
The Feather & Nest Ingredient Glossary is intended for informational and educational purposes only. Feather & Nest does not provide medical advice, and the information in this glossary is not intended to diagnose, treat, cure, or prevent any disease or replace individualized advice from a qualified healthcare professional.
Ingredient research and safety information can change over time. The glossary is based on publicly available research, scientific literature, ingredient databases, regulatory information, safety assessments, and other available evidence and will be reviewed and updated periodically as new information becomes available.
Individual risk can also depend on the amount and route of exposure, frequency of use, product formulation, personal sensitivities, health history, and other factors. Always do your own research and consult a qualified healthcare professional when appropriate.
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A
Acacia Senegal Gum (Gum Arabic)
Use in Moderation
A natural gum made from the sap of Acacia trees, used to thicken, stabilize, and help ingredients mix. Also called gum arabic or acacia gum, it is generally considered low concern when eaten but can cause allergic reactions in some people. Repeatedly breathing in gum arabic powder has also been linked to asthma and other respiratory allergies, making inhalation more of a concern than eating it in food.
Commonly Found In: Food + Beverage (candy, baked goods, beverages, ice cream & packaged foods); Supplements & Medications
Pregnancy & Breastfeeding: Acacia Senegal Gum is generally considered safe during pregnancy when consumed in smaller amounts. It is a natural substance and does not pose significant risks.
Source: Natural
EWG Rating: 3
Acesulfame Potassium (Ace-K)
Use In Moderation
An artificial sweetener used to make foods and drinks taste sweet without adding sugar or calories. Some animal studies have raised concerns about possible gut microbiome and metabolic effects, but these effects haven't been clearly shown in humans. Ace-K is absorbed into the body and can cross the placenta and pass into breast milk.
Commonly Found In: Food + Beverage + Supplements (diet drinks, sugar-free foods, gum, protein powders, drink mixes & flavored supplements)
Pregnancy & Breastfeeding: Ace-K crosses the placenta and passes into breast milk, but current research has not shown that typical dietary exposure causes reproductive or developmental harm
Source: Synthetic
EWG Rating: 1
Acetyl Hexapeptide-8
Use in Moderation
A synthetic peptide commonly used in anti-aging skincare to help soften the appearance of fine lines and wrinkles. Research has raised concerns about skin absorption, effects on cells, and how this ingredient affects nerve signaling, although most of these concerns come from lab studies using higher amounts than typically found in skincare. Some Acetyl Hexapeptide-8 ingredients are also sold in mixtures containing phenoxyethanol and parabens, so what’s used in the final formula can matter.
Commonly Found In: Beauty + Personal Care (anti-aging serums, eye creams, moisturizers & wrinkle treatments)
Pregnancy & Breastfeeding: There isn't enough research on Acetyl Hexapeptide-8 during pregnancy or breastfeeding to know whether repeated use poses a concern.
Source: Synthetic peptide
EWG Rating: 1–2
Acetyl Tetrapeptide-3
Use in Moderation
A synthetic peptide commonly used in hair-growth and anti-aging products. Lab studies found that higher amounts reduced the number of healthy skin and hair-follicle cells and their ability to grow normally. The concentrated ingredient can also irritate the skin and eyes, and there is still limited safety research on repeated use.
Commonly Found In: Beauty + Personal Care (hair-growth serums, scalp treatments, lash and brow products & anti-aging skincare)
Pregnancy & Breastfeeding: There isn't enough research during pregnancy or breastfeeding to know whether repeated use poses a concern
Source: Synthetic
EWG Rating: 1
Acid Protease
Use in Moderation
An enzyme that helps break down protein and is commonly made through fermentation using fungi such as Aspergillus. The finished enzyme isn't the same as mold, but allergic reactions are possible, especially when enzyme powders are breathed in. Because some fungi can produce unwanted toxins during fermentation, how the enzyme is made, purified, and tested also matters.
Commonly Found In: Food + Beverage + Supplements (digestive enzymes, protein-processing aids, brewing & other processed foods)
Pregnancy & Breastfeeding: There isn't enough research specifically during pregnancy or breastfeeding to know whether regular supplemental use poses a concern
Source: Can be natural (from mold)
EWG Rating: N/A
Acrylates Copolymer
Use in Moderation
A synthetic polymer used to thicken products, create a film, and help makeup, sunscreen, and hair products stay in place. The finished polymer itself is considered lower-concern, but how it is made is worth knowing about. Small amounts of leftover chemicals from manufacturing may remain, including acrylic acid, methacrylic acid, methyl methacrylate, ethyl acrylate, and other acrylate monomers. These residual chemicals can irritate the skin, eyes, or lungs, and some acrylates can cause allergic skin reactions. The amount left behind depends on how well the ingredient is manufactured and purified.
Commonly Found In: Household + Beauty (mascara, nail adhesives, hair styling products, and sunscreen)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established for Acrylates Copolymer at typical cosmetic use levels. Use in moderation, especially with sprays or products that may be inhaled.
Source: Synthetic
EWG Rating: 1-2 depends on usage
Acrylates/C10-30 Alkyl Acrylate Crosspolymer
Use in Moderation
A synthetic polymer used to thicken and improve the texture of skincare and beauty products. The ingredient itself is considered lower concern, but how it is made is the bigger issue. Depending on the manufacturing process, it may contain residual benzene, n-hexane, cyclohexane, ethyl acetate, acrylic acid, or acrylate monomers. Benzene is a known carcinogen linked to leukemia and other blood cancers, while n-hexane can damage the nervous system with higher or repeated exposure. Other residual solvents and monomers may irritate the skin, eyes, or lungs. These contaminants are not necessarily present in every product, which is why manufacturing and purity testing matter.
Commonly Found In: Beauty (moisturizers, baby lotions, sunscreens, hair styling products)
Pregnancy & Breastfeeding: There is no evidence that the finished polymer causes reproductive or developmental harm. The relevant concern is manufacturing contaminants, which can vary by supplier
Source: Synthetic
EWG Rating: 1-2
Acrylic Acid Homopolymer
Use in Moderation
A synthetic polymer that mainly works as a binder, emulsion stabilizer, and film former. It helps hold product ingredients together and improves texture and performance. Generally considered low toxicity to humans, though it can cause skin, eye, or respiratory irritation if handled as a powder. The bigger concern is environmental, as it is not readily biodegradable and may persist in waterways.
Commonly Found In: Cleaning products, cosmetics, adhesives, detergents
Pregnancy & Breastfeeding: Generally safe in household use, but avoid inhaling dust.
Source: Synthetic (petroleum-derived)
EWG Rating: N/A
Acrylates/Ammonium Methacrylate Copolymer
Use in Moderation
A synthetic polymer that improves texture and helps products stay in place. The main concern is leftover manufacturing chemicals, including acrylic acid and methacrylic acid, which can irritate the skin and eyes. Benzene, a known carcinogen, may also be a concern with certain manufacturing methods. Better manufacturing and purification help reduce these contaminants.
Commonly Found In: Makeup, sunscreen, moisturizers, cleansers, and other personal care products
Pregnancy & Breastfeeding: Limited safety data; no evidence of reproductive or developmental harm from the finished polymer
Source: Synthetic
EWG Rating: 2
Acrylic Acid
Avoid
A synthetic chemical used to make adhesives, coatings and acrylic-based ingredients. It can irritate or damage the skin and eyes, and breathing higher amounts can irritate the respiratory system. Acrylic acid can also remain as a leftover chemical when acrylic polymers are manufactured.
Commonly Found In: Beauty + Personal Care (especially nail glue, plus some eyelash glue, nail products, makeup and hair products)
Pregnancy & Breastfeeding: Limited human data; EWG currently lists developmental and reproductive toxicity as low concern
Source: Synthetic
EWG Rating: 3
Acrylic Polymer
Avoid
A general term for synthetic polymers used to bind ingredients together, create a film, improve texture, or make products more water-resistant. The finished polymer itself may be less of a concern, but some acrylic polymers can contain leftover acrylate monomers from manufacturing. These may include chemicals such as ethyl acrylate, acrylic acid, methacrylic acid, or other acrylates, depending on the specific polymer. Some acrylates can irritate the skin, eyes, and lungs or trigger allergic skin reactions, and certain starting materials have raised cancer concerns. Synthetic acrylic polymers also break down slowly in the environment.
Commonly Found In: Household + Beauty (adhesives, paints, coatings, nail products, makeup, sunscreens, hair products)
Pregnancy & Breastfeeding: Avoid when possible, especially in products you can inhale. The main concern is potential leftover chemicals from manufacturing rather than the finished polymer itself.
Source: Synthetic (plastic-based polymer)
EWG Rating: N/A
Active Yeast
Use in Moderation
A live yeast, usually Saccharomyces cerevisiae, commonly used to help bread and other baked goods rise. It is generally considered low concern in normal food amounts. Rare allergic reactions can occur, and live Saccharomyces has caused infections in people who are severely ill or immunocompromised, particularly with probiotic use rather than baked foods. Some commercially produced yeast strains are genetically modified, but this isn't disclosed simply by the ingredient name “active yeast,” so sourcing matters if you're trying to avoid GMO ingredients.
Commonly Found In: Food + Beverage (bread, pizza dough, rolls and other baked goods) + Supplements (some probiotics)
Pregnancy & Breastfeeding: Generally considered safe in normal food amounts. Avoid it if you have a known yeast allergy.
Source: Natural fermentation-derived; some strains may be genetically modified
EWG Rating: N/A
Agar
Use in Moderation
A thickener and gelling ingredient made from red seaweed. Agar itself is considered fairly low concern, but sourcing and testing matter because seaweed can pick up heavy metals such as arsenic, lead and cadmium from the environment. The amount can vary depending on where the seaweed was grown and how the ingredient was processed and tested. Larger amounts of agar can also absorb a lot of water and swell, which may cause choking or intestinal blockage if taken without enough liquid.
Commonly Found In: Food + Beverage + Supplements (gummies, desserts, jellies, dairy alternatives, thickened foods, fiber and laxative products)
Pregnancy & Breastfeeding: Generally considered low concern in normal food amounts. Larger amounts used as a fiber or laxative have less pregnancy-specific research, so use in moderation and with plenty of water
Source: Natural (red seaweed-derived)
EWG Rating: N/A
Agave (Agave Nectar/Agave Syrup)
Use in Moderation
A sweetener made from the agave plant and commonly used as an alternative to sugar. Although it comes from a plant, agave syrup is highly processed and especially high in fructose. Agave plants also naturally contain compounds called saponins, some of which have raised concerns about stimulating uterine contractions. Commercial agave syrup is processed and likely contains much lower amounts of these plant compounds, so it isn't clear whether this concern applies to normal amounts of agave syrup.
Commonly Found In: Food + Beverage (sweeteners, syrups, drinks, desserts, snack bars and packaged foods)
Pregnancy & Breastfeeding: Use in moderation. Agave plants contain compounds that have raised concerns about uterine stimulation, but there isn't good evidence showing that normal amounts of commercially processed agave syrup cause contractions or pregnancy complications.
Source: Plant-derived and processed
EWG Rating: N/A
Alcohol Denat. (Denatured Alcohol)
Use in Moderation (Depending on Denaturant and Product Type)
Denatured alcohol is ethanol (ethyl alcohol) with another ingredient added to make it unsuitable for drinking. It may appear on labels as Alcohol Denat., SD Alcohol, or specially denatured alcohol followed by a number or letter combination. The concern isn't simply that the alcohol is denatured, but what was added to it. Denaturants can include bittering agents, other chemicals, or certain essential oils, and their potential health concerns vary. The label doesn't always identify which one was used.
Alcohol also evaporates quickly and can dry or irritate the skin with frequent use. It can temporarily disrupt the skin's protective barrier, and people may inhale vapors or fine droplets when products are sprayed. Without a disclosed denaturant, the full formula cannot be properly evaluated. Products with clearly identified, appropriately assessed denaturants may be reasonable for their intended use, while those with undisclosed or concerning denaturants warrant additional caution.
Commonly Found In: Beauty + Personal Care (hand sanitizers, toners, serums, sunscreens, setting sprays, perfumes, and hair products)
Pregnancy & Breastfeeding: Typical topical exposure is different from drinking alcohol. Consider repeated use, skin irritation, and inhalation exposure, particularly with sprays.
Source: Ethanol with added denaturing ingredients; ethanol may be naturally derived or synthetic
EWG Rating: 1
Alkyl C12-14 Dimethylethylbenzyl Ammonium Chloride
Avoid
A quaternary ammonium compound, or “quat,” used to kill bacteria and disinfect surfaces. Concentrated forms can damage the skin and eyes and can be harmful if swallowed or absorbed through the skin. Repeated exposure to disinfectant quats has also raised concerns about respiratory irritation and asthma, particularly when products are sprayed or frequently inhaled. Animal and laboratory research on quats as a group has raised additional questions about reproductive and developmental effects, although these effects have not been established in humans from typical household exposure. Quats are also highly toxic to aquatic life.
Commonly Found In: Household (disinfecting sprays and wipes, antibacterial cleaners, sanitizers and other disinfectants)
Pregnancy & Breastfeeding: Avoid unnecessary exposure when possible, particularly sprays and concentrated products. Research on quats has raised reproductive and developmental concerns, but human pregnancy data for this specific ingredient is limited.
Source: Synthetic (quaternary ammonium compound)
EWG Rating: 5
Alkyl C12-18 Dimethylbenzyl Ammonium Chloride
Avoid
A quaternary ammonium compound, or “quat,” used to kill bacteria and disinfect surfaces. It can irritate the skin and eyes and is also linked to asthma and respiratory sensitivity. Animal studies on some commonly used quats have also found reduced fertility and other reproductive effects.
Commonly Found In: Household (disinfecting sprays, wipes, bathroom cleaners and antimicrobial cleaners)
Pregnancy & Breastfeeding: Avoid when possible, especially sprays that can be inhaled. Animal research has raised concerns about reproductive effects from some quats, but human pregnancy research is limited.
Source: Synthetic
EWG Rating: N/A
Alkyl Dimethyl Amine Oxides (C10-16)
Use in Moderation
A surfactant used to help lift grease and dirt and create foam in cleaning and personal care products. It is generally considered a lower health concern, although it can irritate the skin and eyes, especially with concentrated products. It is also highly toxic to aquatic life, making frequent or high-volume use an environmental concern.
Commonly Found In: Beauty + Household (shampoos, conditioners, dish soaps, household cleaners)
Pregnancy & Breastfeeding: Generally considered lower concern in typical product use. Use in moderation if skin is sensitive or easily irritated.
Source: Synthetic
EWG Rating: 1
Alkylphenol Ethoxylates (APEs)
Avoid
A group of surfactants used to help remove grease and help ingredients mix together. Some APEs, particularly nonylphenol ethoxylates, can break down into chemicals such as nonylphenol that can interfere with normal hormone activity. These breakdown products can also persist in the environment, build up in aquatic life, and are highly toxic to aquatic organisms. Animal studies on nonylphenol have also raised reproductive and developmental concerns.
Commonly Found In: Household + Industrial Products (cleaners, detergents, paints, coatings, degreasers and some personal care products)
Pregnancy & Breastfeeding: Avoid when possible. Animal research on nonylphenol has raised reproductive and developmental concerns, although human pregnancy research is limited.
Source: Synthetic
EWG Rating: N/A
Allulose
Use in Moderation
A “rare” sugar found naturally in very small amounts but usually manufactured for use in foods. Larger amounts can cause bloating, stomach pain, nausea, and diarrhea. It can also be made from corn-derived sugars, so sourcing matters if you're trying to avoid GMO ingredients. Choosing USDA Organic or verified non-GMO options can help with this.
Commonly Found In: Food + Beverage (low-sugar foods, protein bars, baked goods, drinks, keto products, sweeteners)
Pregnancy & Breastfeeding: Human research is limited. Use in moderation, especially if it causes digestive issues.
Source: Naturally occurring, but commercially manufactured; can be made from corn-derived sugars
EWG Rating: N/A
Alpha-Isomethyl Ionone
Avoid
A fragrance ingredient used to add a floral scent to beauty and household products. It is a known skin allergen and can cause irritation or allergic reactions, especially if you have sensitive skin or are regularly exposed to fragranced products.
Commonly Found In: Beauty + Household (perfume, lotions, skincare, hair products, soaps, detergents, fabric softeners, air fresheners)
Pregnancy & Breastfeeding: The main established concern is skin allergy and sensitivity rather than reproductive or developmental toxicity.
Source: Can be naturally occurring or synthetically produced
EWG Rating: 3
Alumina
Avoid
A form of aluminum used in cosmetics to absorb moisture, prevent clumping, add texture, or provide gentle abrasion. Concern depends on how it is used, with greater concern when fine particles can be inhaled. It has also been associated with allergy and immune-related concerns. Risk can vary depending on the form, particle size, and type of product.
Commonly Found In: Beauty + Personal Care (powders, makeup, deodorants, sunscreens and exfoliating products)
Pregnancy & Breastfeeding: Human pregnancy data is limited. Avoid inhalable forms such as loose powders or sprays where fine particles can be breathed in.
Source: Mineral-derived or synthetic aluminum oxide
EWG Rating: 3-7
Aluminum
Avoid
A naturally occurring metal used in many different forms in cookware, food packaging, antiperspirants, medications, and other everyday products. The concern depends heavily on the form of aluminum, dose, and route of exposure. Higher levels of aluminum can build up in the body and affect the nervous system, bones, and other organs, although normal everyday exposure has not been proven to cause diseases such as Alzheimer's. Exposure may also increase when aluminum cookware or foil comes in contact with hot, acidic, or salty foods, which can increase leaching.
Commonly Found In: Household + Food & Beverage + Medical Products (Cookware, aluminum foil, food packaging, antiperspirants, canned foods, some vaccine adjuvants)
Pregnancy & Breastfeeding: Limiting unnecessary cumulative exposure to aluminum may be a reasonable precaution, especially from food-contact materials and frequently used products.
Source: Natural (but processed)
EWG Rating: N/A
Aluminum Hydroxide
Use in Moderation
A form of aluminum used in cosmetics to help with color, texture, and product stability. High enough levels of aluminum in the body can affect the nervous system, bones, and other organs, but aluminum hydroxide is poorly absorbed through the skin, so exposure from typical cosmetic use is expected to be low. If you use several aluminum-containing products regularly, this may still be an ingredient you choose to limit as part of reducing your overall aluminum exposure.
Commonly Found In: Beauty (concealer, lipstick, brow products, eyeshadow, sunscreen and other cosmetics)
Pregnancy & Breastfeeding: Use in moderation if you're trying to minimize unnecessary cumulative aluminum exposure. Current research does not show a developmental risk from typical cosmetic exposure.
Source: Manufactured aluminum compound
EWG Rating: 2
Ammonia
Avoid
A strong chemical used in cleaning products and some hair dyes. The fumes can irritate the eyes, skin, throat, and lungs, especially with concentrated products or in poorly ventilated areas. Higher exposure can cause coughing, chest tightness, and difficulty breathing. Higher concentrations can cause serious chemical burns and lung damage, while repeated exposure can contribute to ongoing respiratory irritation.
Commonly Found In: Household + Beauty (glass cleaners, degreasers, floor cleaners, hair dyes)
Pregnancy & Breastfeeding: Avoid unnecessary exposure, especially fumes from concentrated products or use in poorly ventilated areas.
Source: Naturally occurring compound that is also manufactured commercially
EWG Rating: N/A
Ammonium Bicarbonate
Use in Moderation
Also known as baker’s ammonia, this ingredient helps baked goods rise and become crispy. While it is considered a fairly low concern on its own, it can increase acrylamide formation when certain foods are baked at high temperatures. Acrylamide is an unwanted byproduct that forms during high-heat cooking and has been linked to cancer concerns.
Commonly Found In: Food + Beverage (cookies, crackers, biscuits, and other crispy baked goods)
Pregnancy & Breastfeeding: Use in moderation to help limit unnecessary exposure to acrylamide from processed and heavily browned foods.
Source: Synthetic/manufactured
EWG Rating: 2
Ammonium Chloride
Use in Moderation
A salt made from ammonia and hydrochloric acid used to adjust pH, thicken products, and for other functional purposes. It can irritate the eyes and respiratory tract, especially as a powder or with higher exposure. Larger amounts taken internally can also disrupt the body's acid-base balance and become harmful.
Commonly Found In: Beauty + Food & Beverage + Supplements (shampoos, cleansers, some processed foods, electrolyte products, supplements, medications)
Pregnancy & Breastfeeding: Use in moderation. There isn't strong evidence of reproductive or developmental toxicity from typical exposure, but supplements or medications containing it should be used as directed.
Source: Synthetic/manufactured inorganic salt
EWG Rating: 3
Ammonium Hydroxide
Avoid
Ammonia dissolved in water and used to adjust pH or help products work properly. It can irritate the skin, eyes, and lungs, especially when inhaled as fumes. Stronger concentrations can also cause chemical burns, making the amount and type of exposure important.
Commonly Found In: Beauty + Household (hair dyes, some makeup and skincare products, cleaners, floor strippers)
Pregnancy & Breastfeeding: Avoid unnecessary exposure, especially concentrated products or fumes that can be inhaled.
Source: Synthetic/manufactured (ammonia dissolved in water)
EWG Rating: 2–6
Ammonium Laureth Sulfate (ALES)
Avoid
A cleansing and foaming ingredient made through ethoxylation, a process that uses ethylene oxide. It can irritate the skin and eyes, but the bigger concern is possible contamination from manufacturing. ALES may contain trace ethylene oxide and 1,4-dioxane if it isn't properly purified. Both are linked to cancer, and because they're contaminants rather than intentionally added ingredients, you won't normally see them listed on the label.
Commonly Found In: Beauty + Household (shampoos, body washes, hand soaps, bubble baths, dish soaps, cleaning products)
Pregnancy & Breastfeeding: Avoid when possible, to reduce unnecessary exposure to ethoxylated ingredients and possible manufacturing contaminants.
Source: Synthetic/processed (ethoxylated surfactant)
EWG Rating: 1–2
Ammonium Lauryl Sulfate (ALS)
Use in Moderation
A cleansing and foaming ingredient used to remove dirt and oil. It can be irritating and drying to the skin and eyes, especially with frequent use or in stronger formulas. Unlike Ammonium Laureth Sulfate, ALS is not ethoxylated, so the same 1,4-dioxane contamination concern doesn't apply.
Commonly Found In: Beauty + Household (shampoos, body washes, facial cleansers, hand soaps, dish soaps, cleaning products)
Pregnancy & Breastfeeding: Use in moderation. There aren't strong reproductive or developmental concerns with typical use.
Source: Processed surfactant; can be made from plant- or petroleum-derived ingredients depending on sourcing
EWG Rating: 1
Amyloglucosidase
Use in Moderation
An enzyme that breaks down starches into simple sugars. It is commonly produced through fermentation using microorganisms such as Aspergillus niger. The finished enzyme is not the same as the mold used to produce it, but enzymes can cause allergic reactions or respiratory sensitization in some people, particularly when concentrated enzyme powders or aerosols are repeatedly inhaled.
Commonly Found In: Food + Beverage + Supplements (processed foods, baking, brewing, digestive enzyme supplements)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established from typical food exposure
Source: Fermentation-derived (commonly produced using Aspergillus niger)
EWG Rating: 2
Annato
Use in Moderation
A natural food coloring made from achiote seeds that gives foods a yellow, orange, or red color. Annatto itself is considered relatively low concern, but some people can experience allergic reactions or digestive symptoms. Some annatto extracts are also made using solvents such as hexane, acetone, or methanol, making processing and purity important considerations. When possible, look for USDA Organic annatto and brands that are transparent about how their ingredients are sourced and processed.
Commonly Found In: Food + Beverage (cheese, butter, snacks, cereals, baked goods, sauces, processed foods)
Pregnancy & Breastfeeding: Use in moderation, especially in highly processed foods where sourcing and processing aren't clear.
Source: Natural (from achiote seeds, but commercially processed)
EWG Rating: N/A
Artificial Flavors (Unidentified)
Avoid
A broad term for synthetic flavoring substances added to foods and drinks to create or enhance flavor. The label may simply say “artificial flavor” without identifying every flavoring chemical used, making it difficult to know exactly what is in the mixture. Some individual flavoring chemicals have raised health concerns. For example, estragole, a flavoring substance used to create an anise or licorice-like flavor, has raised concerns about DNA damage and cancer based largely on animal and laboratory research. Not every artificial flavor is harmful, but when the individual chemicals aren't disclosed, it's difficult to evaluate exactly what you're being exposed to.
Commonly Found In: Food + Beverage + Supplements (processed foods, candy, flavored drinks, protein powders, electrolyte mixes, baked goods, snacks)
Pregnancy & Breastfeeding: Avoid when possible to reduce unnecessary exposure to undisclosed additives.
Source: Synthetic
EWG Rating: 4
Ascorbic Acid
Use in Moderation
A form of vitamin C naturally found in foods and also added to foods, drinks, and supplements. Ascorbic acid itself is generally considered low concern, but high supplemental amounts can cause diarrhea, nausea, or stomach cramps and may increase kidney stone risk in some people. Another concern is certain beverages that contain both ascorbic acid and preservatives such as sodium or potassium benzoate. Under certain conditions, especially exposure to heat or light, this combination can form small amounts of benzene, a known carcinogen.
Commonly Found In: Food + Beverage + Supplements (fortified foods, flavored drinks, juices, supplements, processed foods)
Pregnancy & Breastfeeding: Generally considered safe in normal amounts. Avoid taking high doses unless recommended by your healthcare provider.
Source: Natural or synthetic/manufactured
EWG Rating: 1
Ascorbyl Palmitate (Vitamin C Palmitate)
Use in Moderation
A fat-soluble form of vitamin C used as an antioxidant to help keep foods and skincare products from breaking down. It is generally considered low concern, but some lab research suggests that exposure to UVB light may increase damage to skin cells. We don't know if this happens with normal skincare use, but it is something to consider in products that are regularly worn in the sun.
Commonly Found In: Food + Beverage + Supplements + Beauty (processed foods, vitamins, moisturizers, makeup, anti-aging products, sunscreens)
Pregnancy & Breastfeeding: Generally considered low concern in normal amounts. There aren't known reproductive or developmental concerns with typical use.
Source: Processed (vitamin C combined with palmitic acid)
EWG Rating: 2
Aspartame
Avoid
An artificial sweetener commonly used in sugar-free and low-calorie foods and drinks. Research has raised concerns about long-term use. In 2023, the International Agency for Research on Cancer classified aspartame as “possibly carcinogenic to humans” after studies found a possible link to liver cancer. Other research has found possible links to heart disease, stroke, changes in gut bacteria, and effects on brain function, but these findings are still being studied and don't prove that aspartame directly causes these conditions.
**People with PKU (phenylketonuria), a genetic condition that prevents the body from properly breaking down phenylalanine, need to avoid or strictly limit aspartame because phenylalanine can build up to harmful levels in the body.
Commonly Found In: Food + Beverage + Supplements (diet soda, sugar-free gum, drink mixes, candy, flavored foods, chewable vitamins)
Pregnancy & Breastfeeding: One study found that boys whose mothers reported consuming about one diet soda a day, or a similar amount of aspartame, during pregnancy or breastfeeding were about three times more likely to be diagnosed with autism.
Source: Synthetic
EWG Rating: 2
Avobenzone
Avoid
A synthetic sunscreen ingredient used to protect the skin from UVA rays. Avobenzone can be absorbed through the skin and has been found in the bloodstream after sunscreen use. It can also become unstable and break down when exposed to sunlight, creating other chemicals in the process. Animal studies have found changes in thyroid hormones after exposure, raising concerns about possible hormone effects. Research has also found that avobenzone can react with chlorine in swimming pool water and create additional chemicals, some of which may be harmful.
Commonly Found In: Beauty (fragrance, moisturizers, SPF)
Pregnancy & Breastfeeding: Human research during pregnancy and breastfeeding is limited. Because avobenzone is absorbed into the body and animal research has raised hormone concerns, exposure during pregnancy may be a concern
Source: Synthetic
EWG Rating: 1-2
B
2-Butoxyethanol
Avoid
solvent commonly used in conventional cleaners, degreasers, glass cleaners, paints, and other household products. It can enter the body by breathing in the fumes or through the skin, especially with frequent use. Higher exposure can irritate the eyes and airways and cause headaches, nausea, and damage to red blood cells. Animal studies have also found effects on the liver and kidneys, and long-term studies found certain tumors in mice. Humans appear to be less sensitive to some of these effects than animals, but repeated exposure is still a concern.
Commonly Found In: Household (all-purpose cleaners, degreasers, window cleaner)
Pregnancy: Animal studies have found effects on reproduction and development at higher exposures, although many occurred at amounts that also made the mother sick
Source: Synthetic (petroleum-derived).
EWG Rating: 8
Basic Blue 3
Avoid
A synthetic blue dye used mainly in hair coloring products. It has raised cancer concerns and is prohibited for use in cosmetics in the European Union. It can also irritate the eyes. Because of the safety concerns and restrictions surrounding this dye, its use in personal care products is limited or prohibited in some places.
Commonly Found In: Beauty (hair dyes, shampoo)
Pregnancy & Breastfeeding: Avoid—potential carcinogenicity and lack of safety data
Source: Synthetic (coal-tar–derived)
EWG Rating: 5
Basic Blue 99
Avoid
A synthetic blue dye used mainly in temporary and semi-permanent hair color. Recent safety reviews found concerns that Basic Blue 99 may damage genetic material, and it is also considered a skin sensitizer, meaning repeated exposure may trigger an allergic reaction. Another concern is that the ingredient can contain a mixture of many different substances, and its exact makeup has varied between batches, making its safety harder to predict. In 2026, European safety experts concluded that Basic Blue 99 was not considered safe for use at 1% in non-oxidative hair dye.
Commonly Found In: Beauty (hair dyes, conditioners) + Household (textiles)
Pregnancy & Breastfeeding: Avoid—limited safety data and potential carcinogenic risks.
Source: Synthetic
EWG Rating: 4
Behentrimonium Chloride
Avoid
A type of quat commonly used in conditioners and other hair products to reduce static, help with tangles, and make hair feel smoother. In concentrated amounts, it can irritate the skin and eyes, and there are also concerns about breathing problems and allergic reactions. It is also very toxic to aquatic life and can have long-lasting effects once it enters waterways.
Commonly Found In: Beauty + Personal Care (conditioners, hair masks, detanglers, leave-in treatments, shampoos, lotions, and styling products)
Pregnancy: There is limited research on pregnancy however this may cause irritation
Source: Synthetic
EWG Rating: 6
Behentrimonium Methosulfate
Avoid
Despite the name, this is not a sulfate like SLS or SLES. It is a type of quat commonly used in conditioners and other hair products to help with tangles, reduce static, and make hair feel smoother. In concentrated amounts, it can irritate the skin and seriously irritate the eyes. It is also very toxic to aquatic life and can have long-lasting effects once it enters waterways.
Commonly Found In: Beauty (conditioners, hair masks, detanglers, styling creams, shampoos, moisturizers)
Pregnancy & Breastfeeding: Avoid when possible as a precaution. Reproductive concerns have been raised for quats as a group, but there is no strong evidence showing that Behentrimonium Methosulfate itself causes reproductive or developmental harm at typical cosmetic exposure levels.
Source: Synthetic (quaternary ammonium compound)
EWG Rating: 3
Benzophenone
Avoid
A synthetic ingredient used in some personal care products to help keep them from breaking down when exposed to sunlight. Long-term animal studies have linked benzophenone to certain cancers, and it is listed under California Proposition 65 for cancer. Animal studies during pregnancy have also found lower birth weights and slightly delayed bone development at higher exposures. Benzophenone can also pass from the mother to the baby during pregnancy.
Commonly Found In: Beauty + Personal Care + Household (lotions, soaps, body washes, nail polish, cosmetics, scented air fresheners, and some food packaging)
Pregnancy & Breastfeeding: Benzophenone can pass from the mother to the baby during pregnancy. Studies have also found lower birth weights and slightly delayed bone development at higher exposures.
Source: Synthetic
EWG Rating: 3
Benzalkonium Chloride
Avoid
A quaternary ammonium compound (quat) used as a disinfectant, preservative, and surfactant in household cleaners and personal care products. It boosts shine and controls microbial growth but is known to cause skin, eye, and respiratory irritation. Repeated exposure has been linked to contact dermatitis, antibiotic resistance, and hormonal disruption. It is also toxic to aquatic life.
Commonly Found In: Household (surface disinfectants, antibacterial wipes, hand sanitizers), Beauty (some eye drops, nasal sprays, liquid hand soaps, sanitizers)
Pregnancy & Breastfeeding: Avoid—linked to irritation and potential endocrine disruption
Source: Synthetic
EWG Rating: 6
Benzothiazolinone (BIT)
Avoid
A preservative used to prevent bacteria and mold from growing in household products. It is a known skin sensitizer that can trigger allergic contact dermatitis, and rates of allergy to it have been increasing. It can be especially problematic with repeated exposure and for people who are already sensitive to it. BIT is commonly used in household products like cleaners and detergents and is not allowed as a preservative in cosmetics in the European Union.
Commonly Found In: Household (laundry detergents, dish soaps, household cleaners, paints, adhesives and other water-based products)
Pregnancy & Breastfeeding: No well-established pregnancy-specific risk, but limiting exposure can help reduce irritation and sensitization
Source: Synthetic
EWG Rating: 6
Benzoic Acid
Use In Moderation
A preservative used to help prevent bacteria, yeast, and mold from growing in food, personal care, and household products. Concentrated amounts can irritate the skin and eyes, and breathing it in from sprays or powders may irritate the airways. In certain foods and drinks, benzoic acid or benzoates can also react with vitamin C and form small amounts of benzene, especially when exposed to heat and light. Benzene is a known carcinogen linked to leukemia and other blood disorders.
Commonly Found In: Food + Beverage + Beauty + Household (drinks, packaged foods, shampoos, lotions, skincare, cleaners, and laundry products)
Pregnancy & Breastfeeding: Use in moderation, especially in foods and drinks that also contain vitamin C
Source: Synthetic
EWG Rating: 1-2
Benzophenone-1
Avoid
A synthetic ingredient used in cosmetics to help protect products from breaking down when exposed to UV light. Research has found that it can act like estrogen in the body and may interfere with other hormones, including male and thyroid hormones. There are also concerns that it may damage DNA. In 2025, European safety experts concluded that Benzophenone-1 was not considered safe for use at up to 2% in cosmetics because of these concerns.
Commonly Found In: Beauty + Personal Care (nail polish, nail treatments, lip products, fragrances, and some skincare)
Pregnancy & Breastfeeding: Avoid due to concerns about hormone disruption and possible DNA damage
Source: Synthetic
EWG Rating: 4
Benzoyl Peroxide
Avoid
A synthetic acne treatment used to kill acne-causing bacteria and help clear clogged pores. It can dry and irritate the skin, but another concern is benzene, a known human carcinogen linked to leukemia and other blood cancers. Testing has found that benzoyl peroxide can break down and form benzene, particularly when products are exposed to higher temperatures or certain storage conditions. This does not mean every benzoyl peroxide product contains unsafe amounts of benzene, but heat, storage, formulation, and product testing matter.
Commonly Found In: Beauty + Personal Care (acne cleansers, creams, gels, spot treatments)
Pregnancy & Breastfeeding: Topical benzoyl peroxide itself is considered an option for treating acne during pregnancy. The concern here is possible benzene formation in the product, especially with heat and longer storage
Source: Synthetic
EWG Rating: 6
Benzyl Acetate
Use in Moderation
A synthetic or naturally occurring fragrance ingredient used to give products a sweet, floral scent. Benzyl Acetate can be inhaled when fragranced products are sprayed or used in the air. At higher exposures, it can irritate the eyes and respiratory system and affect the central nervous system, causing symptoms such as dizziness and drowsiness. Animal studies have also found nervous system effects at very high doses, although these exposures are much higher than those typically found in beauty or household products.
Commonly Found In: Household + Beauty (air fresheners, cleaners, facial cleansers, shampoo, perfume)
Pregnancy & breastfeeding: Use in moderation due to nervous system and respiratory effects
Source: Synthetic
EWG Rating: 1
Benzyl Alcohol
Use in Moderation
A synthetic ingredient used as a preservative, solvent, and to add fragrance. It can cause skin, eye, or lung irritation, especially in leave-on products or for sensitive skin.
Commonly Found In: Household (cleaners) & Beauty (lotions, toners, toothpaste, perfume)
Pregnancy & Breastfeeding: Use in moderation, especially if your skin is more sensitive during or after pregnancy
Source: Synthetic
EWG Rating: 4
Benzyl Benzoate
Avoid
A fragrance ingredient and solvent commonly used in perfumes and personal care products. It can irritate the skin and cause allergic reactions in some people. Very high amounts can also affect the nervous system, causing symptoms like dizziness, poor coordination, tremors, or seizures. Lab research has found that Benzyl Benzoate can act like estrogen in cells, raising concerns about possible hormone effects. It may also be used alongside other hormone-active fragrance chemicals, making repeated exposure from multiple products another consideration.
Commonly Found In: Beauty + Personal Care + Household (perfumes, lotions, hair products, skincare, soaps, detergents, and other fragranced products)
Pregnancy & Breastfeeding: Avoid when possible because of the possible hormone effects and repeated exposure from fragranced products.
Source: Naturally occurring or synthetic
EWG Rating: 4
Benzalkonium Chloride (BAK)
Avoid
A type of quat used to kill germs and preserve products. It can irritate the skin, eyes, and lungs and can trigger allergic reactions, especially in people with sensitive skin, eczema, or asthma. Frequent use of disinfectants containing BAK may also contribute to bacteria becoming harder to kill with certain disinfectants and antibiotics.
Commonly Found In: Beauty + Household (( Soaps, cleansers, lotions, and deodorants)
Pregnancy & Breastfeeding: Avoid when possible. Animal studies on quaternary ammonium disinfectants have found reproductive concerns, although strong evidence does not show that typical BAK exposure causes reproductive or developmental harm in humans.
Source: Synthetic
EWG Rating: 6
Benzyl Nicotinate
Use In Moderation
A synthetic ingredient used to increase blood flow near the skin, which creates a temporary warming and reddening effect. It can irritate the skin and seriously irritate the eyes, especially at higher amounts.
Commonly Found In: Beauty + Personal Care (lip plumpers, warming creams, muscle products, and some skincare)
Pregnancy & Breastfeeding: Use in moderation, especially in products used frequently or over larger areas of the body
Source: Synthetic
EWG Rating: 1
Benzyl Salicylate
Avoid
A fragrance ingredient used to add a sweet, floral scent and help fragrance last longer. It is a known fragrance allergen that can cause allergic skin reactions. Lab studies have also found that Benzyl Salicylate can act like estrogen, and studies have found hormone-related effects. In another animal study, exposure during pregnancy was linked to lower offspring weight, while higher amounts caused pregnancy loss and birth defects.
Commonly Found In: Beauty + Personal Care + Household (perfumes, shampoos, conditioners, lotions, sunscreens, detergents, and air fresheners)
Pregnancy & Breastfeeding: Avoid due to hormone-related concerns and developmental effects found in animal studies.
Source: Synthetic
EWG Rating: 4
Benzylparaben
Avoid
A synthetic preservative used to help prevent bacteria, mold, and yeast from growing in products. Studies have found that Benzylparaben can act like estrogen. In animal studies, exposure increased uterine weight, a sign of estrogen-like activity, and lab studies have also found that it can activate estrogen receptors. The European Union prohibits Benzylparaben in cosmetics, and U.S. cosmetic safety experts have said there isn't enough information available to determine that it is safe for cosmetic use.
Commonly Found In: Beauty + Personal Care (cosmetics, lotions, skincare, soaps, and other preserved products)
Pregnancy & Breastfeeding: Avoid due to its estrogen-like activity and lack of adequate safety information during pregnancy.
Source: Synthetic
EWG Rating: N/A
Beta hydroxy acids (BHA)
Use in Moderation, Avoid During Pregnancy
A chemical exfoliant that penetrates deep into pores to dissolve dead skin cells and excess oils. It is widely used in acne treatments due to its anti-inflammatory and antibacterial properties. A common type of BHA is salicylic acid, which can cause skin, eye, and lung irritation.
Commonly Found In: Beauty
Pregnancy & Breastfeeding: Topical salicylic acid (BHA) is generally considered safe for use during pregnancy when applied in low concentrations (≤2%) and used sparingly. Ingesting this is not recommended. It affects prostaglandins, which play important roles in fetal development, blood flow, and the timing of labor. Depending on the dose and timing, aspirin can cross the placenta and interfere with normal processes, potentially increasing risk.
Source: Synthetic
EWG Rating: 1-4 depending on usage and type
Bisabolol
Use in Moderation
A skin-soothing ingredient used for its anti-inflammatory and conditioning properties. It comes in two forms: alpha-bisabolol, typically derived from plants like chamomile, and beta-bisabolol, which is often synthetically produced or derived from corn or cotton, sometimes from GMO sources.
Commonly Found In: Beauty
Pregnancy & Breastfeeding: Generally considered safe for topical use during pregnancy. Some people prefer alpha-bisabolol because it is plant-derived, but no specific pregnancy concerns have been identified for beta-bisabolol at cosmetic use levels.
Source: Natural (alpha form) / Synthetic (beta form, may be GMO)
EWG Rating: 2
Bisphenol A (BPA)
Avoid
A synthetic chemical used in some plastics, food packaging, and can linings. BPA has been widely studied for its hormone-disrupting effects and has been linked to concerns involving reproductive health, metabolic health, cardiovascular disease, and developmental outcomes. Because BPA can mimic estrogen in the body, many individuals choose to limit exposure whenever possible.
Commonly Found In: Food + Beverages
Pregnancy & Breastfeeding: BPA can cross the placenta and interact with hormone receptors, potentially influencing fetal development and the early-life immune, neurological, and reproductive systems. For this reason, many health professionals recommend minimizing BPA exposure during pregnancy and breastfeeding.
Source: Synthetic (from petroleum)
EWG Rating: 7
Bleached White Flour
Avoid
A highly refined flour that has been chemically treated to create a lighter color, softer texture, and longer shelf life. Bleaching agents such as benzoyl peroxide or chlorine may be used during processing, and some products have historically contained potassium bromate, a dough-strengthening additive that has raised concerns regarding carcinogenicity and has been restricted or banned in several countries. The refining process also removes much of the grain's natural fiber, vitamins, minerals, and beneficial plant compounds, resulting in a product that is less nutrient-dense than whole grain alternatives.
Commonly Found In: Food + Beverage (baked goods, breads, pastries, packaged snacks)
Pregnancy & Breastfeeding: Often avoided during pregnancy due to its highly processed nature and the use of chemical bleaching agents, especially when less processed alternatives are available.
Source: Synthetic (chemically treated)
EWG Rating: N/A
Blue 1 (FD&C Blue No. 1, Brilliant Blue FCF, CI 42090)
Avoid
A synthetic dye made from petroleum and used to give foods, drinks, and personal care products a bright blue color. Synthetic food dyes have been linked to hyperactivity and other behavioral effects in some children, especially those who are more sensitive to them. Blue 1 may also contain aniline and cadmium as manufacturing contaminants. Aniline can affect the blood and is toxic at high exposures, while cadmium is a toxic heavy metal that can accumulate in the body and damage the kidneys, bones, and other organs. These contaminants are not necessarily present in every product, which is why manufacturing and purity testing matter.
Commonly Found In: Food + Beverage + Beauty (candy, drinks, frosting, cereals, snacks, medications, supplements, toothpaste, skincare, bath products)
Pregnancy & Breastfeeding: Avoid when possible to reduce unnecessary exposure to synthetic dyes and potential manufacturing contaminants. Blue 1 itself is not considered a known reproductive or developmental toxin.
Source: Synthetic (petroleum-derived)
EWG Rating: 3-7
Boric Acid
Avoid
A compound made from boron, oxygen, and hydrogen, used for its antiseptic and antifungal properties and sometimes as a preservative or pesticide. Research has linked boric acid and other boron compounds to reproductive and hormonal effects, including impacts on testosterone levels and fertility markers (FSH and testosterone levels), particularly with repeated or higher exposures.
Commonly Found In: Beauty + Household + Supplements (Eye drops, vaginal suppositories, antifungal creams, pesticides, and sometimes diaper creams or natural deodorants).
Pregnancy & Breastfeeding: Avoid due to concerns around reproductive and hormonal effects, especially with repeated exposure.
Source: It occurs naturally in some minerals but is usually refined synthetically for consumer products.
EWG Rating: 7
Botulinum Toxin (Botox)
Avoid
A neurotoxin produced by the bacterium Clostridium botulinum and used in cosmetic and medical injections to temporarily block nerve signals to muscles. By interrupting nerve–muscle communication, it reduces muscle movement, which can soften the appearance of wrinkles. Repeated or high-dose use may contribute to localized muscle weakness and changes in skin texture over time.
Commonly Found In: Beauty (injectable cosmetic treatments)
Pregnancy & Breastfeeding: Avoid during pregnancy due to limited safety data and its mechanism of action as a neurotoxin.
Source: Synthetic (from bacteria)
EWG Rating: N/A
Brassicamidopropyl Dimethylamine
Use in Moderation
A conditioning agent that can be derived from plants in the Brassicaceae family (such as rapeseed or broccoli) or produced synthetically. It is often used as an alternative to quaternary ammonium compounds (quats) to improve hair slip and manageability. While generally considered less of a concern than traditional quats, it can still cause irritation for some individuals, particularly those with sensitive skin.
Commonly Found In: Beauty
Pregnancy & Breastfeeding: Generally considered low concern for topical use; those with sensitive skin may wish to patch test.
Source: Natural (plant-based) or Synthetic
EWG Rating: 2-4
Bromelain
Use in Moderation
A digestive enzyme naturally found in pineapple that helps break down protein. It is generally considered low-concern, but larger amounts can cause stomach upset or diarrhea, and it may trigger an allergic reaction in people who are sensitive to pineapple. Powdered forms can also irritate the lungs if inhaled.
Commonly Found In: Food + Beverage + Supplements (digestive supplements, protein blends)
Pregnancy & Breastfeeding: Limited safety data
Source: Natural (from pineapple)
EWG Rating: 1-2
Bronopol
Avoid
A synthetic preservative used to prevent the growth of bacteria and extend the shelf life of personal care products. Bronopol is considered a formaldehyde-releasing preservative, meaning it can slowly break down, releasing small amounts of formaldehyde over time. Formaldehyde has been associated with skin irritation, allergic reactions, respiratory concerns, and carcinogenicity with sufficient exposure.
Commonly Found In: Beauty + Personal Care (lotions, creams, shampoos, liquid soaps)
Pregnancy & Breastfeeding: Best avoided due to formaldehyde-releasing potential
Source: Synthetic
EWG Rating: N/A
Brominated Flame Retardants (BFRs)
Avoid
A group of synthetic chemicals added to furniture, mattresses, electronics, and textiles to reduce flammability. They can migrate from products into dust and have been linked to hormone disruption, neurodevelopmental concerns, and potential long-term health risks.
Commonly Found In: Household (furniture, mattresses, electronics, carpets, textiles)
Pregnancy & Breastfeeding: Best avoided due to potential developmental and endocrine effects
Source: Synthetic
EWG Rating: N/A
Butylated Hydroxy Toluene (BHT)
Avoid
A synthetic antioxidant used to prevent oils and formulas from going rancid. It’s used in some foods/packaging, supplements, and personal care products, and has been linked to liver changes in animal studies, with endocrine-related effects noted in some research.
Commonly Found In: Food + Food Packaging + Supplements + Beauty/Personal Care ( lotions, perfumes, foundations, some snack foods, margarine, cereals)
Pregnancy & Breastfeeding: Best avoided to minimize endocrine-active additives
Source: Synthetic
EWG Rating: N/A
Butane
Avoid
A highly flammable petroleum-derived gas used as an aerosol propellant in spray products. Inhalation exposure can irritate the respiratory system and affect the nervous system, and misuse carries serious health risks.
Commonly Found In: Beauty + Household (dry shampoo, hairspray, deodorant spray, air fresheners, cleaning sprays)
Pregnancy & Breastfeeding: Best avoided due to inhalation exposure concerns
Source: Synthetic (petroleum)
EWG Rating: 3-7
Butyl Acetate
Use in Moderation
A synthetic solvent used to help dissolve ingredients and improve the application of nail products, fragrances, and some cosmetics. While generally considered low-concern for occasional use, exposure may irritate the eyes, skin, and respiratory tract, especially in poorly ventilated spaces or with frequent exposure.
Commonly Found In: Beauty (nail polish, nail polish remover, gel/top coats, base coats, quick-dry sprays, nail primer/dehydrator, fragrances)
Pregnancy & Breastfeeding: Best avoided in high concentrations (like nail salons) due to inhalation exposure concerns
Source: Synthetic
EWG Rating: 1
Butyloctyl Salicylate
Use In Moderation
A synthetic ingredient used in sunscreens and cosmetics to improve texture and spreadability, help dissolve other ingredients, and sometimes boost SPF. It is made from salicylic acid, and the body may break some of it back down into salicylic acid. Reproductive and developmental effects have been found with high exposure to some salicylates, but these findings don't show that normal cosmetic use of Butyloctyl Salicylate causes the same effects.
Commonly Found In: Beauty (sunscreens, tinted mineral sunscreens, SPF moisturizers, primers, foundations, lip products with SPF)
Pregnancy & Breastfeeding: Because reproductive and developmental research specifically on Butyloctyl Salicylate is still being evaluated, some may choose to limit repeated use during pregnancy
Source: Synthetic
EWG Rating: 1-4
Butylparaben
Avoid
A preservative used to help prevent mold, yeast, and bacteria from growing in products. Butylparaben can act like estrogen in the body. In lab studies using human breast cells, it activated estrogen receptors and caused estrogen-sensitive breast cancer cells to grow.
Commonly Found In: Beauty + Personal Care (lotions, soaps, makeup, deodorant, shampoos, conditioners), some medications and personal care products
Pregnancy & Breastfeeding: Avoid when possible because of its estrogen-like activity and potential hormone effects.
Source: Synthetic
EWG Rating: 9
Butylphenyl Methylpropional
Avoid
A synthetic fragrance ingredient used to create floral, fresh, or lily-like scents in personal care and household products. It has been banned in the European Union due to concerns regarding reproductive toxicity. It is also associated with skin sensitization and allergic reactions in some individuals. Because fragrance ingredients often provide scent rather than product performance, many people choose to avoid them when safer alternatives are available.
Commonly Found In: Household + Beauty/Personal Care (laundry detergent, air fresheners, candles, perfumes, lotions, soaps, cleaning products)
Pregnancy & Breastfeeding: Best avoided due to reproductive toxicity concerns
Source: Synthetic
EWG Rating: 1
C
C8 Alcohol
Use in Moderation
A fatty alcohol used as a solvent, emollient, or texture-enhancing ingredient in personal care and household products. Fatty alcohols are different from drying alcohols and are generally considered lower concern, though some individuals with sensitive skin may experience irritation depending on the formulation.
Commonly Found In: Beauty, Household
Pregnancy & Breastfeeding: Generally considered safe in topical products, but use with caution if skin sensitivity occurs.
Source: Synthetic
EWG Rating: N/A
C10–16 Pareth
Avoid
A cleansing ingredient used to help remove grease and oil. The concern is how it is made. Pareths are ethoxylated, which means they can be contaminated with ethylene oxide and 1,4-dioxane if they aren't properly purified. Both are linked to cancer, and because they are leftover contaminants from manufacturing, you won't normally see them listed on the ingredient label.
Commonly Found In: Household + Beauty (dish soaps, cleaners, shampoos, cleansers)
Pregnancy & Breastfeeding: Avoid to reduce unnecessary exposure to possible manufacturing contaminants.
Source: Synthetic/processed (ethoxylated)
EWG Rating: 1
C12–14 Alcohols Ethoxylated Propoxylated
Avoid
A cleansing ingredient used to help break up grease and dirt. It goes through ethoxylation during manufacturing, which can leave behind 1,4-dioxane, a contaminant linked to cancer. It can also cause serious eye irritation and is very toxic to aquatic life.
Commonly Found In: Household (dish detergents, floor cleaners)
Pregnancy & Breastfeeding: Avoid due to contamination concerns.
Source: Synthetic (ethoxylated, petroleum-derived)
EWG Rating: 2-3
C12–15 Pareth-3
Avoid
A cleansing ingredient that helps water mix with oils and remove dirt and grease. It is made via ethoxylation, which can leave behind ethylene oxide and 1,4-dioxane if not properly purified. Both are linked to cancer, making the possible contamination the bigger concern with this ingredient. EWG specifically lists both as contamination concerns for C12–15 Pareth-3.
Commonly Found In: Beauty + Household (hair color, conditioners, shampoos, stain removers, laundry products)
Pregnancy & Breastfeeding: Avoid to reduce unnecessary exposure to possible manufacturing contaminants.
Source: Synthetic/processed (ethoxylated)
EWG Rating: 1–2
C15–19 Alkane
Use in Moderation
A lightweight ingredient used to help beauty products spread smoothly and feel less greasy. It can be made from plant-based or petroleum sources and is generally considered lower concern. With petroleum-derived versions, how well the ingredient is refined matters because some petroleum starting materials can contain PAHs, a group of chemicals that includes known carcinogens. Proper refining greatly reduces this concern. You can't tell from the ingredient label how it was refined, so look for plant-derived versions or brands that provide information about their sourcing, refining, and purity testing.
Commonly Found In: Beauty + Personal Care (sunscreens, foundations, primers, moisturizers, hair products)
Pregnancy & Breastfeeding: No specific concerns have been identified with normal cosmetic use
Source: Plant-derived or petroleum-derived (processed)
EWG Rating: 1–3
C9–11 Pareth-8
Avoid
An ethoxylated (PEG-type) surfactant used to break up grease and help formulas rinse clean. It can be irritating, particularly to the eyes and sensitive skin. Because it is manufactured via ethoxylation, contamination with 1,4-dioxane and ethylene oxide may occur if manufacturing and purification processes are not carefully controlled. Some formulations may also raise environmental concerns due to aquatic toxicity.
Commonly Found In: Household (dish soaps, degreasers, surface cleaners, laundry products)
Pregnancy & Breastfeeding: Avoid to reduce unnecessary exposure to possible manufacturing contaminants
Source: Synthetic (ethoxylated; typically petroleum-derived)
EWG Rating: 1-2
Cadmium
Avoid
A heavy metal that can build up in the body over time (especially in the kidneys) and is classified as a human carcinogen. Long-term exposure is the biggest concern.
Commonly Found In: Household (contaminated dust, some older pigments/paint, certain imported items, some contaminated soil brought indoors, electronics)
Pregnancy & Breastfeeding: Avoid due to carcinogenic and developmental risks
Source: Natural (hazardous heavy metal)
EWG Rating: N/A
Calcium Alginate
Use in Moderation
A thickener and stabilizer made from brown seaweed. Seaweed can pick up contaminants from the water it grows in, so where it comes from and how it is tested matters. Calcium alginate can contain small amounts of heavy metals like lead and arsenic, which can build up in the body with enough exposure over time. You can't tell from the ingredient label how well it was tested, so look for food-grade calcium alginate from companies that test their ingredients for heavy metals, especially in products you use regularly.
Commonly Found In: Food + Beverage (gels, bakery products, sauces, processed foods, dairy alternatives, thickened drinks)
Pregnancy & Breastfeeding: Use in moderation and look for better-sourced or tested products when possible.
Source: Natural (from brown seaweed, then processed)
EWG Rating: 1
Calcium Aluminum Borosilicate
Use in Moderation
A glass-based ingredient used to give makeup shimmer, sparkle, and a smoother feel. The ingredient itself is considered a lower concern, but purity matters. Testing has found lead in some Calcium Aluminum Borosilicate, so look for brands that test their finished products or raw ingredients for heavy metals, especially with makeup you use regularly. You can't tell how well it was tested just by looking at the ingredient label.
Commonly Found In: Beauty (eyeshadow, highlighters, shimmer blush, glittery lip products)
Pregnancy & Breastfeeding: Generally considered low concern in typical topical use; use caution with loose powders to reduce inhalation exposure
Source: Synthetic
EWG Rating: 2
Calcium Lactate
Use in Moderation
A calcium salt used to add calcium, control acidity, and improve texture in foods, drinks, and supplements. Calcium Lactate itself is considered lower concern, but purity matters. Lead, arsenic, mercury, and fluoride are recognized impurities that manufacturers have to control. You can't tell from the ingredient label how well it was tested, so look for supplements and products from companies that test for heavy metals and provide information about their quality or purity testing, especially with products you use regularly.
Commonly Found In: Food + Beverage + Supplements (fortified drinks, dairy alternatives, canned foods, baked goods, calcium supplements)
Pregnancy & Breastfeeding: Generally considered lower concern in normal food amounts. With supplements or products used regularly, look for brands that test for heavy metals
Source: Processed (manufactured calcium salt; often made from fermentation-derived lactic acid)
EWG Rating: 2-5
Calcium Phosphate
Use in Moderation
A calcium and phosphorus compound used to prevent clumping, improve texture, help foods rise, or add calcium. Calcium Phosphate itself is considered lower concern, but it adds to your total phosphorus intake. Getting too much phosphorus, especially from several processed foods, fortified products, or supplements, can put extra stress on the kidneys. Purity also matters because heavy metals like lead, arsenic, cadmium, and mercury are recognized impurities that manufacturers have to control. You can't tell this from the ingredient label, so look for supplements and regularly used products from companies that test for heavy metals and other contaminants.
Commonly Found In: Food + Beverage + Supplements (baking mixes, processed cheese, powdered drinks, fortified foods, dairy alternatives, calcium supplements)
Pregnancy & Breastfeeding: Generally considered lower concern in normal food amounts. Be mindful of total phosphorus and calcium intake from fortified foods and supplements
Source: Processed mineral compound
EWG Rating: 1
Calcium Sodium Borosilicate
Use in Moderation
A glass-based ingredient used to add shimmer, sparkle, and a smoother feel to makeup. The ingredient itself is considered lower concern, but purity matters because lead, arsenic, and mercury are recognized impurities that manufacturers have to control. You can't tell from the ingredient label how well it was tested, so look for brands that test their finished products or raw ingredients for heavy metals, especially with makeup you use regularly.
Commonly Found In: Beauty (eyeshadow, highlighter, blush, lipstick, lip gloss, foundation and other shimmer cosmetics)
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concern has been identified from the ingredient itself. Choosing products tested for heavy metals can help reduce unnecessary exposure
Source: Synthetic (borosilicate glass)
EWG Rating: 2
Camphor
Avoid
A natural or synthetic ingredient used for its cooling feeling, scent, and temporary pain relief. Camphor can be toxic if swallowed or if too much gets into the body. It can affect the brain and nervous system and cause nausea, confusion, seizures, and, in severe cases, breathing problems. Children are especially vulnerable, and even relatively small amounts can cause serious poisoning.
Commonly Found In: Household + Beauty + Medical (chest rubs, muscle rubs, pain-relief creams, balms, ointments, and some fragranced products)
Pregnancy & Breastfeeding: Avoid unnecessary use during pregnancy because camphor can cross the placenta and there isn't enough good safety data to know what amount is safe.
Source: Natural (from camphor trees) or synthetically made
EWG Rating: 3–4
Canola Oil (Low-Erucic Acid Rapeseed Oil)
Use In Moderation
A vegetable oil made from specially bred varieties of rapeseed that contain very low amounts of erucic acid. Most conventional canola oil is highly refined, and solvent extraction using hexane may be part of the manufacturing process. Small solvent residues can remain after processing, although most of the solvent is removed during refining. Like other unsaturated oils, canola oil can also break down and form oxidation products when repeatedly heated or used for high-temperature frying. If you want a less processed option, look for organic, expeller-pressed or cold-pressed canola oil.
Commonly Found In: Food + Beverage (processed snacks, baked goods, salad dressings, mayonnaise, restaurant foods, cooking oils and margarines)
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concern has been established from normal dietary use.
Source: Plant-derived; conventional versions are commonly refined and may be solvent-extracted
EWG Rating: 1
Caprylohydroxamic Acid
Use in Moderation
A preservative helper used to keep bacteria, yeast, and mold from growing in beauty and personal care products. Caprylohydroxamic acid itself is generally considered a lower concern, but skin sensitivity is the bigger issue. Research has found allergic skin reactions in some people, with damaged or irritated skin potentially allowing more of the ingredient to penetrate. Because it can show up in several products used regularly, people with eczema, sensitive skin, or a damaged skin barrier may want to pay closer attention to it.
Commonly Found In: Beauty + Personal Care (moisturizers, serums, cleansers, shampoo, body wash, sunscreen, makeup, baby products, and haircare)
Pregnancy & Breastfeeding: Generally considered lower concern at the amounts used in cosmetics. Current evidence does not show a meaningful reproductive or developmental concern at normal cosmetic exposure.
Source: Synthetic
EWG Rating: 1
Caramel Color
Avoid
A coloring ingredient made by heating sugars and processing them to create a brown color used in foods and beverages. Certain manufacturing methods may produce 4-methylimidazole (4-MEI), a byproduct that has raised concerns regarding carcinogenicity. Caramel color is used primarily to enhance or standardize appearance and does not provide any nutritional benefit.
Commonly Found In: Food + Beverage (soda, root beer, flavored coffee creamers, barbecue sauce, soy sauce, breakfast cereals, granola bars, sports drinks, candy, some plant-based milks)
Pregnancy & Breastfeeding: Avoid due to contamination concerns
Source: Synthetic
EWG Rating: 1
Carbamide Peroxide
Use In Moderation
A whitening ingredient that breaks down into hydrogen peroxide and urea to help remove stains from teeth. It can cause temporary tooth sensitivity, gum irritation, or mouth irritation, especially with stronger products or frequent use.
Commonly Found In: Oral Care (whitening gels, strips, trays, pens and some whitening rinses)
Pregnancy & Breastfeeding: Avoid elective teeth whitening during pregnancy because pregnancy-specific safety data is limited
Source: Synthetic
EWG Rating: 2
Carmine (Cochineal)
Use in Moderation
A red or pink dye made from cochineal insects and used to color foods and beauty products. It is generally considered low concern, but it can cause allergic reactions in some people, including hives, swelling, breathing problems, and rarely a serious allergic reaction. Carmine has caused enough allergic reactions that it has to be listed by name on food and cosmetic labels.
Commonly Found In: Food + Beverage + Beauty (yogurt, candy, drinks, lipstick, blush, eyeshadow, capsules and tablets)
Pregnancy & Breastfeeding: Generally considered low concern unless you are allergic or sensitive to it.
Source: Natural (made from cochineal insects)
EWG Rating: 1
Carob Bean (Locust Bean Gum)
Use in Moderation
A natural gum made from carob tree seeds and used to thicken and improve the texture of foods. It is generally considered lower concern, but larger amounts may cause bloating, gas, diarrhea, or other digestive discomfort because it is fermented by gut bacteria. Rare allergic reactions have also been reported. Purity matters, especially in products for children, because specifications for locust bean gum include limits on toxic elements such as lead, mercury, and arsenic, and the gum can also be vulnerable to microbial or mold contamination if it is not properly processed and tested.
Commonly Found In: Food + Beverage (ice cream, dairy alternatives, yogurt, sauces, gluten-free baking, protein drinks)
Pregnancy & Breastfeeding: Generally considered safe, but purity matters
Source: Natural
EWG Rating: 1
Carrageenan
Avoid
A thickener and stabilizer made from red seaweed and commonly added to processed foods to make them thicker and creamier. Carrageenan is poorly absorbed by the body, but the bigger concern is what it may do inside the gut. Research suggests it may irritate the intestinal lining, alter gut bacteria, and trigger or worsen inflammation, especially in people with sensitive or inflamed digestive systems. Animal studies have also found GI inflammation and immune effects at higher exposures. The research is still debated, but because carrageenan provides no nutritional benefit and alternatives are widely available, it does not meet a stricter low-tox standard.
Commonly Found In: Food + Beverage + Supplements + Beauty (dairy alternatives, deli meats, coffee creamers, protein shakes, gummies, toothpaste, lotions)
Pregnancy & Breastfeeding: Use with caution; often avoided by those minimizing gut irritants
Source: Natural (from seaweed)
EWG Rating: 1
Cellulase
Use in Moderation
An enzyme that breaks down cellulose and is commonly made through fermentation using fungi or bacteria. Cellulase is generally considered lower concern when eaten, but inhaling powdered forms can trigger respiratory allergies or asthma-like reactions, especially with repeated exposure. Some cellulase is made using fungal strains such as Aspergillus or Trichoderma, including genetically modified strains. The production organism is removed during manufacturing, although small amounts of proteins from the fermentation process may remain, making sourcing and purification worth considering for sensitive individuals.
Commonly Found In: Food + Beverage (processed foods, baked goods, juices, fermented products)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified. Use caution with powdered forms that could be inhaled.
Source: Can be natural (bacterial- or mold-derived through fermentation)
EWG Rating: N/A
Cellulose Gum
Use in Moderation
A thickener and stabilizer made by chemically modifying plant cellulose, usually from wood pulp or cotton. It is generally considered to be of lower concern, but research suggests it may affect the gut microbiome and intestinal environment. In a small human study, higher daily intake changed gut bacteria, reduced microbial diversity, altered beneficial gut metabolites, and caused slightly more abdominal discomfort. Animal studies have also raised concerns around gut inflammation.
Commonly Found In: Food + Beverage (ice cream, dairy alternatives, sauces, dressings, gluten-free baked goods)
Pregnancy & Breastfeeding: Generally considered safe in typical food amounts
Source: Plant-derived (processed cellulose)
EWG Rating: 1
Ceresin
Avoid
A mineral-based hydrocarbon wax used to thicken products, add structure, and sometimes replace beeswax. Ceresin itself is considered lower concern, but how it is sourced and refined is the bigger issue. Mineral and petroleum-derived waxes can contain PAHs (polycyclic aromatic hydrocarbons) if they are not properly refined, and some PAHs are known or suspected carcinogens. EWG requires ceresin used in EWG VERIFIED products to be highly refined, made from noncarcinogenic source material, and meet strict limits for PAH contamination. Ceresin also has concerns around persistence and buildup in the body.
Commonly Found In: Beauty (lip balms, creams, ointments, makeup, hair products)
Pregnancy & Breastfeeding: Avoid when possible to reduce unnecessary exposure to mineral-derived hydrocarbons and potential contaminants such as PAHs. Properly refined ceresin itself is not considered a known reproductive or developmental toxin.
Source: Mineral-derived (petroleum/coal)
EWG Rating: 1
Cetalkonium
Avoid
A synthetic quaternary ammonium compound, or quat, used to kill germs, preserve products, and help ingredients mix together. It can irritate the skin and eyes, and inhalation is a bigger concern because Cetalkonium Chloride has been identified as an asthma-triggering sensitizer. There are also growing reproductive and developmental concerns around quats as a group, although these effects have not been clearly established for Cetalkonium Chloride itself. It is also very toxic to aquatic life and can have long-lasting environmental effects.
Commonly Found In: Household + Industrial (disinfectants, specialty cleaners, some industrial or professional-use formulations)
Pregnancy & Breastfeeding: Avoid when possible, especially in sprays or products that can be inhaled. Some animal studies have found reproductive concerns with certain quats, although pregnancy-specific research on cetalkonium chloride is limited.
Source: Synthetic
EWG Rating: N/A
Ceteareth-25
Avoid
A synthetic ingredient used to help oil and water mix together and improve the texture of beauty products. Ceteareth-25 is made through ethoxylation, which can leave behind ethylene oxide and 1,4-dioxane if the ingredient is not properly purified. Both are concerning manufacturing contaminants because of their links to cancer. EWG also flags Ceteareth-25 as a penetration enhancer, meaning it may help other ingredients penetrate the skin more easily. The amount of contamination depends on how well the ingredient is manufactured, purified, and tested.
Commonly Found In: Beauty + Household (creams, lotions, sunscreens, hair conditioners, cleansers, some cleaning products)
Pregnancy & Breastfeeding: Avoid when possible to reduce unnecessary exposure to ethoxylated ingredients and potential manufacturing contaminants such as ethylene oxide and 1,4-dioxane.
Source: Synthetic (ethoxylated)
EWG Rating: 1
Cetrimonium Chloride
Avoid
A quaternary ammonium compound used as a conditioning and antistatic agent in hair and personal care products. It is associated with skin and eye irritation, and inhalation exposure can be a concern in spray products.
Commonly Found In: Beauty (conditioners, detanglers, leave-in sprays, styling creams, hair masks)
Pregnancy & Breastfeeding: Often avoided due to irritation and inhalation exposure concerns
Source: Synthetic
EWG Rating: 2
Chlorhexidine Diacetate
Avoid
A synthetic antiseptic/disinfectant used to reduce bacteria. It can cause mild skin irritation and sensitivity, and allergic reactions have been reported in some individuals. This is also very toxic to aquatic life.
Commonly Found In: Household + Medical/Dental (antiseptic washes, mouth rinses, skin cleansers, wound care products, disinfecting solutions)
Pregnancy & Breastfeeding: Use with caution if sensitive
Source: Synthetic
EWG Rating: N/A
Chlorhexidine Digluconate
Avoid
A synthetic antibacterial ingredient used to kill germs in personal care, dental, and medical products. It can irritate the skin and eyes and cause allergic reactions, which can be serious in people who are sensitive to it. Frequent use may also disrupt the good bacteria in your mouth and may contribute to bacteria becoming resistant to it over time. It is also very toxic to aquatic life.
Commonly Found In: Beauty + Personal Care (acne or antibacterial washes, mouth rinses, some cleansers), Medical/Dental products
Pregnancy & Breastfeeding: Avoid unnecessary everyday use. Medical or dental use may still be needed when recommended by your healthcare provider
Source: Synthetic
EWG Rating: 1
Chlorine
Avoid
This poisonous disinfectant and bleaching agent is used in household cleaning and water treatment, as well as manufacturing PVC. Exposure can irritate the skin, eyes, and respiratory tract, especially in poorly ventilated areas or at higher concentrations.
Commonly Found In: Household (bleach cleaners, disinfecting products, pool chemicals, chlorinated water exposure)
Pregnancy & Breastfeeding: Avoid due to irritation and toxic inhalation exposure concerns
Source: Synthetic
EWG Rating: N/A
Chlorine Dioxide
Avoid
A synthetic oxidizing gas used as a bleaching agent in some paper processing and as a disinfectant in certain water treatment applications. Exposure can irritate the eyes, skin, and respiratory tract, especially if inhaled. Inhaling too much can cause bronchitis and asthma- like symptoms.
Commonly Found In: Household (some disinfecting products, water treatment applications, “chlorine-free” paper processing context)
Pregnancy & Breastfeeding: Limited pregnancy-specific data; use with caution to minimize inhalation exposure
Source: Synthetic
EWG Rating: N/A
Chloroform
Avoid
A chemical that can form as a by-product of water disinfection when chlorine reacts with organic matter. Higher exposures can affect the nervous system, liver, and kidneys.
Commonly Found In: Household (chlorinated tap water, hot showers/steam exposure, pools, some water disinfection contexts)
Pregnancy & Breastfeeding: Avoid or minimize exposure due to organ toxicity concerns
Source: Synthetic (disinfection by-product)
EWG Rating: N/A
Chloromethane (Methyl Chloride)
Avoid
A volatile synthetic gas used primarily as an industrial chemical. High exposure can affect the nervous system and cause symptoms such as headache, dizziness, and nausea.
Commonly Found In: Household (rare in typical household products; more associated with industrial use and chemical manufacturing)
Pregnancy & Breastfeeding: Avoid due to neurotoxicity risk with inhalation exposure
Source: Synthetic
EWG Rating: N/A
Chlorphenesin
Avoid
A synthetic preservative used to limit microbial growth in personal care products. It can irritate the skin and may be problematic for individuals with sensitivities. In vitro research has shown cellular toxicity in ocular cells, raising concern for products used near the eye.
Commonly Found In: Beauty (lotions, creams, serums, makeup, deodorants, hair products)
Pregnancy & Breastfeeding: Limited pregnancy-specific data; often avoided out of caution
Source: Synthetic
EWG Rating: 4
Chromium Oxide Green
Avoid
A mineral-based green pigment used in cosmetics. Concerns relate to possible contamination with trace heavy metals (such as lead, cadmium, or other chromium impurities) depending on sourcing and manufacturing, as well as hazard-based assessments that flag potential developmental and reproductive toxicity.
Commonly Found In: Beauty (eyeshadow, eyeliner, brow products, face paint, makeup pigments)
Pregnancy & Breastfeeding: Avoid due to heavy metal contamination concerns
Source: Mineral-derived (inorganic pigment
Chromium-6 (Hexavalent Chromium)
Avoid
A highly toxic form of chromium known to be carcinogenic. Exposure is associated with increased cancer risk and can damage cells and tissues.
Commonly Found In: Household (contaminated drinking water, pollution-related exposure, some industrial residues)
Pregnancy & Breastfeeding: Avoid due to carcinogenic and toxic exposure concerns
Source: Naturally occurring and industrially produced
EWG Rating: N/A
CI 42090 (Blue Lake No. 4)
Avoid
A synthetic blue colorant used in cosmetics (an aluminum “lake” form of Blue 1). EWG flags high concern for contamination, which can include trace contaminants such as heavy metals (for example lead, arsenic, cadmium, or mercury) depending on manufacturing controls, along with use restrictions and developmental/reproductive toxicity concerns.
Commonly Found In: Beauty (makeup, skincare, hair products)
Pregnancy & Breastfeeding: Often avoided to minimize exposure to synthetic dyes and potential trace contaminants
Source: Synthetic
EWG Rating: 3-8
CI 77007 (Ultramarines)
Use in Moderation
A mineral-derived inorganic pigment used to provide blue or violet color in cosmetics. While generally considered lower concern than synthetic dyes, it may contain trace heavy metals such as lead or chromium depending on raw material sourcing and purification standards.
Commonly Found In: Beauty (eyeshadow, eyeliner, mascara, face powders)
Pregnancy & Breastfeeding: Generally considered low concern when cosmetic-grade and impurity-controlled
Source: Natural (mineral-derived)
EWG Rating: 2
Citral
Use in Moderation
A naturally occurring scent ingredient found in essential oils like lemongrass and citrus oils. It can irritate the skin and cause allergic reactions in some people, especially with repeated exposure or if you already have sensitive skin or fragrance allergies.
Commonly Found In: Beauty + Household (skincare, shampoo, conditioner, perfume, deodorant, soaps, cleaners, and air fresheners)
Pregnancy & Breastfeeding: Generally low concern in small amounts, but limit if it causes skin irritation or sensitivity.
Source: Natural or synthetic (naturally found in many essential oils but can also be made synthetically)
EWG Rating: 2-4
Citric Acid (Synthetic)
Use in Moderation
Citric acid occurs naturally in citrus fruits, but most of the citric acid used in packaged foods, supplements, beauty products, and cleaners is manufactured through fermentation, commonly using Aspergillus niger, a type of mold, to ferment sugars. The finished ingredient is purified and is not the same as consuming mold. Citric acid itself is generally considered low concern, although concentrated forms can irritate the skin, eyes, or lungs, especially in powders and sprays.
Commonly Found In: Food + Beverage + Supplements + Beauty + Household (soft drinks, candy, packaged foods, supplements, skincare, bath products, detergents, cleaning products)
Pregnancy & Breastfeeding: Generally considered low concern in typical amounts. Avoid inhaling concentrated powders or sprays.
Source: Natural or manufactured through fermentation
EWG Rating: 1-2
Citrus Limon (Lemon) Peel Oil
Use in Moderation
An essential oil made from lemon peels and commonly used for fragrance. It can irritate the skin or trigger an allergic reaction, especially in sensitive individuals. Some lemon peel oils can also be phototoxic, meaning they can make exposed skin more sensitive to sunlight and increase the chance of redness or burns.
Commonly Found In: Beauty + Household (skincare, cleansers, creams, hair products, perfumes, soaps, cleaners, essential oil blends)
Pregnancy & Breastfeeding: Use in moderation, especially with leave-on products that will be exposed to sunlight.
Source: Natural (lemon peel-derived)
EWG Rating: 4-6
Cocamide DEA
Avoid
A foaming and thickening ingredient made from coconut fatty acids and DEA. The biggest concern is its possible link to cancer. It can also contain leftover DEA and can form nitrosamines, some of which are known or suspected carcinogens, depending on how the product is made and what other ingredients are used with it.
Commonly Found In: Beauty (shampoos, body washes, cleansers, bubble baths)
Pregnancy & Breastfeeding: Avoid due to DEA/nitrosamine-related concerns
Source: Synthetic
EWG Rating: 8
Cocamide MEA
Avoid
A foaming and thickening ingredient usually made from coconut fatty acids and MEA. The bigger concern is how it is made and what can be left behind. Cocamide MEA can be contaminated with nitrosamines, some of which are linked to cancer, if it is not properly made and purified. It can also irritate the skin and eyes.
Commonly Found In: Beauty (shampoos, body washes, facial cleansers, liquid hand soaps, shaving creams)
Pregnancy & Breastfeeding: Avoid when possible due to potential nitrosamine contamination rather than a proven pregnancy-specific risk.
Source: Synthetic
EWG Rating: 4
Cocamidopropyl Betaine
Use in Moderation
A cleansing and foaming ingredient commonly made using coconut-derived fatty acids. It is generally considered low concern, but it can irritate the skin or cause allergic reactions in some people. The bigger concern is what can be left behind when it is made, including DMAPA and amidoamine, which are linked to many of the allergic reactions seen with this ingredient. How well it is made and purified matters.
Commonly Found In: Beauty + Household (shampoos, body washes, facial cleansers, baby wash, liquid hand soap, household cleaners)
Pregnancy & Breastfeeding: Generally considered low concern, but limit if you have sensitive or easily irritated skin
Source: Synthetic (often made from coconut-derived fatty acids)
EWG Rating: 1-5
Cocamidopropyl Hydroxysultaine
Use in Moderation
A cleansing and foaming ingredient often made using coconut-derived fatty acids. The ingredient itself is generally considered a lower concern, but manufacturing and formulation matter. Small amounts of impurities such as DMAPA can remain from manufacturing, which may contribute to skin irritation or allergic reactions in sensitive people, although well-manufactured ingredients can contain very low levels. There is also potential for nitrosamines to form under certain formulation conditions, which is why manufacturers are advised to control impurities and avoid conditions where nitrosamines can form.
Commonly Found In: Beauty + Household (shampoo, body wash, facial cleansers, hand soap, baby wash, bubble bath, and cleaning products)
Pregnancy & Breastfeeding: Generally considered lower concern when properly manufactured and formulated, but purity matters and repeated exposure through several products may be worth limiting.
Source: Synthetic (often made using coconut-derived fatty acids)
EWG Rating: 1
Colloidal Silver
Use in Moderation
Tiny silver particles suspended in liquid and used for their antibacterial properties. The biggest concern is taking it by mouth regularly. Silver can build up in the body over time and cause argyria, a permanent blue-gray discoloration of the skin. There is also some concern with kidney, liver, and nervous-system effects, and it can interfere with certain medications.
Commonly Found In: Supplements + Oral Care + Beauty (oral drops and sprays, mouthwash, toothpaste, creams, sprays, soaps)
Pregnancy & Breastfeeding: Avoid taking by mouth unless recommended by your healthcare provider.
Source: Mineral-derived (silver)
EWG Rating: 1
Colophonium
Use in Moderation
A sticky resin that comes from pine trees and is used in cosmetics, adhesives, waxes, and other products. It is a known skin allergen, and some of the compounds in the resin can become even more irritating as they are exposed to air and oxidize. Repeated exposure can cause an itchy rash or other skin reactions in people who become sensitive to it.
Commonly Found In: Beauty + Household (mascara, lipstick, eyeliner, hair-removal wax, adhesives, bandages, tapes, glues)
Pregnancy & Breastfeeding: Generally low concern, but avoid if you are allergic or have very sensitive skin.
Source: Natural (pine tree resin)
EWG Rating: 2
Commiphora Myrrha Gum Oil
Use in Moderation
An oil made from myrrh tree resin and used for its scent and in skin and oral care products. It can irritate sensitive skin, especially in stronger amounts. Taking myrrh by mouth is a bigger concern during pregnancy because it may stimulate the uterus.
Commonly Found In: Beauty + Oral Care (facial oils, serums, balms, perfumes, toothpaste, mouthwash, essential oil blends)
Pregnancy & Breastfeeding: Avoid during pregnancy, especially oral or concentrated use, because myrrh may stimulate the uterus and potentially trigger contractions
Source: Natural (myrrh tree resin)
EWG Rating: 1
Copaiba Balsam Oil
Use in Moderation
An oil made from copaiba tree resin, used in skincare and essential oil products. It is generally considered low concern, but it can cause an allergic skin reaction in some people, especially as some of its natural scent compounds oxidize over time.
Commonly Found In: Beauty (serums, facial oils, balms, essential oil blends, skincare products)
Pregnancy & Breastfeeding: Use in moderation. There is not enough research on regular use during pregnancy.
Source: Natural (copaiba tree resin)
EWG Rating: 4
Corn Maltodextrin
Use in Moderation
A highly processed carbohydrate made from corn and added to foods as a thickener, filler, or to improve texture. It is broken down into glucose very quickly and can raise blood sugar fast, especially when you are getting it often in processed foods. It can also be made from GMO corn, so look for organic or non-GMO if that is something you want to avoid.
Commonly Found In: Food + Beverage (protein powders, packaged snacks, sauces, seasonings, drink mixes, supplements, processed foods)
Pregnancy & Breastfeeding: Generally considered low concern, but use in moderation, especially if you are watching blood sugar.
Source: Plant-derived (highly processed, usually from corn)
EWG Rating: 1
Corn Oil
Use in Moderation
A highly refined oil made from corn and commonly used in fried and processed foods. It is very high in omega-6 fats, so getting a good balance of omega-3 fats in your diet matters too. Corn oil can also oxidize when heated for long periods, such as with repeated deep frying. It is commonly made from GMO corn, so look for organic or non-GMO.
Commonly Found In: Food + Beverage (fried foods, chips, processed snacks, dressings, margarine, baked goods, restaurant foods)
Pregnancy & Breastfeeding: Generally considered low concern in normal food amounts. Limit heavily fried and highly processed foods when possible.
Source: Plant-derived (highly refined from corn, which may be GMO)
EWG Rating: 1
Corn Starch
Use in Moderation
A refined starch made from corn and used to thicken foods or add bulk to supplements and medications. Also called cornstarch or maize starch, it is mostly carbohydrate and can raise blood sugar depending on the amount eaten and what else is in the food. Corn can also be affected by mycotoxins, some of which can carry over into the starch during processing. When possible, look for USDA Organic corn starch, especially if it is something consumed regularly.
Commonly Found In: Food + Beverage, Supplements (soups, sauces, baking mixes, capsules/powders)
Pregnancy & Breastfeeding: Generally considered safe in moderation.
Source: Natural (processed from corn, often GMO)
EWG Rating: 1
Coumarin
Use in Moderation
A naturally occurring compound found in plants such as cassia cinnamon and tonka beans that is also used for its sweet scent in fragrance products. Higher amounts of coumarin can damage the liver, which is the main concern with frequent dietary exposure. Coumarin is also a known fragrance allergen and can cause allergic skin reactions in sensitive people. Coumarin itself is prohibited from being directly added to food in the U.S., although it can naturally occur in foods such as cinnamon.
Commonly Found In: Food + Beauty + Household (cassia cinnamon, cinnamon-containing foods, perfumes, lotions, soaps, fragranced products)
Pregnancy & Breastfeeding: Use in moderation, particularly from concentrated or frequent dietary sources.
Source: Natural or synthetic
EWG Rating: 4
Cultured Celery Powder
Avoid
A celery-based ingredient used as a natural source of nitrite to cure and preserve processed meats. It is commonly used in products labeled “uncured” or “no nitrates or nitrites added,” but these products can still contain nitrites from celery. Once formed, celery-derived nitrite can take part in the same reactions as added sodium nitrite, including the formation of nitrosamines under certain processing and cooking conditions, some of which are carcinogenic.
Commonly Found In: Food + Beverage (Bacon, Deli Meats, Hot Dogs, Sausages, Ham, Pepperoni & Other “Uncured” Meats)
Pregnancy & Breastfeeding: Limiting processed meats made with added or naturally derived nitrites may help reduce overall nitrite and potential nitrosamine exposure
Source: Plant-derived (cultured/processed celery)
EWG Rating: N/A
Cyclomethicone
Avoid
A synthetic silicone made from a mixture of cyclic siloxanes, which can include D4, D5 and D6. It is commonly used to give skincare, makeup and hair products a smooth, silky feel and help them spread easily. The biggest concerns are reproductive toxicity with D4 and the environmental persistence of these cyclic silicones. D4 is classified in the EU as suspected of damaging fertility, while D4, D5 and D6 have also been restricted because they can persist and build up in the environment.
Commonly Found In: Beauty + Personal Care (Primers, Foundations, Hair Serums, Deodorants, Skincare & Hair Products)
Pregnancy & Breastfeeding: Consider avoiding because cyclomethicone can include D4, which is classified for reproductive toxicity; typical cosmetic use of cyclomethicone itself has not been shown to cause reproductive harm in humans
Source: Synthetic, silicone-based
EWG Rating: 6
Cyclopentasiloxane (D5)
Avoid
A silicone used to make skincare, makeup, and hair products feel silky and spread easily. Animal studies have found that D5 can affect reproductive hormones, including increasing estrogen and lowering progesterone, along with changes in how the ovaries function. D5 can also contain small amounts of D4, another silicone with reproductive toxicity concerns. Breathing it in is an added concern in sprays and aerosols.
Commonly Found In: Beauty (primers, foundations, hair serums, deodorants, skincare, hair products, sprays)
Pregnancy & Breastfeeding: Avoid when possible due to reproductive hormone concerns found in animal studies and possible D4 contamination. Avoid sprays and aerosols that can be inhaled
Source: Synthetic (silicone-based)
EWG Rating: 6
Cyfluthrin
Avoid
A synthetic insecticide in the pyrethroid family that works by disrupting normal nerve signals. A related form called beta-cyfluthrin may also appear on pesticide labels. The nervous system is the main concern, with animal studies finding effects including changes in movement, tremors, seizures and nerve damage at certain exposures. Breathing it in is an added concern, especially with sprays, foggers and indoor pest treatments. Animal studies during pregnancy have also found lower fetal weights, smaller offspring and skeletal changes with inhalation exposure.
Commonly Found In: Household + Outdoor Products (Insecticides, Bug Sprays, Foggers, Lawn Treatments & Pest-Control Products)
Pregnancy & Breastfeeding: Avoid unnecessary exposure, especially sprays and other products that can be inhaled. Animal studies raise additional concerns about exposure during development
Source: Synthetic
EWG Rating: N/A
D
D&C Red No. 33 (CI 17200)
Avoid
A synthetic red dye used to add color to cosmetics and personal care products. Testing of Red 33 has found small amounts of carcinogenic contaminants, including benzidine and 4-aminobiphenyl, that can be left behind during manufacturing. Because of this, the FDA sets strict limits on these contaminants and requires every batch of Red 33 used in the U.S. to be certified.
Commonly Found In: Beauty + Personal Care (lip products, cosmetics, skincare, hair products, toothpaste, mouthwash)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established from normal cosmetic use.
Source: Synthetic (azo dye)
EWG Rating: 5
DEA Cetyl Phosphate
Avoid
A synthetic emulsifier and surfactant used to improve texture and help oil and water mix together in cosmetic products. DEA-related ingredients may carry contamination concerns depending on manufacturing processes and may also be irritating for some people with sensitive skin.
Commonly Found In: Beauty (shampoos, conditioners, lotions, creams)
Pregnancy: Avoid, when possible, due to DEA-related concerns and possible manufacturing contamination.
Source: Synthetic
EWG Rating: 3
DEA Oleth 3 Phosphate
Avoid
A synthetic emulsifier and surfactant used in cleansers and personal care products to improve texture and formulation stability. Because it is derived from DEA and ethoxylated compounds, it may carry contamination concerns depending on manufacturing and purification processes. Ethoxylated ingredients may contain trace levels of 1,4-dioxane, a contaminant linked to health concerns.
Commonly Found In: Beauty (shampoos, facial cleansers, body washes)
Pregnancy: Avoid, when possible, due to DEA and ethoxylation concerns, including possible 1,4-dioxane contamination.
Source: Synthetic
EWG Rating: 1-5
Deceth-8
Avoid
A synthetic cleansing ingredient used in cleaners and personal care products. Deceth-8 is ethoxylated, which means 1,4-dioxane can remain during manufacturing if it isn't properly removed. This is a real concern with ethoxylated ingredients because 1,4-dioxane is a potential human carcinogen. It can also irritate sensitive skin.
Commonly Found In: Household + Beauty (laundry detergents, dish soaps, multi-surface cleaners, carpet cleaners, shampoos, body washes)
Pregnancy: Avoid, when possible, due to ethoxylation concerns and possible 1,4-dioxane contamination
Source: Synthetic
EWG Rating: N/A
Decyl Glucoside
Use in Moderation
A surfactant typically derived from coconut or corn sugars that is commonly used in gentler cleansers and low tox products. Compared to harsher surfactants, it is generally considered a milder option for both household and personal care products. Some people with very sensitive skin may still experience irritation depending on the formula and concentration used.
Commonly Found In: Beauty + Household (face washes, baby washes, shampoos, body washes, hand soaps, dish soaps, all-purpose cleaners)
Pregnancy: Lower concern when used in a well-formulated product and rinsed off. May still irritate sensitive skin.
Source: Naturally derived
EWG Rating: 2
Diazolidinyl Urea
Avoid
A synthetic preservative used to prevent microbial growth and extend shelf life in personal care products. This ingredient is considered a formaldehyde-releasing preservative, meaning it can slowly release small amounts of formaldehyde over time within a formula. Formaldehyde-releasing preservatives may contribute to irritation, sensitivity, or allergic reactions for some people, especially with repeated exposure.
Commonly Found In: Beauty (shampoos, conditioners, lotions, body washes, facial cleansers, moisturizers)
Pregnancy: Avoid due to formaldehyde-releasing preservative concerns.
Source: Synthetic
EWG Rating: 4
Dimethicone
Avoid
A silicone used to make skincare, makeup, and hair products feel smooth and silky. Dimethicone itself is considered lower concern, but testing has found that small amounts of cyclic silicones like D4 and D5 can remain from manufacturing. D4 has reproductive and hormone-related concerns, while D5 has also raised concerns around reproductive hormones and environmental persistence. How much remains depends on how the dimethicone is manufactured and purified.
Commonly Found In: Beauty (primers, foundations, moisturizers, sunscreens, conditioners, hair serums, anti-frizz products)
Pregnancy & Breastfeeding: Avoid when possible, due to potential contamination with cyclic silicones such as D4, which has reproductive toxicity concerns
Source: Synthetic (silicone-based polymer)
EWG Rating: 2-5
Dipropylene Glycol (1 Hydroxypropoxy)
Use in Moderation
A synthetic solvent commonly used to carry fragrance and improve the texture of beauty and personal care products. Dipropylene glycol itself is considered a lower concern, but the bigger issue is purity. EWG lists 1,4-dioxane and ethylene oxide as potential contaminants, which matters because both are linked to cancer. They aren't necessarily present in every product, and the risk depends on how the ingredient is manufactured and purified. Because dipropylene glycol can be found in several products used regularly, especially fragranced products, quality and repeated exposure matters.
Commonly Found In: Beauty + Personal Care (perfume, fragrance products, deodorant, skincare, haircare, and cosmetics)
Pregnancy & Breastfeeding: Generally considered lower concern on its own, but purity and repeated exposure through multiple products matters.
Source: Synthetic
EWG Rating: 1–3 (Depends on usage)
Disodium EDTA
Use in Moderation
A synthetic ingredient used to help products stay stable and work better. Disodium EDTA itself is considered lower concern and isn't easily absorbed through the skin, but how it is made and purified matters. Small amounts of NTA can be left behind during manufacturing, and NTA has caused cancer in animal studies at high doses. EDTA also doesn't break down easily in the environment and can bind to metals in waterways.
Commonly Found In: Beauty + Household (shampoos, conditioners, body washes, facial cleansers, laundry detergents, dish soaps, all-purpose cleaners)
Pregnancy: Lower concern in typical cosmetic use, but the overall formula should still be considered.
Source: Synthetic
EWG Rating: 2
E
Erythritol
Avoid
A sugar alcohol commonly used in sugar-free and reduced-sugar foods. Newer research has raised concerns that higher erythritol intake may increase platelet activity and make blood more likely to clot, although researchers are still working out what this means for long-term heart and stroke risk. It can also add up quickly because it is often used in several low-sugar foods, drinks, powders, and supplements throughout the day. Higher amounts can also cause diarrhea, bloating, and stomach upset.
Commonly Found In: Food + Beverage (protein powders, electrolyte mixes, sugar-free drinks, coffee sweeteners, gum, candy, baked goods, keto products, and flavored supplements)
Pregnancy & Breastfeeding: Research on frequent or higher intake during pregnancy is limited, so avoid or limit when possible.
Source: Naturally occurs in very small amounts but commercially produced through fermentation and purification
EWG Rating: 1
Ethanol
Use In Moderation
An alcohol used in beauty and household products to help ingredients dissolve, make products dry faster, or kill germs. Using it often can dry or irritate the skin, especially in products with higher amounts of alcohol. It is also found in several products people may use throughout the day, so sprays and aerosols can add unnecessary inhalation exposure. Ethanol can also help other ingredients penetrate the skin more easily, so what else is in the formula matters.
Commonly Found In: Beauty + Household (perfumes, toners, acne products, facial mists, hairsprays, hand sanitizers, disinfecting sprays, and cleaning products)
Pregnancy & Breastfeeding: Generally lower concern in normal topical use. Limit unnecessary inhalation from sprays and use products in a well-ventilated area.
Source: Plant-derived through fermentation or synthetically produced
EWG Rating: 1
Ethoxydiglycol
Avoid
AA synthetic solvent used to help ingredients dissolve, spread evenly, and absorb more easily into the skin. The bigger concern is what can be left behind during manufacturing. Ethoxydiglycol can contain impurities like ethylene oxide and 1,4-dioxane, which have serious health concerns including cancer. It can also contain small amounts of ethylene glycol, which is why its purity and concentration are regulated in some countries. Because it also helps other ingredients penetrate the skin, what else is in the formula matters too, especially when it is being used in several skincare or beauty products regularly.
Commonly Found In: Beauty (serums, anti-aging treatments, tanning products, moisturizers, toners, makeup, hair products, and some sprays)
Pregnancy & Breastfeeding: Avoid, when possible, because of the potential manufacturing impurities and its ability to increase penetration of other ingredients.
Source: Synthetic
EWG Rating: 5
Ethoxylated Alcohol / Ethoxylated Alcohol C12-C15
Avoid
A cleansing ingredient commonly used in laundry detergents and household cleaners. These ingredients go through ethoxylation, a process that can leave behind ethylene oxide and 1,4-dioxane if they aren't properly removed during manufacturing. Both have serious health concerns, including cancer. These contaminants are the main concern with ethoxylated ingredients, and how well the ingredient is manufactured and purified can affect how much remains in the finished material.
Commonly Found In: Household (laundry detergents, dish soaps, multi-surface cleaners, degreasers, floor cleaners, and industrial cleaners)
Pregnancy & Breastfeeding: Avoid when possible because of the potential for ethylene oxide and 1,4-dioxane contamination.
Source: Synthetic (ethoxylated compound)
EWG Rating: 2
Ethyl Acetate
Use In Moderation
A solvent commonly used in nail products and other quick-drying formulas. The bigger concern is breathing in the fumes, especially when using several nail products or spending a lot of time in poorly ventilated spaces. Higher exposure can irritate the eyes, nose and throat and cause headaches, dizziness or drowsiness.
Commonly Found In: Beauty (nail polish, nail polish remover, perfumes, cosmetics)
Pregnancy: Limiting repeated inhalation exposure during pregnancy and breastfeeding may help reduce overall exposure.
Source: Synthetic or naturally derived
EWG Rating: 1
Ethyl Alcohol (Ethanol)
Use In Moderation
An alcohol used to help beauty products dry quickly, dissolve ingredients, or kill germs. Frequent use can dry and irritate the skin, especially in products with higher amounts of alcohol. It can also show up in several products used throughout the day, so sprays and aerosols can add unnecessary inhalation exposure. What else is in the formula matters too, especially fragrance and the ingredients used to denature the alcohol.
Commonly Found In: Beauty + Household (perfumes, toners, facial mists, acne products, hairsprays, hand sanitizers, disinfectants, and cleaning sprays)
Pregnancy & Breastfeeding: Generally lower concern with normal topical use. Limit unnecessary inhalation from sprays and use in a well-ventilated area.
Source: Naturally derived or synthetic
EWG Rating:1
Ethyl Hexanediol
Use in Moderation
A synthetic ingredient used as a solvent in some beauty and personal care products. The bigger concern is skin irritation and sensitivity, especially in leave-on products or for people with sensitive or reactive skin. Animal studies have raised some developmental concerns at very high exposures, but those amounts were much higher than what someone would normally get from cosmetics.
Commonly Found In: Beauty (serums, moisturizers, cosmetics, sunscreens, skincare products)
Pregnancy:Typical cosmetic exposure is considered much lower than the amounts that caused developmental effects in animal studies. Limit unnecessary repeated exposure if you want to take a more cautious approach.
Source: Synthetic (typically petroleum derived)
EWG Rating: 3
Ethyl Lauroyl Arginate
Use In Moderation
A synthetic preservative and antimicrobial ingredient used to help prevent bacterial growth and extend shelf life in certain products. It may contribute to skin irritation or sensitivity for some individuals.
Concern is generally higher with repeated exposure through heavily fragranced or highly processed formulas containing multiple preservatives.
Commonly Found In: Household + Beauty (cleaning products, disinfecting products, personal care items, cosmetics)
Pregnancy: Generally considered lower concern in typical product use, though limiting unnecessary synthetic preservatives during pregnancy and breastfeeding may help reduce overall exposure.
Source: Synthetic
EWG Rating: 1-2
Ethylene Glycol Monobutyl Ether
Avoid
AA solvent used in cleaning products to cut through grease and grime. It can be absorbed through both the skin and breathing it in, making sprays and cleaners used regularly indoors more of a concern. Higher exposure can irritate the eyes and skin and affect red blood cells, with liver and kidney effects seen at higher amounts. Using several cleaning products containing it regularly can add to overall exposure.
Commonly Found In: Household (glass cleaners, degreasers, multi surface cleaners, floor cleaners, industrial cleaning products)
Pregnancy: Avoid when possible due to inhalation and VOC exposure concerns during pregnancy and breastfeeding.
Source: Synthetic
EWG Rating: N/A
Ethylhexylglycerin
Use In Moderation
A preservative booster and skin conditioning ingredient often used as an alternative to parabens in beauty and personal care products. While generally considered lower concern compared to some traditional preservatives, it may still contribute to irritation, redness, itching, or sensitivity in some people, especially those with reactive or allergy prone skin.
Concern is generally higher in leave on products used daily or formulas containing multiple preservatives and fragrance ingredients.
Commonly Found In: Beauty (skincare, makeup, deodorant, baby wipes, moisturizers, serums)
Pregnancy: Generally considered lower concern in typical cosmetic use, though sensitive individuals may still prefer to limit frequent exposure during pregnancy and breastfeeding.
Source: Naturally derived but synthetically processed
EWG Rating: 2
Ethylparaben
Avoid
A synthetic preservative used to help prevent bacteria and mold growth in beauty and personal care products. Ethylparaben belongs to the paraben family of preservatives, which have raised concerns because some parabens may mimic estrogen activity within the body. It may also contribute to irritation or sensitivity for some people.
Concern is generally higher with frequent daily exposure across multiple personal care products over time and less estrogenic concern than butyl/propyl parabens.
Commonly Found In: Beauty (lotions, moisturizers, cosmetics, shampoos, conditioners, skincare products)
Pregnancy: Avoid when possible due to endocrine and hormone disruption concerns.
Source: Synthetic
EWG Rating: 3
Eugenol
Use in Moderation
A fragrance compound naturally found in essential oils like clove, cinnamon, basil, and bay, although it can also be made synthetically. Eugenol is a known fragrance allergen and can cause irritation or allergic skin reactions, especially with repeated exposure or for people with sensitive skin, eczema, psoriasis, or fragrance sensitivities. Higher amounts taken internally can also be harmful to the liver, but that is a very different exposure than the small amounts typically used in beauty products.
Commonly Found In: Beauty + Household (perfumes, skincare, cosmetics, essential oil blends, fragranced products, dental products, and some household fragrances)
Pregnancy & Breastfeeding: Small amounts in properly formulated topical products are lower concern. Avoid concentrated internal use unless directed by a healthcare professional.
Source: Natural or synthetic
EWG Rating: 3
F
Farnesol
Avoid
A fragrance ingredient that occurs naturally in certain essential oils and can also be made synthetically. It is used to add scent and may also have deodorizing or antimicrobial properties. Farnesol is a known fragrance allergen and can cause skin sensitization, irritation, or allergic contact dermatitis, especially with repeated use or on sensitive skin.
Commonly Found In: Beauty (perfumes, deodorants, skincare, cosmetics, fragranced personal care products)
Pregnancy: Limiting unnecessary fragrance exposure during pregnancy and breastfeeding may help reduce overall exposure.
Source: Natural or synthetic
EWG Rating: 3
FD&C Dyes / Aluminum Lakes (Example: Red No. 40, Yellow No. 5 Aluminum Lake)
Avoid
Synthetic dyes and color additives used to make products appear brighter or more visually appealing. “Lake” dyes are created by combining synthetic colors with metals or mineral salts such as aluminum or calcium to create more stable pigments commonly used in beauty products, supplements, foods, and household products. Many FD&C dyes are petroleum or coal tar derived.
Some research and regulatory discussions have raised concerns around certain synthetic dyes and their potential effects on behavior, hyperactivity, neurological health, irritation, and allergic reactions in sensitive individuals. Concern is generally higher with frequent ingestion, lip products, supplements, and repeated cumulative exposure across multiple products.
Commonly Found In: Beauty + Supplements + Household (cosmetics, lipsticks, gummies, capsules, protein powders, cleaning products, soaps, detergents, colored personal care products)
Pregnancy: Avoid when possible due to unnecessary synthetic dye and cumulative exposure concerns.
Source: Synthetic (commonly petroleum or coal tar derived)
EWG Rating: N/A
Flavoring
Avoid
A broad term used to describe flavor ingredients, extracts, solvents, or chemical compounds added to foods and beverages to create or enhance flavor. Because “flavoring” or “natural flavors” can represent a mixture of many undisclosed ingredients, it lacks transparency and may include solvents, preservatives, processing aids, or other additives not individually disclosed on the label.
Concern is generally higher in ultra processed foods and beverages consumed frequently or daily.
Commonly Found In: Food + Beverage (protein powders, flavored drinks, supplements, candy, snacks, electrolyte products, processed foods)
Pregnancy: Limiting heavily flavored and ultra processed products during pregnancy and breastfeeding may help reduce overall exposure to unnecessary additives.
Source: Natural or synthetic
EWG Rating: N/A
Fluopyram
Avoid
A synthetic fungicide and nematicide used in agriculture to help control mold, mildew, fungal diseases, and crop pests. It is commonly applied to produce crops including apples, grapes, strawberries, potatoes, beans, and sugar beets. Regulatory agencies have raised concerns around potential carcinogenicity based on animal research.
Concern is generally higher with repeated dietary exposure through conventionally grown produce with pesticide residues.
Commonly Found In: Food (conventionally grown produce and agricultural crops)
Pregnancy: Avoid when possible, due to pesticide and potential carcinogenicity concerns.
Source: Synthetic (agricultural pesticide)
EWG Rating: N/A
Fluoride
Avoid
A mineral commonly added to toothpaste and dental products to help strengthen enamel and reduce cavities. While fluoride has long been used in conventional dentistry, more recent research and regulatory discussions have raised concerns around excessive cumulative exposure, especially during early development and childhood. Some studies have explored potential links between high fluoride exposure and neurological or developmental effects.
Commonly Found In: Beauty (toothpaste, mouthwash, dental treatments, oral care products)
Pregnancy: Limiting unnecessary fluoride exposure during pregnancy and early childhood may help reduce cumulative exposure concerns.
Source: Naturally occurring mineral or synthetically added compound
EWG Rating: N/A
Folic Acid
Use In Moderation
A synthetic form of vitamin B9 commonly added to fortified foods, supplements, and prenatal vitamins. Folic acid plays an important role in fetal development and prevention of neural tube defects during pregnancy. However, some people have difficulty efficiently converting synthetic folic acid into its active form within the body, especially those with certain genetic variations such as MTHFR polymorphisms.
Concern is generally higher with excessive intake from heavily fortified foods and supplements rather than occasional dietary exposure.
Commonly Found In: Food + Beverage + Supplements (fortified grains, cereals, breads, prenatal vitamins, multivitamins, nutrition drinks)
Pregnancy: Folate is important during pregnancy, though some individuals may prefer methylfolate or food based folate forms instead of high amounts of synthetic folic acid.
Source: Synthetic
EWG Rating: 1
Formalin
Avoid
A solution made from formaldehyde dissolved in water that is used in disinfectants, laboratories, manufacturing, and some vaccine manufacturing processes to help inactivate viruses or toxins during production. Formalin is a known carcinogen and strong respiratory irritant. Higher or repeated exposure may irritate the eyes, skin, nose, throat, and lungs, especially through inhalation.
Commonly Found In: Medical Products + Vaccine Manufacturing + Industrial + Household (laboratories, disinfectants, manufacturing, some vaccines, nail products, hair products, formaldehyde-releasing preservatives)
Pregnancy: Avoid due to carcinogenic possibilities and other health risks
Source: Synthetic (formaldehyde solution in water)
EWG Rating: 9
Fragrance
Avoid
A broad term used to describe a mixture of fragrance ingredients added to products to create scent. “Fragrance” or “parfum” can represent a blend of dozens or even hundreds of undisclosed chemicals, including solvents, preservatives, phthalates, allergens, and other fragrance compounds that are not individually disclosed on labels due to trade secret protections.
Concern is generally higher with repeated daily exposure, inhalation, indoor air exposure, candles, air fresheners, laundry products, perfumes, and leave-on personal care products. Fragrance ingredients may contribute to irritation, headaches, respiratory symptoms, hormone disruption concerns, or sensitivities in some individuals.
Commonly Found In: Beauty + Household (perfumes, skincare, cosmetics, candles, laundry detergents, air fresheners, cleaning products, personal care products)
Pregnancy: Avoid when possible due to concerns about cumulative fragrance and inhalation exposure during pregnancy and breastfeeding.
Source: Synthetic or mixed natural/synthetic fragrance blends
EWG Rating: N/A
Fructose
Use In Moderation
A naturally occurring sugar found in fruit, vegetables, and honey. However, the fructose used in processed foods and beverages is often highly refined and commonly derived from corn or sugar beets. Excessive intake of processed fructose, especially from sweetened beverages and ultra-processed foods, may contribute to blood sugar imbalance, fatty liver concerns, metabolic dysfunction, and increased inflammation over time.
Concern is generally higher with frequent intake from processed foods and beverages rather than naturally occurring fructose from whole fruits.
Commonly Found In: Food + Beverage (sweetened drinks, protein bars, candy, flavored yogurt, baked goods, processed snacks)
Pregnancy: Moderating heavily processed sugars during pregnancy and breastfeeding may help support blood sugar balance and overall health.
Source: Naturally occurring or commercially processed from corn or sugar beets
EWG Rating: 1
G
Gelatin
Use in Moderation
An animal-derived ingredient made from collagen and commonly used in foods, supplements, gummies, and capsules. Gelatin itself is generally considered lower concern, but where it comes from and how well it is made matters. Testing of collagen and gelatin products has found heavy metals like lead, arsenic, cadmium, and mercury, with levels varying between brands. Because these products may be consumed regularly, choosing brands that are transparent about sourcing and third-party test for heavy metals can help reduce exposure.
Commonly Found In: Supplements + Food & Beverage (capsules, gummies, marshmallows, gelatin desserts, collagen products, protein products, and broths)
Pregnancy & Breastfeeding: Generally considered lower concern, though sourcing and third-party testing for heavy metals matters for products used regularly.
Source: Animal-derived (from collagen)
EWG Rating: 1
GenX
Avoid
A man-made PFAS chemical used as a processing aid to manufacture certain fluoropolymers. GenX usually won't appear on an ingredient label because exposure is more commonly connected to industrial contamination, especially contaminated drinking water near manufacturing sites. Animal studies have raised concerns involving the liver, kidneys, immune system and development, along with possible cancer concerns.
Commonly Found In: Environmental + Industrial Exposure (contaminated drinking water and areas affected by PFAS manufacturing)
Pregnancy & Breastfeeding: Avoid or reduce exposure when possible because of developmental and immune concerns identified with GenX chemicals.
Source: Synthetic PFAS
EWG Rating: N/A
Geraniol
Use in Moderation
A naturally occurring fragrance compound found in essential oils such as rose, citronella, and geranium. While naturally derived, it may still trigger irritation or allergic reactions in sensitive individuals. Concern is generally greater with repeated exposure through fragranced leave-on products, perfumes, or products used on compromised skin barriers rather than occasional rinse-off exposure.
Commonly Found In: Beauty + Personal Care (perfumes, lotions, skincare, soaps, fragranced products)
Pregnancy: Generally considered lower concern in small amounts, though fragrance sensitivity and skin sensitivity may increase during pregnancy
Source: Natural or synthetic fragrance compound
EWG Rating: 3
Glutaraldehyde
Avoid
A strong disinfecting and sterilizing chemical that can irritate the skin, eyes, and respiratory system. It can also cause skin sensitization and trigger breathing problems with repeated exposure, especially when concentrated products are used in poorly ventilated areas. Glutaraldehyde is also used during the manufacturing of some vaccines to inactivate certain vaccine components, and very small residual amounts may remain in the finished vaccine.
Commonly Found In: Medical + Industrial + Vaccine Manufacturing (disinfectants, sterilizing solutions, medical equipment processing, industrial products, and some vaccines)
Pregnancy & Breastfeeding: Higher or repeated exposure, especially through inhalation, is the bigger concern during pregnancy. Residual amounts in vaccines are much smaller than occupational or concentrated disinfectant exposure.
Source: Synthetic aldehyde
EWG Rating: N/A
Glycerin
Use in Moderation
A moisturizing ingredient used in everything from skincare and toothpaste to foods, supplements and medications. Glycerin itself is considered low concern, but purity matters. Poorly controlled glycerin has been contaminated with toxic chemicals called diethylene glycol and ethylene glycol, which have caused serious poisonings when contaminated products were swallowed. Reputable manufacturers should test glycerin used in foods, supplements and medications for these contaminants.
Commonly Found In: Beauty + Food & Beverage + Supplements (lotions, skincare, cleansers, toothpaste, capsules, protein products & sweeteners)
Pregnancy & Breastfeeding: Glycerin itself is considered low concern during pregnancy and breastfeeding. For products that are swallowed, choosing reputable manufacturers that follow purity standards can help reduce contamination concerns.
Source: Plant-derived, animal-derived or synthetic
EWG Rating: 1-2
Glycolic Acid
Use in Moderation
An alpha hydroxy acid (AHA) used to exfoliate and improve skin texture. While commonly used in skincare, higher concentrations or layering multiple exfoliating products may irritate the skin barrier and increase sensitivity, especially with frequent use or strong chemical peels. Overuse may contribute to dryness, redness, inflammation, or increased sun sensitivity. Concern is generally related more to skin irritation and barrier disruption than systemic toxicity in standard cosmetic use.
Commonly Found In: Beauty (serums, exfoliants, peels, acne products, anti-aging skincare)
Pregnancy: Lower concentrations are generally considered compatible with pregnancy skincare, though stronger peels should be used cautiously
Source: Natural or synthetic
EWG Rating: 3-6
Glyoxal
Avoid
A chemical compound used in some cleaning products, disinfectants, industrial products, and preservatives. It can irritate the skin, eyes, and respiratory system and has raised concerns related to sensitization and repeated exposure. Inhalation and occupational exposure are generally considered more concerning than occasional incidental exposure because respiratory irritation may increase over time with repeated contact.
Commonly Found In: Household + Beauty (disinfectants, cleaners, preservatives, industrial products)
Pregnancy: Repeated inhalation or occupational exposure may be more concerning during pregnancy and around babies or children
Source: Synthetic aldehyde
EWG Rating: 9
Glyphosate
Avoid
A widely used herbicide used on conventional crops and for weed control. Glyphosate usually isn't listed on food labels because exposure can come from pesticide residues left on treated crops. Cancer is one of the bigger concerns. IARC classifies glyphosate as probably carcinogenic to humans, based on evidence from human, animal, and laboratory studies. Newer animal research has also found several types of tumors after long-term exposure. Research has raised additional concerns around hormone and reproductive effects, although the evidence in humans is still developing. Because exposure can come from several foods and environmental sources over time, overall exposure matters.
Commonly Found In: Food & Beverage (conventional grains, oats, wheat, legumes, soy, corn, processed foods)
Pregnancy: Reducing unnecessary pesticide exposure during pregnancy and early childhood may be beneficial due to developing body systems
Source: Synthetic herbicide/pesticide
EWG Rating: N/A
Grapefruit Seed Extract (Citrus Paradisi Seed Extract)
Use in Moderation
An extract made from grapefruit seeds and pulp that is often marketed for its antimicrobial properties. The bigger concern is product quality and what may actually be in the extract. Testing of some commercial grapefruit seed extracts has found undeclared synthetic antimicrobial ingredients, including benzalkonium chloride. This doesn't mean every grapefruit seed extract is contaminated, but third-party testing and transparent sourcing matter, especially for products that are swallowed.
Commonly Found In: Beauty + Supplements (skincare, preservatives, antimicrobial products, supplements)
Pregnancy: Use caution with heavily concentrated extracts or products without clear testing standards during pregnancy
Source: Natural extract
EWG Rating: 1
Grapeseed Oil
Avoid
An oil made from grape seeds that is high in polyunsaturated fats. Grapeseed oil itself isn't considered toxic, but how it is processed, stored and heated matters. Because it is high in polyunsaturated fats, it can oxidize more easily when exposed to heat, light and air. As the oil breaks down, it can form aldehydes, including some that can damage cells and DNA at higher exposures. Research has found aldehyde formation in grapeseed oil during heating, making it a less ideal choice for repeated or high-heat cooking.
Commonly Found In: Food & Beverage + Beauty (cooking oils, processed foods, skincare, haircare)
Pregnancy: Generally considered lower concern, though less processed oils may be preferable when possible
Source: Plant-derived oil
EWG Rating: 1
Guar Gum
Use in Moderation
A thickening ingredient derived from guar beans and commonly used in processed foods. While generally considered lower concern from a toxicity standpoint, some emerging research has explored potential links between refined guar gum products, gut microbiome changes, inflammation, gut barrier disruption, and increased susceptibility to colitis. Digestive symptoms such as bloating, gas, or stomach discomfort may also occur in sensitive individuals. Concern is generally greater with frequent intake through heavily processed foods rather than occasional exposure.
Commonly Found In: Food & Beverage + Beauty (protein powders, dairy alternatives, sauces, gluten-free foods, skincare)
Pregnancy: No strong pregnancy-specific toxicity concerns identified. Main concern is digestive tolerance
Source: Natural (from guar bean)
EWG Rating: N/A
Guar Hydroxypropyltrimonium Chloride
Avoid
A conditioning ingredient made from modified guar gum and commonly used to make hair feel softer and easier to manage. It can irritate the skin and eyes, and the concentrated ingredient can irritate the respiratory system or trigger allergy or asthma-like symptoms if inhaled. The amounts used in shampoos and conditioners are much lower than concentrated workplace exposure, making rinse-off products less concerning. Sprays and other products that can be breathed in are more of a concern.
Commonly Found In: Beauty + Hair Care (shampoos, conditioners, leave-in treatments, styling products, and some sprays)
Pregnancy & Breastfeeding: Generally lower concern in normal topical use. Products that create inhalation exposure may be worth limiting.
Source: Chemically modified guar gum
EWG Rating: 1
Gypsum
Avoid
A naturally occurring mineral (calcium sulfate) used in some food products to regulate texture, acidity, or calcium content. In food products, gypsum is typically listed on ingredient labels as calcium sulfate. It is also widely used in drywall, construction materials, agriculture, and industrial products. In food, it is generally considered lower concern in small amounts, though some individuals may still prefer limiting frequent intake of processed food additives overall. The greater concern with gypsum is typically related to occupational or inhalation exposure to gypsum dust, particularly in construction or industrial settings where respiratory irritation may occur.
Commonly Found In: Food & Beverage + Industrial Products (tofu, baked goods, tortillas, processed foods, calcium-fortified foods, drywall, construction materials)
Pregnancy: Generally considered lower concern in small food amounts, though some individuals may still prefer limiting unnecessary processed food additive exposure during pregnancy
Source: Natural mineral (calcium sulfate)
EWG Rating: 1
H
1,2-Hexanediol
Use in Moderation
A synthetic preservative and solvent used to improve product texture and stability in cosmetics and personal care products. It is generally considered lower concern in small amounts, though some individuals with sensitive skin may experience irritation to the skin or eyes, especially with frequent exposure or heavily formulated products.
Commonly Found In: Beauty (skincare, makeup, serums, creams, preservatives)
Pregnancy: Generally considered lower concern in standard cosmetic use, though sensitive individuals may still prefer limiting unnecessary cumulative preservative exposure
Source: Synthetic
EWG Rating: 1
Hexamethylindanopyran
Avoid
A synthetic fragrance ingredient commonly used to create musky scents in fragranced household and personal care products. Concern is generally tied to fragrance sensitivities, skin irritation, and cumulative exposure through heavily fragranced products. This is also a suspected endocrine disruptor. Synthetic fragrance compounds may also persist in the environment and bioaccumulate over time.
Commonly Found In: Household + Beauty (air fresheners, laundry products, perfumes, fragranced cleaners)
Pregnancy: Fragrance sensitivity and respiratory irritation may increase during pregnancy
Source: Synthetic fragrance compound
EWG Rating: N/A
Hexoxyethanol
Avoid
A synthetic glycol ether solvent commonly used in household cleaners and some personal care products. Glycol ethers have raised concerns related to respiratory irritation, skin irritation, and potential reproductive or developmental effects with repeated or high-level exposure in some studies. Concern is generally greater with inhalation exposure through sprays, fragranced cleaners, or poorly ventilated spaces rather than occasional topical exposure.
Commonly Found In: Household + Beauty (cleaners, degreasers, sprays, cosmetics)
Pregnancy: Some individuals may prefer limiting unnecessary cumulative exposure to glycol ethers during pregnancy due to emerging reproductive and respiratory concerns within this chemical class
Source: Synthetic
EWG Rating: F
Hexyl Cinnamal
Avoid
A synthetic fragrance ingredient commonly used to create floral or jasmine-like scents in perfumes, skincare, haircare, and fragranced personal care products. It is a known fragrance allergen that may contribute to skin irritation, sensitivities, or allergic reactions in some individuals, especially with repeated exposure through leave-on or heavily fragranced products. Some animal studies have also explored potential endocrine disruption and organ toxicity concerns at certain exposure levels. Concern is generally tied to cumulative fragrance exposure and repeated daily use.
Commonly Found In: Beauty + Personal Care (perfumes, lotions, skincare, fragranced cosmetics)
Pregnancy: Fragrance sensitivity and skin sensitivity may increase during pregnancy
Source: Synthetic fragrance compound
EWG Rating: 4
Hexylene Glycol
Avoid
A synthetic solvent and texture-enhancing ingredient commonly used in skincare, makeup, and personal care products. Hexylene glycol may contribute to skin irritation, inflammation, dermatitis, eye irritation, or respiratory irritation in some individuals, especially with repeated exposure or compromised skin barriers. Because it can help increase ingredient penetration, concern may be greater when combined with heavily formulated or fragranced products. Spray or aerosolized exposure may also increase respiratory irritation concerns.
Commonly Found In: Beauty (skincare, makeup, serums, cleansers)
Pregnancy: Some individuals may prefer limiting unnecessary cumulative exposure to synthetic solvents during pregnancy
Source: Synthetic
EWG Rating: 1
High Oleic Sunflower Oil
Use in Moderation
A more stable form of sunflower oil that is higher in monounsaturated fats and lower in omega-6 fatty acids than traditional sunflower oil. While generally considered a better option than heavily refined seed oils, processing methods, oxidation, and frequent intake through ultra-processed foods may still be concerns for some individuals. Standard sunflower oil is significantly higher in omega-6 linoleic acid and is generally more prone to oxidation than high-oleic versions. Concern is generally greater with processed food exposure and high-heat cooking than occasional use.
Commonly Found In: Food & Beverage (cooking oils, processed foods, packaged snacks, dressings)
Pregnancy: Generally considered lower concern, though minimally processed oils may be preferable when possible
Source: Natural (from sunflower seeds)
EWG Rating: N/A
High-Fructose Corn Syrup
Avoid
A highly refined sweetener commonly derived from corn and frequently used in processed foods and beverages. Concern is tied to excessive intake and cumulative dietary exposure, particularly through ultra-processed foods and sugary drinks. Frequent consumption has been associated with blood sugar imbalance, inflammation, fatty liver concerns, and increased risk of metabolic disease. It is also commonly sourced from conventional GMO corn.
Commonly Found In: Food & Beverage (soda, candy, sauces, packaged snacks, processed foods)
Pregnancy: Excessive added sugar intake during pregnancy may contribute to blood sugar imbalance and metabolic concerns
Source: Synthetic/Highly processed (commonly from corn)
EWG Rating: N/A
Homosalate
Avoid
A synthetic UV filter commonly used in chemical sunscreen products and SPF cosmetics. Some research has explored concerns surrounding hormone disruption, systemic absorption, bioaccumulation, and cumulative exposure with repeated sunscreen use. Emerging studies and regulatory reviews have also raised questions regarding potential endocrine activity and effects on hormone signaling at certain exposure levels.
Commonly Found In: Beauty (chemical sunscreens, SPF moisturizers, cosmetics with SPF)
Pregnancy: Some individuals may prefer limiting unnecessary exposure to chemical sunscreen filters during pregnancy due to emerging endocrine disruption concerns
Source: Synthetic
EWG Rating: 3-5
Hydrated Silica
Use in Moderation
A form of silicon dioxide commonly used in toothpaste, cosmetics, powders, and skincare products for texture, absorbency, or mild exfoliation. In standard toothpaste or cream-based products, hydrated silica is generally considered lower concern. The bigger concern is inhalation exposure from fine powders, or sprays, which may irritate the nose, throat, and lungs.
Commonly Found In: Beauty + Oral Care (toothpaste, powders, makeup, skincare)
Pregnancy: Generally considered lower concern in standard topical or oral care use
Source: Natural or synthetic silica derivative
EWG Rating: 1-2
Hydrocolloid
Use in Moderation
A moisture-absorbing material commonly used in pimple patches, blister bandages, and wound dressings. Hydrocolloid products are often made from ingredients such as gelatin, cellulose, pectin, and synthetic polymers. Concern is generally less about the hydrocolloid itself and more about undisclosed adhesives, plastic polymers, preservatives, or other synthetic materials used in some formulations.
Commonly Found In: Beauty + Medical Products (pimple patches, wound dressings, blister bandages)
Pregnancy: Generally considered lower concern in standard topical use
Source: Natural and synthetic materials
EWG Rating: 1
Hydrogen Peroxide
Use in Moderation
An antimicrobial ingredient commonly used for disinfecting, whitening, stain removal, and cleaning. While effective, frequent or concentrated exposure may irritate the skin, eyes, lungs, or oral tissues. Concern is generally greater with inhalation exposure, frequent use, or high concentrations than occasional diluted use.
Commonly Found In: Household + Beauty + Oral Care (disinfectants, whitening products, cleaners, hair dye, mouth products)
Pregnancy: Generally considered lower concern in diluted household use, though excessive inhalation or concentrated exposure should be minimized
Source: Synthetic
EWG Rating: 2-5
Hydrogenated Palm Kernel Oil or Palm Oil
Avoid
A heavily processed oil used to improve texture and shelf life in many packaged foods. Hydrogenation may create trans fats or increase processing concerns depending on the manufacturing method. Frequent intake of heavily processed oils has been associated with inflammation imbalance and cardiovascular concerns. Conventional palm oil production has also been linked to significant environmental and biodiversity concerns.
Commonly Found In: Food & Beverage (processed foods, baked goods, candy, packaged snacks, coffee creamers)
Pregnancy: Limiting frequent intake of heavily processed oils may be preferable during pregnancy as part of an overall nutrient-dense diet
Source: Natural oil, heavily processed
EWG Rating: 1-2
Hydrolyzed Vegetable Protein
Avoid
A highly processed flavor-enhancing ingredient made by chemically breaking down vegetable proteins such as soy, corn, or wheat. Depending on processing methods, it may contain free glutamates or other processing contaminants.
Commonly Found In: Food & Beverage (soups, sauces, snack foods, seasonings, processed meats)
Pregnancy: Frequent intake of heavily processed foods may increase cumulative additive exposure during pregnancy
Source: Highly processed (commonly from soy, corn, or wheat)
EWG Rating: 1
Hydrolyzed Wheat Protein/PVP Crosspolymer
Avoid
A synthetic film-forming ingredient made from hydrolyzed wheat protein combined with PVP, a petroleum-derived plastic polymer. It is commonly used in cosmetics and sunscreens to improve texture, adhesion, and water resistance. Concern is generally tied to cumulative exposure to synthetic polymers, irritation potential, and environmental persistence.
Commonly Found In: Beauty (sunscreen, haircare, makeup, long-wear cosmetics)
Pregnancy: Some individuals may still prefer limiting unnecessary cumulative exposure to synthetic polymers during pregnancy
Source: Synthetic (from wheat protein and PVP polymer)
EWG Rating: 1
Hydroxyacetophenone
Avoid
An ingredient used to help stabilize skincare and cosmetic products and boost preservative effectiveness. While often considered a lower concern ingredient, long-term research is still limited, and some individuals may experience irritation or sensitivities depending on the formulation.
Commonly Found In: Beauty (skincare, cosmetics, preservative systems)
Pregnancy: Some individuals may still prefer limiting unnecessary cumulative preservative exposure during pregnancy due to limited long-term research
Source: Synthetic or naturally derived
EWG Rating: 1
Hydroxy citronellal
Avoid
A synthetic fragrance ingredient commonly used in perfumes and fragranced personal care products. It is a known fragrance allergen that may contribute to skin irritation, sensitivities, or allergic reactions, especially with repeated exposure through leave-on fragranced products or heavily scented products used daily.
Commonly Found In: Beauty + Personal Care (perfumes, lotions, skincare, fragranced cosmetics)
Pregnancy: Fragrance sensitivity and skin sensitivity may increase during pregnancy
Source: Synthetic fragrance compound
EWG Rating: 3
Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
Avoid
A synthetic thickener and texture-enhancing ingredient commonly used in skincare and cosmetic products to improve texture and stability. It is often petroleum-derived, and concern is generally tied to cumulative exposure to synthetic polymers, petroleum-derived ingredients, and potential skin sensitivities with frequent use.
Commonly Found In: Beauty (serums, moisturizers, gels, sunscreens, skincare products)
Pregnancy: Some individuals may prefer limiting unnecessary cumulative exposure to petroleum-derived synthetic polymers during pregnancy
Source: Synthetic (commonly petroleum-derived)
EWG Rating: 1
Hydroxyethyl piperazine Ethane Sulfonic Acid (HEPES)
Avoid
A synthetic buffering ingredient used to stabilize pH and enhance exfoliation in some skincare products. While it is commonly used in anti-aging and exfoliating products, long-term research is still limited. Some studies have explored potential oxidative stress or free radical formation depending on the formulation and exposure conditions. Concern may be greater with frequent use in heavily exfoliating skincare routines or on compromised skin barriers.
• Commonly Found In: Beauty (serums, exfoliants, anti-aging skincare products)
• Pregnancy: Limited research is available regarding pregnancy exposure
• Source: Synthetic
• EWG Rating: N/A
I
Isocetith-20
Avoid
An emulsifier and surfactant used to help oil and water mix and improve the texture of beauty products. Isoceteth-20 is ethoxylated, a manufacturing process that can leave behind small amounts of ethylene oxide and 1,4-dioxane if they aren't properly removed. Both have serious health concerns, including cancer, making manufacturing and purification important.
Commonly Found In: Beauty (toners, serums, creams, cleansers, hair products)
Pregnancy & Breastfeeding: Avoid when possible because of the potential contamination concerns tied to ethoxylation.
Source: Synthetic, ethoxylated
EWG Rating: 1–2
Isobutane
Avoid
A gas commonly used as a propellant in aerosol products. The biggest concern is breathing it in, especially when you use several spray products like dry shampoo, deodorant, and hairspray regularly or in poorly ventilated spaces. Purity also matters because isobutane can contain 1,3-butadiene as an impurity, which has serious health concerns, including cancer. Cosmetic-grade isobutane should meet limits for this contaminant.
Commonly Found In: Beauty + Household (dry shampoo, aerosol deodorant, hairspray, shaving products, and other aerosol sprays)
Pregnancy & Breastfeeding: Limiting unnecessary inhalation from frequently used aerosol products can help reduce exposure.
Source: Hydrocarbon gas, commonly petroleum-derived
EWG Rating: 3–7 depending on use and contamination concerns
Isobutylparaben
Avoid
A synthetic preservative used to help prevent mold and bacteria growth in cosmetics and personal care products. Parabens have raised concerns due to their endocrine-disrupting activity and ability to mimic estrogen in some studies. Concerns are tied to repeated, cumulative exposure through multiple personal care products used daily.
Commonly Found In: Beauty + Personal Care (lotions, makeup, skincare, haircare products)
Pregnancy: Some individuals may prefer limiting unnecessary cumulative exposure to parabens during pregnancy due to emerging hormone disruption concerns
Source: Synthetic preservative
EWG Rating: 10
Isoeugenol
Avoid
A fragrance ingredient that can be made synthetically or naturally found in some essential oils. Isoeugenol is a known skin allergen and is restricted in cosmetics because of its ability to cause allergic reactions. There are also cancer concerns. IARC classifies isoeugenol as possibly carcinogenic to humans after long-term animal studies found increased tumors, including liver tumors in mice. Because it can show up across several fragranced products used regularly, overall exposure matters.
Commonly Found In: Beauty + Household (perfume, deodorant, body spray, lotions, soaps, shampoo, hair products, and fragranced household products)
Pregnancy & Breastfeeding: Best avoided when possible because of its allergy concerns and unresolved cancer concerns.
Source: Natural or synthetic; naturally occurs in some essential oils
EWG Rating: 8
Isomalto-Oligosaccharides (IMO)
Use in Moderation
A processed sweetener made from starch and commonly added to protein bars, supplements, and foods marketed as low-sugar or high-fiber. Even though IMO may be listed or marketed as a fiber, some forms can still raise blood sugar significantly. How much it raises blood sugar depends on how the IMO is made and how much digestible sugar it contains. Larger amounts may also cause gas, bloating, or digestive discomfort.
Commonly Found In: Food + Supplements (protein bars, protein products, low-sugar snacks, supplements, and sweeteners)
Pregnancy & Breastfeeding: Generally considered lower concern, though blood sugar response and digestive tolerance still matter.
Source: Processed from starch, commonly corn or tapioca
EWG Rating: N/A
Isopropanol (Isopropyl Alcohol)
Use in Moderation
An alcohol used as a solvent, disinfectant, and antiseptic. Frequent use can dry and irritate the skin, while breathing higher amounts can irritate the eyes, nose and throat and cause headaches, dizziness or drowsiness. Exposure can add up when used regularly in disinfectants, sprays, and cleaning products, especially in poorly ventilated spaces.
Commonly Found In: Household + Medical + Beauty (rubbing alcohol, disinfectants, cleaners, sanitizers, sprays, cosmetics)
Pregnancy & Breastfeeding: Normal occasional use is generally a lower concern. Avoid unnecessary exposure to concentrated or repeated inhalation.
Source: Synthetic
EWG Rating: 2
Isopropyl paraben
Avoid
A synthetic preservative used to help prevent mold and bacterial growth in cosmetics and personal care products. Isopropylparaben is a longer-chain paraben, which has raised greater concern for endocrine-disrupting activity and estrogen-mimicking effects than some shorter-chain parabens. Concern increases with repeated cumulative exposure through multiple personal care products used daily.
Commonly Found In: Beauty + Personal Care (lotions, makeup, skincare, haircare products)
Pregnancy: avoid due to unnecessary cumulative exposure to parabens during pregnancy due to emerging hormone disruption concerns
Source: Synthetic preservative
EWG Rating: 10
J
K
Konjac Root Gum
Use in Moderation
A thickening ingredient made from konjac root and commonly used to improve the texture of foods and supplements. Konjac itself is generally considered a lower concern, but larger or more frequent amounts can cause gas, bloating, diarrhea, or constipation in some people. Source and purity also matters because konjac can contain heavy metals like lead and arsenic, making quality and testing more important for products used regularly. Concentrated konjac supplements can also swell significantly when mixed with water and should always be taken with enough liquid.
Commonly Found In: Food & Beverage + Supplements (konjac noodles, gummies, supplements, dairy alternatives, sauces, and processed foods)
Pregnancy & Breastfeeding: Generally considered lower concern in normal food amounts. Larger supplemental amounts may cause digestive issues, and product quality and proper hydration matters.
Source: Plant-derived (konjac root)
EWG Rating: N/A
L
Lactic Acid
Use in Moderation
An acid used as a preservative, pH adjuster, flavoring agent, and exfoliating ingredient in food and skincare products. It is often produced through the fermentation of sugars such as beet sugar, cane sugar, corn, or tapioca. Higher-strength skincare products may irritate sensitive skin, and some sources may be derived from GMO crops depending on manufacturing practices. Non-GMO and USDA Organic sources may help reduce sourcing concerns.
Commonly Found In: Food & Beverage + Beauty (processed foods, supplements, skincare, exfoliants, cleansers)
Pregnancy: Lower concentrations are considered lower concern, though stronger exfoliating products may increase skin sensitivity during pregnancy
Source: Naturally derived or synthetic/fermentation-derived
EWG Rating: 2-5
Lanolin
Use in Moderation
An animal-derived moisturizing ingredient obtained from sheep’s wool that is commonly used in skincare and lip products. While effective for dry skin, it may cause irritation or allergic reactions in some individuals, especially those with wool allergies or sensitive skin. Depending on purification and sourcing, lanolin may also contain pesticide or solvent residues.
Commonly Found In: Beauty + Personal Care (lip balm, moisturizers, nipple creams, ointments)
Pregnancy: Purified forms are considered lower concern, though sensitivities may vary by individual
Source: Animal-derived (from sheep’s wool)
EWG Rating: 1
Lauramide DEA
Avoid
A surfactant and foaming ingredient made from lauric acid and diethanolamine (DEA) that is used to improve lather and texture in personal care products. DEA-related ingredients may contain nitrosamine contamination depending on formulation and manufacturing methods. Nitrosamines are compounds linked to carcinogenicity concerns. It may also contribute to skin irritation or sensitivities, especially with frequent exposure.
Commonly Found In: Beauty + Personal Care (shampoos, body washes, facial cleansers)
Pregnancy: Avoid if you are choosing to limit unnecessary exposure to DEA-related ingredients and potential nitrosamine contamination during pregnancy
Source: Synthetic
EWG Rating: 1-5
Laureth-7
Avoid
An ethoxylated cleansing and emulsifying ingredient commonly used in skincare, cosmetics, and personal care products to help oil and water blend together. While considered low concern on its own, the ethoxylation process may introduce trace amounts of 1,4-dioxane and ethylene oxide if manufacturing and purification are not well controlled. Although many manufacturers reduce these impurities, ingredient labels do not disclose purification practices. I generally prefer products that use non-ethoxylated alternatives when available.
Commonly Found In: Beauty + Personal Care (cleansers, moisturizers, lotions, makeup)
Pregnancy: Generally considered low concern itself for topical use during pregnancy, however, if you choose to reduce the risk of contamination, I would avoid this ingredient.
Source: Typically derived from coconut or palm-based fatty alcohols through ethoxylation.
EWG Rating: 2
Lauryl Glucoside
Use in Moderation
A cleansing ingredient commonly derived from sugar and coconut or palm oils that is used in soaps, cleansers, shampoos, and detergents. While often marketed as a gentler surfactant, it may still cause dryness, irritation, or sensitivities in some individuals, especially with frequent use, concentrated products, or compromised skin barriers such as eczema or psoriasis. Concern may be greater in laundry detergents or fabric products where residue can remain in contact with the skin for longer periods of time compared to rinse-off products like hand soap.
Commonly Found In: Household + Beauty (soaps, detergents, cleansers, shampoos)
Pregnancy: Lower concern, though sensitive skin may become more reactive during pregnancy
Source: Naturally derived or synthetic
EWG Rating: 1-2
Limonene
Use in Moderation
A fragrance compound naturally found in citrus peels and many essential oils. While naturally derived, limonene can oxidize when exposed to air, which may increase the risk of skin irritation, sensitivities, or allergic reactions in some individuals. Repeated exposure through fragranced products or oxidized essential oils may increase this concern.
Commonly Found In: Household + Beauty (cleaners, essential oils, fragranced products, skincare)
Pregnancy: Fragrance and skin sensitivity may increase during pregnancy
Source: Naturally derived (commonly from citrus fruits)
EWG Rating: 4-5
Linalool
Use in Moderation
A fragrance compound naturally found in lavender and many other essential oils. Linalool can oxidize over time, which may increase the risk of skin irritation, sensitivities, or allergic reactions in some individuals. Repeated exposure through fragranced or leave-on products may increase this concern.
Commonly Found In: Beauty + Household (skincare, perfumes, cleaners, fragranced products, essential oils)
Pregnancy: Fragrance and skin sensitivity may increase during pregnancy
Source: Naturally derived (commonly from essential oils)
EWG Rating: 3-4
Linalyl Acetate
Use in Moderation
A fragrance ingredient found naturally in essential oils like lavender, but it can also be made synthetically. The bigger concern is what happens when it is exposed to air over time. As linalyl acetate oxidizes, it can form compounds that are more likely to cause allergic skin reactions. This may be more of a concern in older products that have been opened repeatedly, especially for people with sensitive skin, eczema, or fragrance allergies.
Commonly Found In: Beauty + Household (perfume, skincare, lotions, deodorant, haircare, soaps, essential oil products, and fragranced household products)
Pregnancy & Breastfeeding: Generally considered lower concern. Skin sensitivity and repeated exposure to fragranced products are the bigger concerns.
Source: Natural or synthetic; naturally found in essential oils like lavender
EWG Rating: 4
Linear Alcohol Ethoxylate
Avoid
A synthetic surfactant used in cleaning and household products to help remove oils and dirt. Because it is an ethoxylated ingredient, manufacturing may result in contamination with impurities such as 1,4-dioxane or ethylene oxide depending on purification methods. Repeated exposure through household cleaners and heavily formulated products may increase this concern.
Commonly Found In: Household (laundry detergents, cleaners, degreasers, dish products)
Pregnancy: Avoid to limit unnecessary cumulative exposure to ethoxylated ingredients during pregnancy
Source: Synthetic (ethoxylated surfactant)
EWG Rating: 1-2
Linear Alkyl Benzene Sulfonates (LAS)
Use In Moderation
A synthetic cleaning ingredient used to help break down grease and dirt. LAS can irritate the skin and eyes, especially with concentrated or repeated exposure, and breathing in higher amounts can irritate the respiratory system. It does break down fairly well when oxygen is present but can take much longer to break down in certain wastewater and sediment environments. Because LAS is used so widely in cleaning products, this is more of an environmental concern than a major human health concern.
Commonly Found In: Household (laundry detergent, dishwashing products, all-purpose cleaners, and degreasers)
Pregnancy & Breastfeeding: Generally considered lower concern with normal household use. Limit breathing in sprays or detergent dust and avoid unnecessary contact with concentrated products.
Source: Synthetic (typically petroleum-derived)
EWG Rating: N/A
Linoleamide MEA
Avoid
A surfactant and emulsifying ingredient made from linoleic acid and monoethanolamide (MEA) that is used to improve texture and stability in personal care products. MEA-related ingredients may contribute to skin irritation or sensitivities and can raise concerns regarding nitrosamine contamination depending on formulation and manufacturing methods.
Commonly Found In: Beauty + Personal Care (shampoos, conditioners, moisturizers, cleansers)
Pregnancy: Avoid to limit unnecessary exposure to MEA-related ingredients and potential nitrosamine contamination during pregnancy
Source: Synthetic
EWG Rating: 4
M
m-Aminophenol (3-Aminophenol)
Avoid
A synthetic dye mainly used in permanent hair color. It is a known skin allergen and can cause sensitivity or allergic reactions, especially with repeated exposure. There are also some concerns around organ toxicity and limited evidence of cancer concerns, although it is not considered likely to cause cancer in humans.
Commonly Found In: Beauty (permanent hair dye and other hair-coloring products)
Pregnancy & Breastfeeding: Avoid when possible. There isn't strong evidence of reproductive or developmental toxicity, but it is still a sensitizing hair-dye chemical with other health concerns.
Source: Synthetic (coal-tar-derived hair dye)
EWG Rating: 8
Magnesium Chloride
Use in Moderation
A form of magnesium commonly sourced from seawater or mineral-rich salt water and used in supplements, electrolytes, and topical magnesium products. Magnesium chloride itself is considered lower concern, but source and purity matters. Heavy metals like lead, arsenic, and mercury are recognized impurities that manufacturers have to control, making third-party testing more important for supplements and electrolyte products that are used regularly. Larger supplemental amounts can also cause loose stools or digestive discomfort.
Commonly Found In: Food & Beverage + Supplements + Beauty (magnesium supplements, electrolytes, magnesium sprays, bath flakes, deodorant, and personal care products)
Pregnancy & Breastfeeding: Generally considered lower concern when used appropriately. Quality and testing matters more for products that are swallowed regularly.
Source: Naturally derived or manufactured, commonly sourced from seawater or mineral-rich brines
EWG Rating: 1
Magnesium Oxide
Use in Moderation
A common, inexpensive form of magnesium used in supplements and antacids. Magnesium oxide isn't absorbed as well as forms like magnesium citrate or chloride, and larger amounts are more likely to cause diarrhea, cramping, or digestive upset. Purity also matters because lead and arsenic are recognized impurities that manufacturers have to control, making quality and testing more important for supplements used regularly.
Commonly Found In: Supplements + OTC Products (magnesium supplements, multivitamins, antacids, and laxative products)
Pregnancy & Breastfeeding: Generally considered lower concern when used appropriately. A better absorbed form may be more useful when magnesium is being taken specifically to meet nutritional needs.
Source: Mineral-derived or manufactured
EWG Rating: 1
Magnesium Silicate (Talc)
Avoid
A mineral commonly known as talc that is used in supplements, powders, and cosmetics for texture and moisture absorption. Talc contamination with asbestos has raised concerns because asbestos exposure has been linked to cancer and respiratory disease. Inhalation exposure from loose powders is considered a bigger concern than limited topical exposure.
Commonly Found In: Beauty + Supplements (powders, pressed makeup, capsules, personal care products)
Pregnancy: Avoid if you are choosing to limit unnecessary talc or inhalation exposure during pregnancy
Source: Naturally derived mineral
EWG Rating: 8
Magnesium Stearate
Use in Moderation
An ingredient commonly added to supplements to keep powders from sticking to equipment during manufacturing. Magnesium stearate itself is considered lower concern, but where it comes from and how well it is made matters. It can be made from different vegetable oils or animal fats, including hydrogenated oils. Heavy metals like lead, arsenic, cadmium, and nickel are also recognized impurities that manufacturers have to control, making quality and testing more important in supplements taken regularly.
Commonly Found In: Supplements + Pharmaceuticals + Food & Beverage (capsules, tablets, powders, medications, and some processed foods)
Pregnancy & Breastfeeding: Generally considered lower concern in the small amounts typically used. Quality and sourcing matters more with products taken regularly.
Source: Made from magnesium and fatty acids that can come from vegetable oils or animal fats
EWG Rating: 1
Malic Acid (D-Malic Acid)
Use in Moderation
A naturally occurring acid found in fruits such as apples and commonly added to foods, drinks, supplements, and personal care products to create a tart flavor or adjust acidity. Malic acid is generally considered lower concern in normal amounts, but concentrated or frequent exposure can irritate the mouth, skin, or eyes. In acidic drinks and candies, repeated exposure can also contribute to tooth enamel erosion.
Commonly Found In: Food + Beverage + Supplements + Beauty (candy, flavored drinks, drink mixes, gummies, supplements, skincare and exfoliating products)
Pregnancy & Breastfeeding: Generally considered lower concern in normal food amounts. There is limited pregnancy-specific research on larger supplemental amounts
Source: Naturally occurs in fruits and plants; commercially produced malic acid is typically manufactured
EWG Rating: 1
Maltitol
Use In Moderation
A sugar alcohol commonly used in sugar-free and low-sugar foods. Some of the maltitol you eat isn't absorbed and instead gets fermented by bacteria in the gut, which can cause gas, bloating, cramping, or diarrhea, especially in larger amounts. It can also still raise blood sugar. Long-term animal studies have also found changes in the adrenal glands, including adrenal hyperplasia and tumors at the highest doses.
Commonly Found In: Food & Beverage (protein bars, sugar-free candy, chocolate, baked goods, and low-sugar foods)
Pregnancy & Breastfeeding: Generally considered lower concern in normal amounts, but larger amounts may cause digestive upset
Source: Made from maltose, typically from starch
EWG Rating: 1
Maltodextrin
Use in Moderation
A highly processed carbohydrate commonly added to packaged foods and supplements as a thickener or filler. It is broken down into glucose very quickly and can cause a fast spike in blood sugar. Research in humans has also found that maltodextrin can change gut bacteria and other parts of gut function, although we still don't know what these changes mean for long-term gut health. This is different from Maltodextrin/VP Copolymer, a separate ingredient used mainly in cosmetics.
Commonly Found In: Food & Beverage + Supplements (protein powders, electrolyte powders, snacks, flavored products, and processed foods)
Pregnancy & Breastfeeding: Generally considered lower concern in normal amounts
Source: Made from starch, commonly corn, rice, potato, or tapioca
EWG Rating: 1
MEA Laureth Sulfate
Avoid
A cleansing and foaming ingredient used in personal care and household products. It is ethoxylated, which means manufacturing can leave behind 1,4-dioxane and ethylene oxide, two contaminants linked to cancer. There are also manufacturing restrictions in place to control nitrosamines, another group of potentially harmful contaminants. MEA-Laureth Sulfate can also irritate the skin and eyes, especially in more concentrated products.
Commonly Found In: Household + Beauty (cleaners, detergents, shampoos, soaps, and hair products)
Pregnancy & Breastfeeding: Avoid when possible because of the potential contaminants associated with how this ingredient is made
Source: Synthetic, ethoxylated surfactant
EWG Rating: 1–5 depending on usage and manufacturing
Melaleuca Alternifolia Leaf Oil (Tea Tree)
Use in Moderation
An essential oil distilled from tea tree leaves that is commonly used for its antimicrobial properties in skincare and personal care products. While many individuals tolerate it well, concentrated or oxidized tea tree oil may contribute to skin irritation, sensitivities, or allergic reactions in some individuals.
Commonly Found In: Beauty + Personal Care (skincare, acne products, shampoos, essential oil blends)
Pregnancy: Essential oils may increase skin sensitivity during pregnancy depending on concentration and exposure
Source: Naturally derived (from tea tree leaves)
EWG Rating: 4-6
Menthol
Use in Moderation
A cooling ingredient naturally found in peppermint or made synthetically. Menthol can irritate the skin and eyes and may cause an allergic reaction in some people, especially with repeated use or in more concentrated products. People with sensitive skin or fragrance allergies may be more likely to react to it.
Commonly Found In: Beauty + Personal Care (lip products, muscle rubs, oral care, skincare, shampoos, and cooling products)
Pregnancy & Breastfeeding: Generally considered lower concern when used as directed
Source: Naturally derived or synthetic
EWG Rating: 3
Menthyl Lactate
Use in Moderation
A cooling ingredient made from menthol and lactic acid and commonly used in skincare and personal care products. It is generally considered lower concern in the amounts used in cosmetics, but it may irritate sensitive skin, especially in more concentrated products or on an already irritated skin barrier. High-dose animal studies have also found changes in the liver, although these amounts are much higher than what you would normally be exposed to in personal care products. It can also be harmful to aquatic life with long-lasting effects.
Commonly Found In: Beauty + Personal Care (skincare, lip products, cooling creams, haircare, and oral care)
Pregnancy & Breastfeeding: Generally considered lower concern when used as directed
Source: Made from menthol and lactic acid
EWG Rating: 1
Methyl Alcohol
Avoid
Also known as methanol, this industrial alcohol is used in cleaners, solvents, fuels, and manufacturing products. Methanol is highly toxic in larger amounts and may contribute to headaches, dizziness, respiratory irritation, nervous system effects, vision damage, or poisoning with significant exposure. The biggest concern is that the body converts methanol into toxic compounds such as formaldehyde and formic acid after exposure. Inhalation, ingestion, and repeated concentrated exposure are considered the biggest concerns.
Commonly Found In: Household + Industrial (window cleaners, solvents, fuels, manufacturing products)
Pregnancy: Avoid if you are choosing to limit potential respiratory, nervous system, and visual effects
Source: Synthetic
EWG Rating: 3-6
Methyl Di-T-Butyl Hydroxyhydrocinnamate
Use In Moderation
A synthetic antioxidant used to keep products from breaking down or going rancid. Animal studies have found changes in the liver with repeated exposure at much higher amounts than what you would normally get from personal care products. The small amount in one product is considered lower concern, but this ingredient can show up in several products used regularly, so overall exposure can add up. Current research doesn't show that normal everyday exposure causes these same effects in people.
Commonly Found In: Household + Beauty (laundry products, cleaners, fragrance, cosmetics, and personal care products)
Pregnancy & Breastfeeding: No specific reproductive or developmental concern has been established at normal product exposure
Source: Synthetic antioxidant
EWG Rating: 2
Methyl Di isopropyl Propionamide (WS-23)
Avoid
A synthetic ingredient used to give products a cooling sensation without using menthol. Animal studies have found kidney effects with repeated exposure, along with changes in the liver and nervous system at higher amounts. These studies used much higher amounts than what you would normally be exposed to in personal care products, but there still isn't enough research to know what repeated, long-term exposure may look like in humans. This is especially worth considering in products used in or around the mouth where small amounts may be swallowed. Recent risk assessments continue to use the kidney and liver findings when evaluating WS-23 exposure.
Commonly Found In: Beauty + Personal Care (toothpaste, oral care, lip products, skincare, cooling products, and some hair products)
Pregnancy & Breastfeeding: Avoid when possible. There isn't enough research to know what repeated exposure may mean during pregnancy or breastfeeding.
Source: Synthetic cooling agent
EWG Rating: 1
Methyl eugenol (Eugenyl Methyl Ether)
Avoid
A fragrance compound that can occur naturally in certain essential oils or be made synthetically. Methyl eugenol is reasonably anticipated to be a human carcinogen based on animal studies, where exposure caused tumors in several organs. Our bodies can also break methyl eugenol down into compounds that can react with DNA. Because it can be part of fragrance mixtures, exposure may also come from several regularly used fragranced products.
Commonly Found In: Beauty + Household (perfumes, fragranced skincare, cosmetics, soaps, detergents, air fragrance products, and some essential oils)
Pregnancy & Breastfeeding: Avoid when possible because of its carcinogenicity concerns.
Source: Naturally occurring or synthetic
EWG Rating: N/A
Methyl Gluceth-20
Avoid
An ingredient used to help moisturize and improve the feel of skincare and personal care products. It is made using ethoxylation, a process that can leave behind 1,4-dioxane, a contaminant linked to cancer. How much is left behind depends on how well the ingredient is purified, and that isn't something you can tell by looking at an ingredient label.
Commonly Found In: Beauty + Personal Care (skincare, moisturizers, cleansers, shampoos, conditioners, hair products, and body products)
Pregnancy & Breastfeeding: Avoid when possible because of the potential for 1,4-dioxane contamination from manufacturing, not because Methyl Gluceth-20 itself has been shown to cause reproductive harm.
Source: Synthetic, ethoxylated ingredient
EWG Rating: 1-2
Methyl Salicylate (Oil of Wintergreen)
Avoid
An ingredient used in fragrance and in muscle and pain-relief products to create a warming sensation. Methyl Salicylate can be absorbed through the skin and converted in the body to salicylic acid, which is related to aspirin. High exposure can cause salicylate poisoning, and children are especially vulnerable. There are also reproductive and developmental concerns based on animal studies, and European regulators classify Methyl Salicylate as a suspected reproductive toxicant. It can also cause skin allergies and irritation.
Commonly Found In: Beauty + Personal Care (muscle rubs, pain-relief creams, balms, liniments, fragrance products and products containing wintergreen oil)
Pregnancy & Breastfeeding: Avoid. Methyl Salicylate can be absorbed through the skin, converted to salicylate and cross the placenta. Because of the reproductive and developmental concerns and the potential for exposure to add up from different products, avoiding unnecessary exposure during pregnancy and breastfeeding is the better option.
Source: Naturally found in wintergreen and some other plants or made synthetically
EWG: 9
Methylchloroisothiazolinone (MCI)
Avoid
A synthetic preservative used to prevent bacteria and mold from growing in products. The biggest concern with Methylchloroisothiazolinone is skin sensitization and allergic contact dermatitis. It is a well-established skin allergen and can cause someone to become sensitized, meaning future exposure may trigger an allergic skin reaction even at very small amounts. European safety assessments have identified the MCI/MI preservative mixture as a significant contact allergen and restrict its use in cosmetics.
Commonly Found In: Household + Beauty (cleaners, laundry products, liquid hand soap, shampoo, conditioner, body wash and other personal care products)
Pregnancy & Breastfeeding: Avoid. There isn't strong evidence that normal exposure causes reproductive or developmental harm, but because MCI is a potent skin sensitizer and isn't necessary in personal care or household products, it's an unnecessary exposure that's easy to avoid
Source: Synthetic preservative
EWG Rating: 6
Methyldihydrojasmonate
Use in Moderation
A synthetic fragrance ingredient used to give products a floral or jasmine-like scent. It can cause skin sensitivity or an allergic reaction in some people, especially with repeated exposure. It can also show up in several products you use every day, so fragrance exposure can add up.
Commonly Found In: Beauty + Personal Care and Household (perfume, deodorant, lotion, skincare, shampoo, conditioner, body wash, laundry products, cleaners and air fresheners)
Pregnancy & Breastfeeding: There isn't strong evidence of reproductive or developmental harm, but limiting unnecessary fragrance exposure can help reduce overall exposure from multiple products.
Source: Synthetic fragrance ingredient
EWG Rating: 3
Methylene Glycol
Avoid
A form of formaldehyde found in some hair straightening and smoothing treatments. When these products are heated with a blow dryer or flat iron, they can release formaldehyde gas into the air where it can be breathed in. Formaldehyde is a known human carcinogen and can also irritate the eyes, nose, throat and lungs and cause coughing, wheezing, skin reactions and allergic sensitivity. This is especially concerning with salon treatments because heat can significantly increase the amount of formaldehyde released into the air.
Commonly Found In: Beauty + Personal Care (keratin treatments, Brazilian-style blowouts, hair straightening and smoothing treatments)
Pregnancy & Breastfeeding: Avoid, especially heated hair-smoothing treatments, to reduce unnecessary exposure to formaldehyde gas.
Source: Formaldehyde dissolved/reacted in water
EWG Rating: N/A
Methylisothiazolinone (MI)
Avoid
A preservative used to prevent bacteria and mold growth in household and personal care products. It is a well-known skin sensitizer and has been linked to allergic reactions, irritation, and contact dermatitis. It also may be neurotoxic.
Commonly Found In: Household + Beauty (cleaners, shampoos, soaps, skincare, personal care products)
Pregnancy: Avoid. MI is a strong skin sensitizer, and research on repeated exposure during pregnancy and breastfeeding is limited.
Source: Synthetic preservative
EWG Rating: 7
Methylparaben
Avoid
A preservative used to keep beauty and personal care products from growing mold and bacteria. There are studies that provide strong evidence that this is an endocrine disruptor.
Commonly Found In: Beauty + Personal Care (lotions, makeup, skincare, haircare products)
Pregnancy: Many people choose to limit paraben exposure during pregnancy
Source: Synthetic preservative
EWG Rating: 3-4
Methyl propanediol
Use in Moderation
An ingredient used to improve texture, increase hydration, and help other ingredients blend more evenly into the skin. It is generally considered low concern in cosmetic products, though it is a penetration enhancer and may increase the absorption of certain other harmful ingredients. It also can contribute to irritation or sensitivities in some individuals depending on the formulation and concentration used.
Commonly Found In: Beauty + Personal Care (skincare, serums, moisturizers, cosmetics)
Pregnancy: Because methyl propanediol can help certain ingredients absorb more effectively into the skin, some individuals may choose to be more selective about products that contain ingredients of concern during pregnancy.
Source: Synthetic (often corn-derived)
EWG Rating: 1
Microcrystalline Wax
Use In Moderation
A petroleum-derived wax used to thicken and improve the texture of cosmetics and personal care products. How well it is refined matters because petroleum-derived waxes can contain PAHs, a group of contaminants that includes known carcinogens. Highly refined microcrystalline wax is considered lower concern, but the quality and refining process aren't something you can tell from an ingredient label. EWG VERIFIED products that contain it have to provide additional documentation showing the ingredient meets EWG's restrictions.
Commonly Found In: Beauty + Personal Care (lip products, creams, moisturizers, makeup and skincare)
Pregnancy & Breastfeeding: Highly refined microcrystalline wax is considered lower concern. Those wanting to reduce petroleum-derived ingredients may choose plant-based wax alternatives.
Source: Petroleum-derived
EWG Rating: 1
Mineral Oil
Use in Moderation
A petroleum-derived ingredient used to create a barrier on the skin and help prevent moisture loss. How well it is refined matters because untreated or poorly refined mineral oils can contain PAHs, a group of contaminants that includes known carcinogens. Highly refined cosmetic-grade mineral oil is considered much lower concern because refining removes these impurities. Since you can't tell how well it was refined just by looking at an ingredient label, look for EWG VERIFIED products or brands that confirm they use highly refined cosmetic or pharmaceutical-grade mineral oil. EWG requires additional substantiation for mineral oil in VERIFIED products.
Commonly Found In: Beauty + Personal Care (lotions, baby oil, ointments, lip products, moisturizers and cosmetics)
Pregnancy & Breastfeeding: Highly refined cosmetic-grade mineral oil is considered lower concern. If the quality or refining process can't be verified, choosing an alternative is a simple way to limit unnecessary exposure during pregnancy and breastfeeding.
Source: Petroleum-derived
EWG Rating: 3
Mixed Tocopherols
Use in Moderation
A form of vitamin E commonly added to foods and supplements to keep oils from going rancid. Mixed tocopherols are often made from concentrated byproducts of vegetable oil refining, commonly soybean oil, so where they come from and how well they are purified matters. Research has found pesticide residues can concentrate in the raw material used to make them, although properly manufactured mixed tocopherols go through additional purification and have purity standards for contaminants.
Commonly Found In: Food & Beverage + Supplements + Beauty (protein powders, packaged snacks, nut butters, cooking oils, salad dressings, supplements, softgels and skincare)
Pregnancy & Breastfeeding: Mixed tocopherols themselves are considered lower concern. For products used regularly, look for reputable brands that test their ingredients for contaminants.
Source: Naturally derived, commonly from vegetable oils such as soybean oil
EWG Rating: N/A
Monocalcium Phosphate
Use in Moderation
A phosphate additive commonly used in baking powder and packaged foods to help foods rise and improve texture. Phosphate additives are absorbed easily by the body, so getting them from several foods regularly can add to your overall phosphorus intake. Too much phosphorus can affect the balance of calcium and other minerals in the body and put more stress on the kidneys over time. This is more of a concern with frequent exposure from multiple foods than the small amount found in one product.
Commonly Found In: Food & Beverage (baking powder, baked goods, flour products and packaged foods)
Pregnancy & Breastfeeding: Generally considered lower concern in normal food amounts
Source: Mineral-derived phosphate
EWG Rating: N/A
Monoglycerides
Use In Moderation
Processed emulsifiers used to improve the texture and shelf life of packaged foods. Some research has found that certain monoglycerides can change gut bacteria and may contribute to inflammation and changes in how the body handles blood sugar and fats. How they are made also matters. Processing oils at high temperatures can create contaminants like glycidyl esters and 3-MCPD, which have been linked to DNA damage, cancer and kidney effects in animal studies.
Commonly Found In: Food & Beverage (bread, hamburger buns, tortillas, baked goods, coffee creamers, packaged desserts, frozen foods and snack foods)
Pregnancy & Breastfeeding: Generally considered lower concern in normal food amounts, but limiting frequent exposure can help reduce overall intake of emulsifiers and processing contaminants.
Source: Made from plant oils or animal fats
EWG Rating: 1
Monopropylene Glycol
Use In Moderation
Another name for propylene glycol, an ingredient used to help products hold moisture and improve texture. It can irritate the skin, especially with frequent use or on sensitive or already irritated skin. It can also help other ingredients absorb more easily into the skin, so what else is in the product matters. The ingredient itself isn't strongly linked to cancer or reproductive harm.
Commonly Found In: Beauty + Personal Care (deodorants, lotions, moisturizers, serums, cosmetics, shaving products and hair products)
Pregnancy & Breastfeeding: Generally considered lower concern in normal cosmetic use
Source: Synthetic, commonly made from petrochemical-derived materials
EWG Rating: N/A
MSG (Monosodium Glutamate)
Use In Moderation
A flavor enhancer commonly added to packaged and restaurant foods. Some people are more sensitive to MSG and may experience headaches, flushing, nausea or tingling after eating it, especially in larger amounts. Research has also raised concerns about higher or repeated exposure and possible effects on gut health, inflammation, metabolism and brain health, although many of the more concerning findings come from animal studies using much higher amounts than we would normally get from food. Overall intake matters, especially since MSG can show up in several processed foods eaten throughout the day.
Commonly Found In: Food & Beverage (seasoning blends, flavored chips, soups, broths, frozen meals, restaurant foods, snack foods, instant noodles and packaged savory foods)
Pregnancy & Breastfeeding: Generally considered lower concern in normal food amounts. Those who notice symptoms after eating MSG may want to limit it.
Source: Fermentation-derived, typically from starch or sugars
EWG Rating: 1
Myristamide DEA
Avoid
A surfactant and foaming ingredient made from myristic acid and diethanolamine (DEA) that is used to improve lather and texture in personal care products. DEA-related ingredients may contain nitrosamine contamination depending on formulation and manufacturing methods. Nitrosamines are compounds linked to carcinogenicity concerns. It may also contribute to skin irritation or sensitivities, especially with frequent exposure.
Commonly Found In: Beauty + Personal Care (shampoos, body washes, facial cleansers, liquid soaps, and foaming personal care products)
Pregnancy: Best avoided during pregnancy due to concerns surrounding DEA-related compounds and potential nitrosamine contamination.
Source: Synthetic
EWG Rating: 1-4
N
1-Naphthol
Avoid
A chemical compound that may be used in the production of dyes, pigments, pesticides, and other industrial ingredients. It is also studied as a marker of exposure to certain pesticides and naphthalene compounds. Some research has raised concerns about possible hormone-related effects and sperm DNA damage.
Commonly Found In: Beauty + Industrial Ingredients (hair dyes, colorants, pigments, fragrance materials, pesticides, and chemical manufacturing)
Pregnancy: Best avoided when possible due to limited safety data and concerns related to hormone and reproductive health.
Source: Synthetic
EWG Rating: 5-8
Naphthalene
Avoid
A chemical used in mothballs and some industrial products that can also be released into the air from cigarette smoke and burning fuels. Naphthalene can damage red blood cells and cause anemia, particularly with higher exposures. It has also been linked to liver, neurological and eye effects. Long-term animal studies have found respiratory tumors, raising cancer concerns, although evidence in humans is limited. It can enter the body by breathing it in, swallowing it or through the skin.
Commonly Found In: Household + Industrial (mothballs, moth repellents and some industrial products); cigarette smoke and fumes from burning fuels
Pregnancy & Breastfeeding: Can cross the placenta; human safety data during pregnancy and breastfeeding is limited
Source: Petroleum and coal-derived; can also form when materials are burned
EWG Rating: 9
Nano Titanium Dioxide
Avoid
A very small particle form of titanium dioxide commonly used in sunscreens and cosmetics. The biggest concern is breathing in these tiny particles from sprays and loose powders because they can travel deep into the lungs. Research has also raised concerns about inflammation, oxidative stress, cell and DNA damage, and effects on different organs, although much of this research has been done in animals or lab studies. How concerning it is depends heavily on the size of the particles, the amount someone is exposed to and how it enters the body.
Commonly Found In: Beauty + Personal Care (mineral sunscreens, makeup, powders and some spray products)
Pregnancy & Breastfeeding: Human data is limited. Inhalation exposure from powders and sprays is the greater concern; research has not established a similar concern from applying approved nano titanium dioxide to intact skin.
Source: Mineral-derived titanium dioxide
EWG Rating: N/A
Nano Zinc Oxide
Avoid
A very small particle form of zinc oxide used mostly in mineral sunscreens and cosmetics. The biggest concern is breathing in the tiny particles from sprays and loose powders, where they can reach the lungs and cause irritation and damage. Research has also raised concerns about oxidative stress and cell damage from nanoparticle exposure, although these findings come mostly from animal and lab studies and depend on the amount and how someone is exposed.
Commonly Found In: Beauty + Personal Care (mineral sunscreens, tinted moisturizers, foundations, powders, SPF lip products, and cosmetics)
Pregnancy: Non-nano zinc oxide sunscreen is usually preferred during pregnancy. Avoid spray or powder products that may be inhaled.
Source: Synthetic mineral-derived ingredient, ultrafine particle form
EWG Rating: N/A
Natural Flavors (Unspecified)
Avoid
A broad term used for flavoring ingredients that originally come from plant, animal or other natural sources. The biggest concern is transparency because “natural flavors” doesn't tell you exactly what is in the flavor mixture. These mixtures can contain multiple flavoring ingredients along with other ingredients used to make or stabilize the flavor that may not be individually listed on the label. The word “natural” also doesn't necessarily mean the finished flavor is simple or minimally processed.
Commonly Found In: Food + Beverage (flavored drinks, sparkling waters, protein bars, snacks, cereals, yogurts, dressings, sauces, frozen meals and other packaged foods)
Pregnancy & Breastfeeding: No specific concern has been established for natural flavors as a group; the main concern is that the full flavor mixture may not be disclosed
Source: Derived from plant, animal or other natural sources but may undergo significant processing
EWG Rating: 4
Natural Fragrance
Avoid
A broad term used for fragrance made from naturally derived ingredients such as essential oils, plant extracts and other aromatic compounds. The biggest concern is that “natural fragrance” doesn't necessarily tell you what is actually in the fragrance blend. Individual fragrance ingredients may not be listed on the label, making it difficult to know what you're being exposed to. Natural fragrance ingredients can also contain known allergens and sensitizers that may cause skin irritation or allergic reactions in some people. “Natural” doesn't automatically mean a fragrance is less irritating or less likely to cause a reaction.
Commonly Found In: Household + Beauty (cleaners, laundry products, candles, air fresheners, perfumes, lotions, body washes, shampoos, deodorants and skincare)
Pregnancy & Breastfeeding: No specific concern has been established for natural fragrance as a group; the main concern is that the individual fragrance ingredients may not be fully disclosed
Source: Naturally derived fragrance ingredients; the exact composition may not be disclosed
EWG Rating: N/A
Natural Smoke Flavor / Liquid Smoke
Use in Moderation
A flavoring made by capturing smoke from burning wood and turning it into a liquid that gives foods a smoky flavor. Smoke flavorings can contain compounds that form when wood is burned, including PAHs and other chemicals that have raised concerns about DNA damage. The amount and types of these compounds can vary depending on how the smoke flavor is made and filtered.
Commonly Found In: Food + Beverage (barbecue sauces, marinades, smoked meats, jerky, bacon-flavored foods, chips, dips, canned beans and packaged savory foods)
Pregnancy & Breastfeeding: Consider limiting due to potential exposure to PAHs and other compounds in smoke flavorings that have raised concerns about DNA damage. Research specific to smoke flavorings during pregnancy is limited
Source: Made from condensed and processed wood smoke
EWG Rating: N/A
N-Hexane
Avoid
A solvent used in manufacturing and to extract oils from foods such as soybeans, peanuts and other seeds. The biggest concern with n-hexane is its effect on the nervous system. Repeated or higher exposure can damage nerves and cause numbness, tingling, weakness and problems with movement. It can also irritate the skin, eyes and lungs and has raised reproductive concerns. Exposure happens mainly from breathing it in or through skin contact.
Commonly Found In: Household + Food Processing (adhesives, rubber cement, cleaning and degreasing products and the processing of some vegetable oils and food ingredients)
Pregnancy & Breastfeeding: Consider limiting exposure. N-hexane has raised reproductive and developmental concerns.
Source: Petroleum-derived solvent
EWG Rating: N/A
Nonionic Surfactant
Avoid
A broad term for cleaning ingredients that help remove dirt, grease and oils. The biggest concern is that “nonionic surfactant” doesn't tell you which specific ingredient is actually being used. Some nonionic surfactants are ethoxylated, a manufacturing process that can leave behind 1,4-dioxane, while others are lower-concern ingredients. Without the actual ingredient name, there isn't enough information to know how it was made or fully evaluate its safety.
Commonly Found In: Household (laundry detergents, dish soaps, dishwasher detergents, all-purpose cleaners, degreasers, floor cleaners and surface sprays)
Pregnancy & Breastfeeding: The specific ingredient isn't disclosed, so there isn't enough information to fully evaluate exposure during pregnancy or breastfeeding.
Source: Varies depending on the specific surfactant
EWG Rating: N/A
Nonylphenol Ethoxylates (NPEs)
Avoid
Synthetic surfactants used to help cleaning products remove dirt, grease and oils. NPEs can break down into nonylphenol, a persistent chemical that can build up in the environment and has shown estrogen-like activity. Animal studies have also raised concerns about reproductive and developmental effects. NPEs and their breakdown products are also highly toxic to aquatic life.
Commonly Found In: Household + Industrial Products (some laundry detergents, degreasers, hard-surface cleaners, industrial cleaners, paints, coatings and textile processing)
Pregnancy & Breastfeeding: Consider avoiding due to reproductive and developmental concerns seen in animal studies and the estrogen-like activity of nonylphenol. Human pregnancy research is limited.
Source: Synthetic
EWG Rating: N/A
Nylon-12
Avoid
A synthetic ingredient used to improve texture, absorb oil, reduce shine, and create a smooth finish in cosmetics. Nylon-12 is a petroleum-derived plastic polymer that is considered a microplastic ingredient. While generally considered a lower-concern ingredient for human health, it may be best avoided in loose powder products where fine particles can become airborne and be inhaled during application. Choose products made with naturally derived alternatives to reduce unnecessary microplastic exposure.
Commonly Found In: Beauty + Personal Care (powder foundation, setting powder, blush, bronzer, eyeshadow, mascara, primers, and cosmetics)
Pregnancy: Avoid loose powders that may be inhaled and choose non-petroleum-based alternatives when possible.
Source: Synthetic, petroleum-derived plastic polymer
EWG Rating: 1
O
O-Aminophenol (2-Aminophenol)
Avoid
A synthetic chemical used in hair dyes. O-Aminophenol has shown mutagenic activity in laboratory testing, meaning it can potentially cause changes to genetic material. It can also cause skin sensitization and allergic reactions. Safety reviews found there wasn't enough evidence to establish its safe use in hair dye, and o-Aminophenol and its salts are prohibited in cosmetics in the European Union.
Commonly Found In: Beauty + Personal Care (permanent and oxidative hair dyes)
Pregnancy & Breastfeeding: Human pregnancy and breastfeeding research is limited. Because of the mutagenicity concerns and lack of adequate safety data, exposure may be worth limiting during pregnancy and breastfeeding.
Source: Synthetic
EWG Rating: 8
Octinoxate
Avoid
A chemical sunscreen ingredient that absorbs UVB rays and helps prevent sunburn. Octinoxate is absorbed through the skin and can enter the bloodstream. Research has raised concerns about endocrine activity, including possible effects on estrogen, reproductive hormones and thyroid function. It has also raised environmental concerns because it can enter waterways and affect aquatic ecosystems.
Commonly Found In: Beauty + Personal Care (sunscreens, moisturizers with SPF, lip balms, makeup and other SPF products)
Pregnancy & Breastfeeding: Human pregnancy and breastfeeding research is limited. Because octinoxate is systemically absorbed and research has raised reproductive and hormone-related concerns, limiting exposure may be considered during pregnancy and breastfeeding
Source: Synthetic
EWG Rating: 6
Octisalate
Avoid
A chemical sunscreen ingredient that absorbs UVB rays and helps prevent sunburn. Octisalate can be absorbed through the skin and enter the bloodstream. Research has raised concerns about hormone disruption, including effects on thyroid and growth hormones. Other research has raised reproductive and developmental concerns.
Commonly Found In: Beauty + Personal Care (sunscreens, moisturizers with SPF, lip balms, makeup and other SPF products)
Pregnancy & Breastfeeding: Human research during pregnancy and breastfeeding is limited. Animal studies have raised concerns about hormone, reproductive, and developmental effects
Source: Synthetic
EWG Rating: 5
Octocrylene
Avoid
A chemical sunscreen ingredient that absorbs UV rays and helps stabilize other sunscreen ingredients. One of the biggest concerns with octocrylene is that it can contain benzophenone, and research has found that the amount can increase as products age and the octocrylene breaks down. Benzophenone has raised concerns around cancer and hormone disruption. Octocrylene can also cause skin allergies or reactions in some people, especially those with sensitive skin.
Commonly Found In: Beauty + Personal Care (sunscreens, facial creams, lip products, and SPF cosmetics)
Pregnancy: Consider choosing mineral-based sunscreens containing non-nano zinc oxide when possible.
Source: Synthetic
EWG Rating: 3
Octylisothiazolinone
Avoid
A synthetic preservative used to prevent bacteria, mold, and fungi from growing in household products. Octylisothiazolinone is a well-established skin sensitizer and contact allergen, meaning repeated exposure can cause an allergy. Once sensitized, even small amounts may trigger allergic contact dermatitis. It is also highly toxic to aquatic life.
Commonly Found In: Household (cleaners, laundry products, paints, adhesives, polishes and other household products)
Pregnancy & Breastfeeding: Human research during pregnancy and breastfeeding is limited. The main concern is skin sensitization and allergic reactions
Source: Synthetic
EWG Rating: 2
Oleamide DEA
Avoid
A surfactant and emulsifier made from fatty acids and diethanolamine (DEA). DEA-related ingredients have been associated with skin irritation and may form potentially carcinogenic compounds called nitrosamines under certain manufacturing or storage conditions. Safer alternatives are widely available.
Commonly Found In: Beauty + Personal Care (shampoos, conditioners, body washes, facial cleansers, and foaming products)
Pregnancy & Breastfeeding: Because DEA-related compounds have raised concerns regarding toxicity and potential carcinogenicity, many consumers choose to avoid them during pregnancy and breastfeeding.
Source: Synthetic
EWG Rating: 1-4
Olestra
Avoid
An artificial fat substitute used to make foods lower in fat and calories. Olestra isn't digested or absorbed by the body and can interfere with the absorption of the fat-soluble vitamins A, D, E, and K. It can also cause digestive issues such as abdominal cramping, gas, loose stools, and diarrhea, especially when larger amounts are eaten.
Commonly Found In: Food (low-fat or fat-free chips, snacks, and other processed foods)
Pregnancy & Breastfeeding: Best to avoid. Olestra can reduce the absorption of fat-soluble vitamins, which are especially important during pregnancy and breastfeeding.
Source: Synthetic, made from sucrose and fatty acids derived from fats and oils
EWG Rating: N/A
Oleth-5
Avoid
An ethoxylated surfactant and emulsifier made by reacting oleyl alcohol with ethylene oxide. Because it is ethoxylated, Oleth-5 may contain residual 1,4-dioxane and ethylene oxide if manufacturers do not adequately remove these contaminants. Oleth ingredients may also increase the penetration of other ingredients through the skin. The contamination risk depends heavily on manufacturing and purification practices.
Commonly Found In: Beauty and Personal Care (cleansers, creams, lotions, hair products, and cosmetics)
Pregnancy & Breastfeeding: Avoiding ethoxylated ingredients can reduce unnecessary exposure to potential manufacturing contaminants, particularly when cleaner alternatives are available.
Source: Synthetic
EWG Rating: 1-2
Optiphen ND
Avoid
A preservative blend used to prevent bacteria, yeast, and mold from growing in personal care products. It is made mostly from phenoxyethanol, along with benzoic acid and dehydroacetic acid. Because phenoxyethanol makes up most of this blend, it carries the same concerns, including skin and eye irritation and questions about neurological and developmental effects at higher exposure levels.
Commonly Found In: Beauty and Personal Care (lotions, creams, shampoos, conditioners, cleansers, wipes, and cosmetics)
Pregnancy & Breastfeeding: Consider avoiding products preserved with Optiphen ND when phenoxyethanol-free alternatives are available, particularly in products used frequently or over large areas of the body.
Source: Synthetic
EWG Rating: N/A
Organic Natural Flavors
Moderation
Flavoring ingredients made from natural sources such as fruits, vegetables, herbs, spices, or other plant or animal sources. Organic natural flavors have stricter rules than conventional natural flavors, including restrictions on certain synthetic solvents and carriers used during processing. However, “natural flavors” can still represent a mixture of different flavoring ingredients that don't all have to be individually listed on the label, making it difficult to know exactly what is being used.
Commonly Found In: Food & Beverage (snacks, beverages, cereals, protein products, flavored waters, supplements, and packaged foods)
Pregnancy & Breastfeeding: Generally recognized as safe, but individuals with allergies or sensitivities may wish to contact the manufacturer for additional ingredient information.
Source: Naturally derived (from plants or animals, but processed)
EWG Rating: N/A
Oxalic Acid
Avoid
An acid that occurs naturally in some foods but is also used in concentrated form in household cleaners. Concentrated oxalic acid can cause serious skin and eye burns and can irritate the respiratory system if inhaled. If swallowed in larger amounts, it can bind to calcium in the body and form calcium oxalate crystals, which can damage the kidneys.
Commonly Found In: Household (rust removers, wood cleaners, metal cleaners, deck cleaners, and stain removers)
Pregnancy & Breastfeeding: Avoid unnecessary exposure to concentrated oxalic acid cleaners. Wear gloves, ensure good ventilation, and choose safer alternatives when available.
Source: Naturally derived (from plants) or manufactured synthetically for industrial use
EWG Rating: N/A
Oxybenzone
Avoid
A chemical sunscreen ingredient that absorbs UV rays and helps prevent sunburn. Oxybenzone is readily absorbed through the skin and has been detected in the body after sunscreen use. Research has raised concerns about hormone disruption and possible reproductive and developmental effects. It can also cause allergic skin reactions in some people and has raised environmental concerns because of its effects on marine life.
Commonly Found In: Beauty (chemical sunscreens, SPF moisturizers, lip balms, foundations, and lotions)
Pregnancy & Breastfeeding: Because oxybenzone is absorbed systemically and its long-term safety is still debated, many healthcare providers recommend mineral sunscreens with non-nano zinc oxide or non-nano titanium dioxide during pregnancy and breastfeeding.
Source: Synthetic
EWG Rating: 4
P
p-Aminophenol (4-Aminophenol)
Avoid
A synthetic dye used mainly in permanent hair color. It is a known skin sensitizer and can cause allergic reactions, especially with repeated exposure. Animal and laboratory studies have also found kidney toxicity and cellular damage at higher levels of exposure.
Commonly Found In: Beauty (permanent and oxidative hair dyes)
Pregnancy & Breastfeeding: Avoid when possible. There isn't strong evidence of reproductive or developmental toxicity, but it is still a sensitizing hair-dye chemical with other health concerns.
Source: Synthetic (coal-tar-derived hair dye)
EWG Rating: 7
(Refined) Palm Oil / Palm Olein
Avoid
Palm oil that has been industrially refined at high temperatures to remove unwanted colors, odors and flavors. This high-temperature processing can create contaminants called 3-MCPD esters and glycidyl esters, with some of the highest levels found in refined palm oil and palm olein. Glycidyl esters can break down during digestion into glycidol, which can damage DNA and has caused cancer in animal studies. 3-MCPD has also been linked to kidney and male reproductive effects in animal studies. These contaminants come from the refining process and are not the same concern with unrefined, virgin or cold-pressed palm oil.
Commonly Found In: Food + Beverage (baked goods, crackers, snack foods, chocolate spreads, margarine, shortening, processed foods and refined cooking oils)
Pregnancy & Breastfeeding: Refined palm oil is commonly used in foods, including some infant formulas. Exposure to 3-MCPD and glycidyl esters depends on the amount present in the refined oil and how much is consumed.
Source: Naturally derived palm oil that has been industrially refined
EWG Rating: N/A
Papain
Use In Moderation
A digestive enzyme naturally derived from papaya that helps break down proteins. It is commonly used in digestive supplements and as a meat tenderizer. Papain is generally well tolerated, but it can cause allergic reactions, especially in people with papaya or latex allergies. Inhaled papain powder can also cause respiratory sensitization and allergic reactions, making exposure to powdered forms more of a concern.
Commonly Found In: Supplements (digestive enzyme blends, gut health supplements and digestive tablets); Food + Beverage (meat tenderizers and some processed meat products)
Pregnancy & Breastfeeding: Safety data on supplemental papain during pregnancy and breastfeeding are limited. Concerns about papaya during pregnancy mainly involve papaya latex and unripe papaya, so they should not automatically be applied to small amounts of purified papain in supplements.
Source: Naturally derived (papaya)
EWG Rating: 1-2
Paraffinum Liquidum (Mineral Oil)
Avoid (Untreated or Poorly Refined)
A petroleum-derived oil used to soften skin and prevent moisture loss. It may also show up on labels as mineral oil, liquid paraffin, paraffin oil, liquid petrolatum, white mineral oil, or white oil. The concern is with mineral oil that hasn't been properly refined, which can contain MOAH, including PAHs that are known to cause cancer. Highly refined cosmetic-, pharmaceutical-, and food-grade mineral oils are purified to significantly reduce these contaminants. The problem is that an ingredient list usually doesn't tell you how well the mineral oil was refined or whether it was tested for these contaminants. For products that may come into contact with food, like cutting-board oil, look specifically for food-grade white mineral oil or USP-grade mineral oil.
Commonly Found In: Beauty + Personal Care (lotions, creams, ointments, baby oil, lip products); Household (cutting-board oils, lubricants)
Pregnancy & Breastfeeding: Highly refined mineral oil is considered low concern for topical use; the concern is with untreated or inadequately refined mineral oil
Source: Synthetic (petroleum-derived)
EWG Rating: 3
Parfum (Fragrance)
Avoid (Undisclosed Blend)
A blanket term used for a mixture of fragrance ingredients that may appear on a label as fragrance, parfum, perfume, or aroma. The individual ingredients don't always have to be disclosed, making it difficult to know exactly what's in the fragrance or evaluate it as a whole. Depending on the formula, fragrance blends can contain known allergens and sensitizers, solvents, phthalates, synthetic musks, and other fragrance chemicals, some of which have raised concerns around skin and respiratory irritation, hormone disruption, and reproductive effects. This doesn't mean every fragrance ingredient carries these concerns; the issue is that fragrance or parfum alone doesn't tell you which ingredients are actually being used.
Commonly Found In: Beauty & Personal Care (perfume, body wash, shampoo, conditioner, facial cleanser, moisturizer, serum, deodorant, lotion, makeup, hair styling products, lip products, and shaving cream); Household (laundry detergent, fabric softener, dryer sheets, dish soap, all-purpose cleaners, candles, wax melts, air fresheners, room sprays, carpet deodorizers, and toilet bowl cleaners)
Pregnancy & Breastfeeding: The individual ingredients in a fragrance blend may not be disclosed, making it difficult to evaluate pregnancy and breastfeeding safety as a whole
Source: Synthetic or naturally derived (various sources)
EWG Rating: 8
PCA Dimethicone
Use In Moderation
A silicone-derived conditioning ingredient used to smooth skin and hair and help hold in moisture. PCA Dimethicone itself is considered low concern for direct toxicity, but silicone manufacturing can leave behind small amounts of cyclic siloxanes such as D4 and D5. These impurities have raised reproductive, endocrine, and environmental concerns, although the amount remaining in a finished product depends on how the ingredient was manufactured and purified.
Commonly Found In: Beauty & Personal Care (conditioners, hair serums, anti-frizz products, moisturizers, face primers, foundations, concealers, BB creams, sunscreens, and anti-aging skincare)
Pregnancy & Breastfeeding: No pregnancy-specific concerns have been established for PCA Dimethicone itself; potential D4/D5 impurities depend on manufacturing and purification
Source: Synthetic (silicone-derived)
EWG Rating: 1-2
Peanut Oil (Refined)
Use In Moderation
An oil made from peanuts that may also appear on labels as Arachis Hypogaea (Peanut) Oil or arachis oil. When used in food, high-temperature refining can create 3-MCPD esters, and repeated high-heat frying can cause the oil to oxidize and form additional breakdown products. In skincare, refined peanut oil is considered low concern for direct toxicity, but it can increase the skin's absorption of other ingredients in a formula. Refining also removes most of the peanut proteins responsible for allergic reactions, although the amount remaining depends on how thoroughly the oil was refined.
Commonly Found In: Food & Beverage (cooking oils, restaurant fried foods, sauces, dressings, baked goods, and processed snack foods); Beauty & Personal Care (lotions, creams, body oils, hair products, and some medicated skincare)
Pregnancy & Breastfeeding: No specific concerns have been established for normal dietary or topical use during pregnancy or breastfeeding
Source: Naturally derived (from peanuts)
EWG Rating: 1-4
Peanut Oil (Hydrogenated)
Avoid (Partially Hydrogenated)
Peanut oil that has been chemically changed through hydrogenation to make it more solid and shelf-stable. The important difference is whether it is partially or fully hydrogenated. Partially hydrogenated peanut oil contains artificial trans fats, which raise LDL ("bad") cholesterol and increase the risk of heart disease. Fully hydrogenated peanut oil contains little to no trans fat and doesn't carry the same concern. Partially hydrogenated oils have been removed from most foods sold in the U.S., but may still be encountered in some foods made outside the U.S.
Commonly Found In: Food & Beverage (older or imported packaged baked goods, cookies, crackers, shortening, margarine, frostings, snack foods, and other processed foods)
Pregnancy & Breastfeeding: No specific concern has been established for peanut oil itself during pregnancy or breastfeeding; industrial trans fats from partially hydrogenated oils should be kept as low as possible
Source: Chemically modified peanut oil
EWG Rating: 1
Phenoxyethanol
Avoid
A synthetic preservative used to prevent bacteria, yeast, and mold from growing in water-based products. Phenoxyethanol can be absorbed through the skin, although the body also breaks it down and eliminates it fairly quickly. Research at higher exposure levels has found effects on the nervous system, and repeated exposure can lead to headaches, numbness, weakness, and cognitive symptoms. Animal studies have also found systemic and reproductive effects at much higher exposures than what would typically come from cosmetics. Regulatory agencies currently consider phenoxyethanol safe in cosmetics at concentrations up to 1%, but these safety assessments don't account for exposure from non-cosmetic sources.
Commonly Found In: Beauty & Personal Care (moisturizers, serums, lotions, sunscreens, cleansers, shampoos, conditioners, baby wipes, foundations, cosmetics, and liquid soaps)
Pregnancy & Breastfeeding: Human research during pregnancy and breastfeeding is limited. Animal studies found reproductive and developmental effects at higher exposures, but these effects have not been established from normal cosmetic use
Source: Synthetic
EWG Rating: 2-4
Phenol
Avoid
A chemical used in some disinfectants, medical treatments, chemical peels, and industrial products. Phenol can be quickly absorbed through the skin, and concentrated amounts can cause serious skin and eye burns. Higher exposures can also affect the nervous system and kidneys. Animal studies have found developmental effects at higher amounts.
Commonly Found In: Beauty & Personal Care (chemical peels, antiseptic products); Household (industrial cleaners, disinfectants)
Pregnancy & Breastfeeding: Because phenol can be absorbed through the skin and high exposures have been associated with developmental toxicity in animal studies, unnecessary exposure is best avoided during pregnancy.
Source: Synthetic
EWG Rating: N/A
PEGs (Polyethylene Glycol, PEG-8, PEG-40, PEG-100, PEG-120, etc.)
Avoid
A large group of synthetic ingredients used to thicken products, improve texture, and help ingredients mix together. PEGs themselves are considered fairly low in toxicity, but the manufacturing process can leave behind 1,4-dioxane and ethylene oxide, two contaminants linked to cancer. These contaminants can be significantly reduced with proper purification, but there's no way to tell from an ingredient label how well a PEG was purified or tested. PEGs are usually easy to spot on a label because you'll see PEG followed by a number in the ingredient name.
Commonly Found In: Beauty & Personal Care (cleansers, shampoos, lotions, creams, sunscreens, makeup, toothpaste)
Pregnancy & Breastfeeding: Because PEGs may contain trace amounts of 1,4-dioxane and ethylene oxide from manufacturing, many women choose to limit unnecessary exposure during pregnancy and breastfeeding.
Source: Synthetic (petroleum-derived)
EWG Rating: 1-2
PEG-12 Dimethicone
Avoid
A silicone-based ingredient used to make products feel smoother, spread more easily, and help hold in moisture. PEG-12 Dimethicone itself is considered fairly low in toxicity, but the manufacturing process can leave behind contaminants like 1,4-dioxane, ethylene oxide, D4, and D5. These contaminants can be reduced with proper manufacturing and purification, but there's no way to tell from an ingredient label how well it was purified or tested.
Commonly Found In: Beauty & Personal Care (foundations, primers, moisturizers, sunscreens, hair products)
Pregnancy & Breastfeeding: Although no pregnancy-specific risks have been established, some women choose to avoid ethoxylated ingredients because they may contain trace manufacturing impurities.
Source: Synthetic (silicone and petroleum-derived PEG)
EWG Rating: 1-2
PEI-14 PEG-24/PPG-16 Copolymer
Avoid
A synthetic conditioning and film-forming ingredient used to improve texture and product performance. Because it contains PEG and PPG compounds, it is produced through ethoxylation, a process that may leave behind trace amounts of 1,4-dioxane if not properly purified. Some people with sensitive skin may also experience irritation.
Commonly Found In: Beauty & Personal Care (hair products, conditioners, styling products, cosmetics)
Pregnancy & Breastfeeding: Because this ingredient is produced through ethoxylation, some women choose to limit unnecessary exposure due to the potential for trace manufacturing impurities
Source: Synthetic
EWG Rating: N/A
Pentylene Glycol
Use In Moderation
A synthetic ingredient used to help products hold onto moisture, improve texture, and boost preservatives. It's generally considered low in toxicity, but it can cause irritation or allergic contact dermatitis in some people, especially those with sensitive or already irritated skin. It can also increase the skin's absorption of other ingredients in a formula, which may be more of a concern depending on what those ingredients are.
Commonly Found In: Beauty & Personal Care (serums, moisturizers, sunscreens, cleansers, cosmetics)
Pregnancy & Breastfeeding: No evidence currently suggests this ingredient poses a concern during pregnancy or breastfeeding when used in cosmetics.
Source: Synthetic (can also be plant-derived)
EWG Rating: 2
Peppermint Oil (Mentha × piperita Oil)
Use In Moderation
An essential oil made from peppermint that's commonly used for its cooling effect and minty scent. Peppermint oil can irritate the skin or cause an allergic reaction in some people, especially when it's used undiluted or at higher concentrations. Independent testing has also found phthalate contamination in some peppermint essential oils. Phthalates aren't naturally part of peppermint oil, so this is a product purity and sourcing issue rather than a concern with peppermint itself.
Commonly Found In: Beauty & Personal Care (lip balms, toothpaste, lotions, shampoos, essential oil blends)
Pregnancy & Breastfeeding: Pregnancy-specific safety research is limited. Concentrated essential oils should be used with caution and peppermint oil should not be applied to the nipple before nursing
Source: Naturally Derived (peppermint plant)
EWG Rating: 1
Perchloroethylene (Tetrachloroethylene, PERC)
Avoid
A synthetic solvent best known for its use in dry cleaning, but it's also found in some cleaners, degreasers, adhesives, and other products. PERC can be breathed in or absorbed through the skin, and repeated or higher exposure has been linked to nervous system effects and damage to the kidneys and liver. Long-term exposure has also been linked to an increased risk of cancer.
Commonly Found In: Household (dry-cleaning chemicals, carpet spot removers, industrial degreasers)
Pregnancy & Breastfeeding: Avoid exposure whenever possible, as prolonged exposure has been associated with developmental concerns and pregnancy complications.
Source: Synthetic
EWG Rating: N/A
Permethrin
Avoid
A synthetic insecticide used in bug sprays, insect-treated clothing, and treatments for lice and scabies. Permethrin works by affecting the nervous system, with neurological effects seen at higher exposures. Animal studies have also raised concerns about cancer, although research in humans has not shown a clear link. Permethrin is also highly toxic to aquatic life and bees.
Commonly Found In: Household (insect sprays, treated clothing, outdoor gear); Personal Care (lice treatments)
Pregnancy & Breastfeeding: Research on repeated pesticide exposure during pregnancy has raised developmental concerns, and permethrin has been detected in human breast milk after environmental exposure, although the amounts measured have generally been below established safety limits. Short-term topical treatment for lice or scabies has low absorption and is considered low risk when medically needed.
Source: Synthetic
EWG Rating: N/A
Perfluorooctanoic Acid (PFOA)
Avoid
A man-made PFAS, often called a “forever chemical,” that has been used in the manufacturing of non-stick, stain-resistant, grease-resistant, and water-resistant products. PFOA breaks down extremely slowly, allowing it to build up in the environment and remain in the body for years. Human studies have associated higher exposure with kidney and testicular cancer, increased cholesterol, changes in liver function, reduced immune response, and pregnancy-related effects.
PFOA may not appear on an ingredient label, but exposure can still occur through contaminated drinking water, food, household dust, environmental contamination, and some products or materials containing PFAS.
Commonly Found In/Exposure: Contaminated drinking water and food, household dust, PFAS-contaminated areas, and some non-stick, stain-resistant, grease-resistant, or water-resistant products and materials
Pregnancy & Breastfeeding: PFOA can cross the placenta and has been detected in breast milk. Higher exposure during pregnancy has been associated with pregnancy-related and developmental effects.
Source: Synthetic
EWG Rating: N/A
Phenethyl Alcohol (Benzene ethanol)
Avoid
A fragrance ingredient and preservative used in personal care products for its rose-like scent and to help prevent bacteria from growing. It can irritate the skin, eyes, and airways and may cause allergic skin reactions in some people. Studies during pregnancy have also found smaller babies, changes in bone development, pregnancy loss, and birth defects at higher exposures.
Commonly Found In: Beauty + Personal Care (perfumes, lotions, creams, soaps, shampoos, skincare, and fragranced products)
Pregnancy & Breastfeeding: Animal studies during pregnancy have found pregnancy loss, smaller babies, and changes in development at higher exposures.
Source: Synthetic or naturally occurring
EWG Rating: 2
Phosphoric Acid
Use In Moderation
An acid used to adjust pH in cosmetics and add acidity to foods and beverages. In cosmetics, the small amounts used to balance pH are generally considered low concern. The bigger consideration is frequent dietary exposure to added phosphates, which are easily absorbed and can contribute significantly to overall phosphorus intake. Very high phosphate intake can place additional stress on the kidneys, particularly in people with reduced kidney function. Concentrated phosphoric acid can also irritate or burn the skin and eyes, but this isn't representative of the diluted amounts used in finished products.
Commonly Found In: Food & Beverage (colas, some processed foods & beverages); Beauty & Personal Care (hair products, cleansers & cosmetics)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified at typical food or cosmetic exposure levels
Source: Synthetic
EWG Rating: 1
Phthalates (DEP, DBP, DEHP, BBP, DiNP, DiDP, DnHP)
Avoid
A group of synthetic chemicals used to make plastics more flexible and as solvents or stabilizers in fragrances and other products. Not all phthalates have the same health concerns, but several have been linked to reproductive and developmental effects. Human research has found stronger evidence for DEHP and DBP, including associations with changes in reproductive hormones, semen quality, fertility, and male reproductive development. Some phthalates have also been associated with an increased risk of preterm birth.
Phthalates aren't always easy to identify on a label. Some may be listed by name, while those used as part of a fragrance mixture may be hidden under “Fragrance” or “Parfum.”
Commonly Found In: Beauty & Personal Care (fragrances, nail products, hair products & some cosmetics); Household (vinyl flooring, shower curtains, plastic products, adhesives, paints, coatings & some fragranced products); Food & Beverage (food contact materials and food contamination)
Pregnancy & Breastfeeding: Prenatal exposure to some phthalates has been associated with reproductive and developmental effects and an increased risk of preterm birth, although the strength of the evidence varies by phthalate.
Source: Synthetic
EWG Rating: 10
Phthalimidoperoxycaproic Acid (PAP)
Use In Moderation
A synthetic bleaching agent used as a peroxide-free alternative in teeth whitening products. Research on PAP is still limited, especially when it comes to repeated and long-term exposure. One laboratory study found that direct PAP exposure reduced the viability of human oral cells, raising concerns about contact with the gums and other soft tissues. Because PAP is used directly in the mouth, concentration, formulation, and frequency of use are important to consider.
Commonly Found In: Beauty & Personal Care (teeth whitening strips, gels, pens & some whitening toothpastes)
Pregnancy & Breastfeeding: PAP-specific safety research during pregnancy and breastfeeding is limited
Source: Synthetic
EWG Rating: 1
Poloxamer 184
Avoid
A synthetic cleansing ingredient used to help remove oil and dirt. Poloxamer 184 itself is considered fairly low in toxicity, but the way it's made can leave behind contaminants like 1,4-dioxane, ethylene oxide, and propylene oxide. These contaminants are concerning because they have been linked to cancer in human or animal research. How much, if any, remains depends on how the ingredient is made and purified.
Commonly Found In: Beauty & Personal Care (micellar waters, makeup removers, facial cleansers, eye makeup removers, conditioners & hair products)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified for Poloxamer 184 itself. The primary concern is potential manufacturing contaminants
Source: Synthetic
EWG Rating: 2-3
Poloxamer 407
Avoid
A synthetic ingredient used to help ingredients mix together and improve the texture of a product. Poloxamer 407 itself is considered fairly low in toxicity, but the way it's made can leave behind contaminants like 1,4-dioxane, ethylene oxide, and propylene oxide if they aren't properly removed. 1,4-dioxane and ethylene oxide are linked to cancer, while propylene oxide has caused cancer in animal studies. How much, if any, is left behind depends on how the ingredient is made and purified.
Commonly Found In: Beauty & Personal Care (cleansers, micellar water, toothpaste, contact lens solutions, cosmetics)
Pregnancy & Breastfeeding: Because it is an ethoxylated ingredient, some women choose to limit unnecessary exposure during pregnancy due to the potential for trace manufacturing impurities.
Source: Synthetic
EWG Rating: 2
Polyacrylamide
Avoid
A synthetic ingredient used to thicken products and improve texture. Polyacrylamide itself is considered fairly low in toxicity, but the way it's made can leave behind acrylamide. Acrylamide is concerning because it can damage the nervous system and has caused cancer and reproductive effects in animal studies. How much, if any, remains depends on manufacturing and purification.
Commonly Found In: Beauty & Personal Care (moisturizers, anti-aging creams, facial masks, serums, makeup & hair styling products)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified for Polyacrylamide itself. The main concern is potential acrylamide contamination.
Source: Synthetic
EWG Rating: 2-6
Polyaminopropyl Biguanide (Polyhexamethylene Biguanide, PHMB)
Avoid
A synthetic preservative and antimicrobial used to prevent bacteria from growing in products. PHMB can irritate the skin and respiratory system and may cause allergic reactions. Animal studies have also found liver tumors with long-term exposure, although it's unclear how relevant those findings are to humans. There is also limited safety information on breathing it in, making spray products a greater concern.
Commonly Found In: Beauty & Personal Care (moist wipes, cleansers, cosmetics, personal lubricants, contact lens solutions)
Pregnancy & Breastfeeding: Because of concerns about long-term toxicity and limited safety data during pregnancy, many women choose to avoid products containing PHMB.
Source: Synthetic
EWG Rating: 4
Polybrominated Diphenyl Ethers (PBDEs)
Avoid
A group of synthetic flame-retardant chemicals that were widely used in furniture, mattresses, electronics, and other household products. PBDEs can escape from products, collect in household dust, and build up in the body. Human research has linked PBDE exposure to effects on brain development and thyroid hormones, and a large U.S. study found that higher levels of PBDEs in the blood were associated with an increased risk of dying from cancer.
Commonly Found In: Household (older upholstered furniture, foam cushions, mattresses, electronics, carpeting, vehicle interiors & textiles)
Pregnancy & Breastfeeding: PBDEs can cross the placenta and have been detected in breast milk. Exposure during pregnancy is a concern because of research linking developmental exposure to effects on children's brain development
Source: Synthetic (brominated flame retardants)
EWG Rating: N/A
Polyethylene
Avoid
A petroleum-derived plastic used to improve texture, bind ingredients, or form a film on the skin. Polyethylene itself is considered fairly low in toxicity, but the bigger concern is microplastics. Polyethylene can exist as or break down into tiny plastic particles that persist in the environment and have been found in human tissues. Research is still developing, but animal and laboratory studies have raised concerns about inflammation, cellular damage, and reproductive and developmental effects.
Commonly Found In: Beauty & Personal Care (makeup, lipstick, mascara, creams, cleansers, exfoliating products & hair products)
Pregnancy & Breastfeeding: Polyethylene microplastics have been found in human placentas and breast milk. Animal studies have also raised concerns about reproductive and developmental effects, although it's not yet known what these findings mean for typical human exposure
Source: Synthetic (from petroleum)
EWG Rating: 1
Polyethylene Glycol (PEG)
Avoid
A group of synthetic ingredients usually listed as PEG followed by a number, such as PEG-8 or PEG-40. PEGs themselves are considered fairly low in toxicity, but the way they're made can leave behind 1,4-dioxane and ethylene oxide if they aren't properly purified. These contaminants are concerning because 1,4-dioxane and ethylene oxide is linked to cancer. How much, if any, remains depends on how the ingredient is made and purified.
Commonly Found In: Beauty, Personal Care & Household (moisturizers, creams, cleansers, shampoos, conditioners, body washes, makeup, detergents & cleaning products)
Pregnancy & Breastfeeding: Because manufacturing contaminants cannot be identified from a product label, many women choose to limit PEG-containing products during pregnancy and breastfeeding.
Source: Synthetic (commonly petroleum-derived and ethoxylated)
EWG Rating: 1-2
Polyethyleneimines Alkoxylated
Avoid
A group of synthetic ingredients used to help detergents clean better and keep dirt from sticking back onto fabrics. They can irritate the skin and eyes and are made through a process called alkoxylation, which can leave behind 1,4-dioxane and ethylene oxide if they aren't properly removed. Both are linked to cancer. How much, if any, remains depends on how the ingredient is made and purified.
Commonly Found In: Household (laundry detergents, stain removers & other cleaning products)
Pregnancy & Breastfeeding: There isn't enough pregnancy-specific research on these ingredients. The main concerns are irritation and potential manufacturing contaminants
Source: Synthetic (often petroleum-derived and alkoxylated)
EWG Rating: N/A
Polyoxymethylene Urea
Avoid
A synthetic ingredient made from urea and formaldehyde and used to improve texture and help products last longer. It can contain or release formaldehyde, which is linked to cancer and can cause skin allergies and irritation. Inhalation is an additional concern because breathing in the powder can expose the lungs directly, and animal studies found lung inflammation with repeated inhalation.
Commonly Found In: Beauty & Personal Care (face powder, setting powder, blush, foundation & some creams)
Pregnancy & Breastfeeding: Because this ingredient may contain residual formaldehyde, many people choose to limit unnecessary exposure during pregnancy and while breastfeeding.
Source: Synthetic
EWG Rating: 8
Polytetrafluoroethylene (PTFE, Teflon)
Avoid
A synthetic PFAS used to create nonstick, stain-resistant, and water-resistant surfaces. PTFE itself is fairly stable at normal temperatures, but high heat can cause it to break down and release fumes that can cause flu-like symptoms known as polymer fume fever. PTFE is also extremely persistent in the environment and is part of the larger PFAS family of “forever chemicals.”
Commonly Found In: Household & Personal Care (nonstick cookware, bakeware, air-fryer baskets, waffle makers, stain-resistant materials, some dental floss & some cosmetics)
Pregnancy & Breastfeeding: Pregnancy-specific research on PTFE itself is limited. Avoiding inhalation of fumes from overheated PTFE is especially important
Source: Synthetic
EWG Rating: 10
Polyquaternium-7
Avoid
A synthetic ingredient used to make hair and skin feel softer and smoother. Polyquaternium-7 itself is considered fairly low in toxicity, but the way it's made can leave behind acrylamide. Acrylamide is concerning because it can damage the nervous system and has been linked to cancer and reproductive effects. How much, if any, remains depends on how the ingredient is made and purified.
Commonly Found In: Beauty & Personal Care (shampoos, conditioners, hair styling products, body washes & lotions)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified for Polyquaternium-7 itself. The main concern is potential acrylamide contamination.
Source: Synthetic
EWG Rating: 1-5
Polysorbate 20
Avoid
An emulsifier used to help ingredients mix together. Laboratory studies using human intestinal cells suggest it can affect the gut lining and trigger inflammation. The way it's made can also leave behind 1,4-dioxane and ethylene oxide if they aren't properly removed. Both are linked to cancer.
Commonly Found In: Beauty & Personal Care (cleansers, moisturizers, shampoos, conditioners, makeup, sprays, baby products & some lip and oral-care products)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified for Polysorbate 20 itself. The main concern is potential manufacturing contaminants
Source: Synthetic (ethoxylated ingredient)
EWG Rating: 2
Polysorbate 40
Avoid
An emulsifier used to help ingredients mix together. Polysorbate 40 itself is considered fairly low in toxicity, but the way it's made can leave behind 1,4-dioxane and ethylene oxide if they aren't properly removed. Both are linked to cancer.
Commonly Found In: Beauty & Personal Care (moisturizers, creams, cleansers, hair products & makeup)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified for Polysorbate 40 itself. The main concern is potential manufacturing contaminants
Source: Synthetic (Ethoxylated)
EWG Rating: 1-2
Polysorbate 60
Avoid
An emulsifier used to help ingredients mix together. Animal and lab studies suggest it may affect the gut lining and increase intestinal permeability. The way it's made can also leave behind 1,4-dioxane and ethylene oxide if they aren't properly removed. Both are linked to cancer.
Commonly Found In: Beauty & Personal Care (moisturizers, creams, makeup, conditioners, sunscreens, baby products & some lip products); Food (baked goods, desserts, sauces & processed foods)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been identified for Polysorbate 60 itself. The main concern is potential manufacturing contaminants
Source: Synthetic (ethoxylated ingredient)
EWG Rating: 2
Polysorbate 80
Avoid
An emulsifier used to help ingredients mix together. Animal and laboratory studies suggest it can disrupt the gut microbiome, affect the intestinal lining, and promote inflammation. It has also been linked to rare hypersensitivity reactions. The way it's made can leave behind 1,4-dioxane and ethylene oxide if they aren't properly removed. Both are linked to cancer.
Commonly Found In: Food & Beverage + Beauty + Medical Products (ice cream, processed foods, supplements, skincare, pharmaceuticals, some vaccine formulations)
Pregnancy: Some individuals may prefer to avoid unnecessary cumulative exposure to ethoxylated ingredients during pregnancy due to contamination concerns.
Source: Synthetic (ethoxylated ingredient)
EWG Rating: 2
Polyurethane Foam
Avoid
A synthetic foam commonly used in mattresses, couches, cushions, car seats, and insulation. Chemicals used to make polyurethane can irritate the lungs and trigger asthma, especially during manufacturing or when spray foam is being installed. Some polyurethane foam is also treated with flame retardants linked to hormone, reproductive, developmental, neurological, and cancer concerns. These chemicals can come out of the foam, collect in household dust, and increase everyday exposure.
Commonly Found In: Household (mattresses, couches, upholstered furniture, cushions, carpet padding & insulation); Baby + Kids (some car seats, nursing products & padded products)
Pregnancy & Breastfeeding: Concerns depend largely on the chemicals used to manufacture or treat the foam, particularly certain flame retardants.
Source: Synthetic (Petroleum-derived)
EWG Rating: N/A
Potassium Benzoate
Use In Moderation
A preservative used to help prevent mold and bacteria in food and personal care products. It can trigger hypersensitivity reactions in some people. When it's combined with vitamin C in certain drinks, it can also form benzene, a chemical linked to cancer. Higher temperatures and longer storage can increase how much benzene forms.
Commonly Found In: Food + Beverage (soft drinks, juices, flavored drinks, sauces, condiments & packaged foods); Beauty & Personal Care (skincare, makeup & personal care products)
Pregnancy & Breastfeeding: Human research is limited, but animal studies using dietary exposure have not found reproductive or developmental effects, even at much higher amounts than typical human exposure
Source: Synthetic
EWG Rating: 1
Potassium Bromate (Bromated Flour)
Avoid
A chemical added to flour to strengthen dough and help baked goods rise. Potassium bromate has been linked to kidney and thyroid tumors in animal studies and can damage DNA. It is considered a possible human carcinogen and has been banned as a flour additive in many countries, although it is still allowed in foods in much of the U.S.
Commonly Found In: Food (bromated flour, breads, rolls, pizza dough, pastries & other baked goods)
Pregnancy & Breastfeeding: Best to avoid due to its potential cancer and DNA-damaging effects.
Source: Synthetic
EWG Rating: N/A
Potassium Hydroxide (Lye)
Use In Moderation
A chemical used to adjust pH and help make soaps. In properly formulated products, small amounts are generally considered low concern. In concentrated form it is highly corrosive and can cause serious skin and eye burns. Breathing in potassium hydroxide dust, mist, or spray can also irritate and damage the respiratory tract, making inhalable products a greater concern.
Commonly Found In: Beauty + Personal Care (soaps, cleansers, shaving products & some hair products); Household (oven and grill cleaners, drain cleaners, heavy-duty degreasers & some concentrated cleaners)
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concerns have been identified from properly formulated cosmetic products. The greatest risk comes from concentrated potassium hydroxide before it has been diluted or fully reacted during manufacturing.
Source: Synthetic
EWG Rating: 2-5
Potassium Nitrate
Use In Moderation
A nitrate salt commonly used in toothpaste for sensitive teeth and in some foods. High nitrate exposure can interfere with how the thyroid uses iodine and can affect the blood's ability to carry oxygen after nitrate is converted to nitrite in the body. Animal studies have also found reproductive and developmental effects at high exposures. These concerns are mainly associated with higher systemic exposure rather than the small amount used in toothpaste that isn't swallowed.
Commonly Found In: Beauty + Personal Care (sensitive-teeth toothpaste); Food + Beverage (some cured meats, preserved meats, cheeses & processed fish); Other (fertilizers & some industrial products)
Pregnancy & Breastfeeding: Animal studies have found reproductive and developmental effects at high exposures
Source: Synthetic
EWG Rating: 1
Potassium Sorbate
Use In Moderation
A preservative used to prevent the growth of mold, yeast, and fungi in foods, beverages, supplements, and personal care products. It is generally considered safe at the levels used in consumer products. However, some people may experience skin irritation or allergic reactions, particularly with repeated exposure. Laboratory studies have also raised questions about oxidative stress and DNA damage under certain conditions (reacting with vitamin C and iron ).
Commonly Found In: Food & Beverage, Beauty, Supplements
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concerns have been identified from normal use. However, long-term research on repeated exposure is limited.
Source: Synthetic
EWG Rating: 2
PPG-26
Avoid
A synthetic ingredient used to improve texture, stabilize products, and help other ingredients dissolve. It is made through a manufacturing process called ethoxylation, which can leave behind small amounts of 1,4-dioxane and ethylene oxide if the ingredient is not properly purified. Both are considered potential carcinogens, making contamination the primary concern rather than the ingredient itself.
Commonly Found In: Beauty (Moisturizers, Creams, Makeup), Household (Cleaning Products)
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concerns have been identified from the ingredient itself. However, potential contamination with 1,4-dioxane and ethylene oxide may be a consideration, particularly during pregnancy.
Source: Synthetic (Ethoxylated, Petroleum-derived)
EWG Rating: N/A
Propanediol
Use In Moderation
A moisturizing ingredient and solvent used to help products hold onto moisture, improve texture, and help other ingredients dissolve. Propanediol itself is generally considered lower concern, but it can help other ingredients absorb more easily through the skin, which means what else is in the formula matters. It can also cause irritation or sensitivity in some people, especially with frequent use or sensitive skin.
Commonly Found In: Beauty + Personal Care (moisturizers, serums, cleansers, deodorants, makeup, haircare, and other skincare products)
Pregnancy & Breastfeeding: Generally considered lower concern in normal topical use. What else is in the formula matters because Propanediol can increase the absorption of other ingredients through the skin.
Source: Synthetic or plant-derived, often made through fermentation
EWG Rating: 2
Propiconazole
Avoid
A synthetic fungicide used on many conventional crops, including mushrooms, corn, rice, peanuts, almonds, oats, peaches, bananas, and other fruits. The U.S. Environmental Protection Agency has classified propiconazole as a possible human carcinogen based on animal studies. Research has also linked long-term exposure to liver damage, hormone disruption, and reproductive and developmental effects in animals. While food residues are regulated, small amounts may remain on conventionally grown produce.
Commonly Found In: Food (Conventional Produce and Grains)
Pregnancy & Breastfeeding: Animal studies have found reproductive and developmental effects at certain exposure levels. Human research is limited, but reducing unnecessary exposure during pregnancy may be especially important.
Source: Synthetic
EWG Rating: N/A
Propylene Glycol
Use In Moderation
AA synthetic ingredient used to help products hold moisture, improve texture, and help other ingredients absorb into the skin. It can irritate the skin and cause allergic contact dermatitis in some people. It can also increase how easily other ingredients penetrate the skin, which may increase exposure to whatever it's used with.
Commonly Found In: Beauty (Moisturizers, Lotions, Serums, Makeup, Deodorants), Household (Cleaning Products), Food & Beverage, Medications
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concerns have been identified from normal cosmetic use. Skin irritation is the primary concern, and products should be used as directed.
Source: Synthetic (Usually Petroleum-derived, Sometimes Plant-derived)
EWG Rating: 3
Propylparaben
Avoid
A synthetic preservative used to prevent mold and bacteria from growing in personal care products.
Research has shown that propylparaben can act like estrogen, a hormone that helps regulate growth, reproduction, and development. Because of this, it is considered an endocrine disruptor. Animal studies have also linked it to reproductive and developmental concerns. Due to these concerns, its use is restricted in cosmetics in parts of Europe, especially in products intended for young children.
Commonly Found In: Beauty (Lotions, Creams, Shampoo, Conditioner, Makeup)
Pregnancy & Breastfeeding: Because propylparaben can interfere with hormone activity, many experts recommend limiting unnecessary exposure during pregnancy, although human research is still limited.
Source: Synthetic
EWG Rating: 9
Protease
Use In Moderation
Protease is an enzyme that breaks down proteins. It is used in laundry detergents, stain removers, and some cleaning products to help remove protein-based stains like blood, grass, and food.
Protease is generally considered safe when used as intended. However, breathing in enzyme dust or sprays over time can trigger allergies, asthma, or other breathing problems, especially in people who work with these enzymes regularly. It may also cause skin or eye irritation in sensitive individuals.
Commonly Found In: Household (Laundry Detergent, Stain Removers, Dishwashing Detergent, Cleaning Products)
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concerns have been identified from normal household use. The greatest concern is repeated inhalation of enzyme dust or sprays.
Source: Naturally Derived or Synthetic
EWG Rating: 2
Prunus Amygdalus Dulcis (Sweet Almond)
Use in Moderation
A sweet almond-derived ingredient used in beauty and personal care products. The biggest concern is allergy and how the product is used. Almonds can cause allergic reactions in sensitive people, and EWG raises its rating when it is used in sprays or powders that can be breathed in because of respiratory concerns. Topical use in products that aren't inhaled is considered lower concern, so the form of the product matters.
Commonly Found In: Beauty + Personal Care (skincare, haircare, soaps, cleansers, powders, and other almond-containing products)
Pregnancy & Breastfeeding: Generally considered lower concern in topical products that aren't inhaled. Avoid products containing almond ingredients if there is a known almond allergy.
Source: Plant-derived (sweet almond)
EWG Rating: 2–4 depending on usage
PVC (Polyvinyl Chloride)
Avoid
A type of plastic commonly known as vinyl. Many flexible PVC products use phthalates to make the plastic softer. These chemicals can migrate out of the plastic and collect in household dust, and some phthalates are linked to hormone, reproductive, and developmental concerns. PVC can also contain other additives, including heavy metals, depending on how and when it was made. When PVC is burned, it can contribute to the formation of dioxins, highly persistent chemicals linked to cancer, hormone disruption, and reproductive and developmental problems.
Commonly Found In: Household (vinyl flooring, shower curtains, garden hoses, inflatable products, artificial leather & some food packaging); Baby + Kids (some toys & vinyl products); Medical (some tubing, IV bags & other medical devices)
Pregnancy & Breastfeeding: Some phthalates used in flexible PVC have been linked to reproductive and developmental concerns, making exposure especially important during pregnancy and early development
Source: Synthetic (Petroleum-derived Plastic)
EWG Rating: 1-2
Q
Quaternary Ammonium Compounds (Quats)
Avoid
A large group of synthetic ingredients used to disinfect surfaces, soften fabrics, reduce static, and condition hair. Some are also used as preservatives. Certain disinfectant quats have been linked to asthma, skin irritation, and respiratory problems, particularly with repeated exposure to cleaning and disinfecting products. Animal studies on some disinfectant quats have also raised reproductive and developmental concerns. Quats include ingredients such as Benzalkonium Chloride, Cetrimonium Chloride, Cetalkonium Chloride, Behentrimonium Chloride, and DDAC.
Commonly Found In: Household (disinfectant sprays, sanitizing wipes, cleaners & fabric softeners); Beauty + Personal Care (conditioners, hair products & some preservatives)
Pregnancy & Breastfeeding: Animal studies on certain disinfectant quats have raised reproductive and developmental concerns.
Source: Synthetic
EWG Rating: N/A
Quaternium-15
Avoid
A synthetic preservative used to keep bacteria and mold from growing in personal care products.
Quaternium-15 is a formaldehyde-releasing preservative, meaning it slowly releases small amounts of formaldehyde over time to help keep products from spoiling. Formaldehyde is a known human carcinogen and can also trigger skin irritation and allergic reactions, especially in people with sensitive skin. Quaternium-15 is one of the most common preservatives linked to contact allergies, making it an ingredient many people choose to avoid.
Commonly Found In: Beauty & Personal Care (Shampoo, Conditioner, Body Wash, Lotion, Facial Cleanser, Makeup)
Pregnancy & Breastfeeding: Because this ingredient releases formaldehyde, many people choose to limit unnecessary exposure during pregnancy and while breastfeeding.
Source: Synthetic
EWG Rating: 8
R
Red 40 (FD&C Red No. 40)
Avoid
A petroleum-derived synthetic dye used to give foods and other products a red color. Red 40 has been linked to behavioral and attention problems in some children. Research has also raised concerns about DNA damage, inflammation and its potential role in colorectal cancer. Red 40 itself is not currently classified as a carcinogen, but it may contain manufacturing contaminants that can damage DNA, adding to the concern.
Commonly Found In: Food, candy, drinks, supplements, medications, cosmetics & household products
Pregnancy & Breastfeeding: Best to avoid unnecessary exposure to synthetic dyes. There is limited research specifically on Red 40 during pregnancy and breastfeeding.
Source: Synthetic, petroleum-derived
EWG Rating: 3-4
Refined Vegetable / Seed Oils
Use in Moderation
Oils such as soybean, corn, canola, sunflower, safflower and grapeseed oil that are often heavily processed using high heat and other refining steps. Refining can remove some of the naturally occurring antioxidants and nutrients in the oil, and certain oils can break down when exposed to high heat, oxygen or repeated frying. This oxidation can create compounds such as aldehydes that have raised health concerns. Some contaminants can also form during high-temperature oil refining, although the amount varies depending on the oil and how it is processed.
Commonly Found In: Food + Beverage (chips, crackers, fried foods, salad dressings, mayonnaise, sauces, baked goods, granola bars, frozen meals and packaged snacks)
Pregnancy & Breastfeeding: Consider limiting heavily refined and repeatedly heated oils. The main concerns are oxidation products and contaminants that can form during processing and high-heat cooking.
Source: Plant-derived; often refined using multiple processing steps
EWG Rating: N/A
Resorcinol
Avoid
A synthetic ingredient primarily used in permanent hair dyes and some acne treatments. It helps hair color penetrate the hair shaft and can also act as an antiseptic.
Research suggests resorcinol may interfere with normal thyroid hormone production, making it a concern for hormone health. It is also a well-known skin allergen and can cause skin and eye irritation, especially with repeated exposure. Because of these concerns, its use is restricted in cosmetics in several countries.
Commonly Found In: Beauty & Personal Care (Permanent Hair Dye, Hair Bleach, Acne Treatments, Chemical Peels)
Pregnancy & Breastfeeding: Because of its potential effects on thyroid function, many people choose to limit unnecessary exposure during pregnancy and while breastfeeding.
Source: Synthetic
EWG Rating: 9
Retinyl Palmitate (Vitamin A Palmitate)
Avoid (Leave-On Skincare and Excessive Oral Intake)
A form of vitamin A used in fortified foods, supplements, and skincare products. Vitamin A is essential for health, but getting too much vitamin A over time can cause it to build up in the liver, potentially leading to liver damage and other health problems. Research involving more than 22,000 pregnant women also found an increased risk of certain birth defects among those taking high amounts of preformed vitamin A supplements during early pregnancy.
In skincare, studies have found that retinyl palmitate can break down when exposed to UV light and produce reactive molecules that damage cells and DNA in laboratory experiments. A National Toxicology Program study also found that mice treated with retinyl palmitate developed certain skin tumors sooner and more frequently when exposed to simulated sunlight. These findings raise concerns about its use in products exposed to sunlight, although normal topical use has not been shown to cause skin cancer in humans.
Commonly Found In: Food + Beverage (fortified milk, cereals, infant formula, nutrition drinks); Supplements (multivitamins, prenatal vitamins, vitamin A supplements); Beauty + Personal Care (anti-aging creams, moisturizers, eye creams, serums, sunscreens, foundations, lip products)
Pregnancy & Breastfeeding: Excessive intake of preformed vitamin A during pregnancy can cause birth defects. The adult upper limit is 3,000 mcg RAE per day from food and supplements combined. Topical retinoids are generally avoided during pregnancy as a precaution. During breastfeeding, avoid excessive preformed vitamin A intake and discuss topical retinoid use with a healthcare professional.
Source: Preformed vitamin A (retinyl ester)
EWG Rating: 1–9, depending on concentration and product formulation
Rice Bran Oil
Avoid
An oil made from the outer layer of rice grains. It's commonly used in processed foods and for high-heat cooking because of its mild flavor and high smoke point.
Rice naturally absorbs more arsenic from soil and water than many other crops, and because this oil is made from the outer layer of the grain, small amounts can carry over into the finished oil. Rice bran oil is also typically refined using high heat, which can create processing contaminants such as 3-MCPD esters and glycidyl esters. Like many refined seed oils, it is also high in omega-6 fatty acids and is commonly found in ultra-processed foods.
Commonly Found In: Food & Beverage (Cooking Oils, Fried Foods, Snack Foods, Processed Foods)
Pregnancy & Breastfeeding: No specific concerns beyond normal dietary intake.
Source: Plant (Rice Bran)
EWG Rating: 1
Ricinoleth-40
Avoid
An ethoxylated ingredient made from castor oil that helps blend oil and water together in cosmetics and personal care products.
Ricinoleth-40 is made by reacting castor oil with ethylene oxide, a manufacturing process called ethoxylation. This process can leave behind small amounts of contaminants such as 1,4-dioxane and ethylene oxide if they are not properly removed during manufacturing. Although manufacturers can reduce these contaminants through additional purification, they are not required to test for or disclose them on product labels.
Commonly Found In: Beauty & Personal Care (Lotions, Creams, Cleansers, Shampoos, Conditioners, Cosmetics)
Pregnancy & Breastfeeding: Some people choose to limit unnecessary exposure to ethoxylated ingredients during pregnancy and while breastfeeding because of the potential for manufacturing contaminants.
Source: Plant-Derived (Castor Oil) That Has Been Chemically Processed
EWG Rating: 1-2
S
Salicylic Acid (Beta Hydroxy Acid or BHA)
Use in Moderation
An exfoliating ingredient commonly used to treat acne, unclog pores, and remove dead skin cells. Also called beta hydroxy acid or BHA, it can dry or irritate the skin and may increase sensitivity to the sun. Salicylic acid can be absorbed through the skin, with greater exposure possible from higher concentrations, larger areas of skin, and stronger treatments such as chemical peels. Reproductive and developmental effects have been found with higher systemic exposure to salicylates, although this does not mean typical topical skincare use causes these effects.
Commonly Found In: Beauty & Personal Care (Acne Treatments, Facial Cleansers, Toners, Serums, Spot Treatments, Chemical Peels)
Pregnancy & Breastfeeding: Limit higher-strength, leave-on products, large-area use and chemical peels during pregnancy; small amounts of lower-strength topical products result in much lower exposure
Source: Usually Synthetic (Can Also Be Derived from Willow Bark)
EWG Rating: 6
Sodium Benzoate
Use in Moderation
A preservative used to prevent bacteria, yeast, and mold from growing in foods, drinks, and personal care products. When sodium benzoate is combined with vitamin C, small amounts of benzene, a known human carcinogen, can form under certain conditions, with heat and light increasing formation. Studies in children have also found increased hyperactive behavior after consuming mixtures containing sodium benzoate and artificial food dyes, although the studies could not determine which ingredient was responsible.
Commonly Found In: Food & Beverage (Soft Drinks, Fruit Juices, Condiments, Salad Dressings, Packaged Foods), Beauty & Personal Care (Facial Cleansers, Lotions, Shampoo, Cosmetics)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established at typical exposure levels
Source: Synthetic
EWG Rating: 1–2
Sodium Bisulfite
Use in Moderation
A sulfite used as a preservative to prevent foods and products from spoiling or changing color. It can trigger asthma symptoms or allergic-type reactions in people who are sensitive to sulfites, with people who have asthma being particularly susceptible. Inhalation is also a concern when used in sprays or powders.
Commonly Found In: Food & Beverage (Dried Fruit, Wine, Processed Potatoes, Shrimp), Beauty + Personal Care, Pharmaceuticals
Pregnancy & Breastfeeding: No known reproductive or developmental concerns; limit inhalation exposure from sprays or powders
Source: Synthetic
EWG Rating: 5
Sodium Borate (Borax)
Avoid
A naturally occurring mineral used in household cleaners to help remove stains, soften water, and boost cleaning performance. Also called borax or sodium tetraborate, it can irritate the skin, eyes, and lungs, especially when inhaled as a powder. Animal studies have found reproductive and developmental effects with higher exposures, including reduced fetal growth and, at higher amounts, birth defects and pregnancy loss.
Commonly Found In: Household (Laundry Boosters, Powdered Detergents, All-Purpose Cleaners, DIY Cleaning Products)
Pregnancy & Breastfeeding: Limit unnecessary exposure during pregnancy because developmental effects have been found in animal studies, particularly at higher exposures
Source: Naturally Occurring Mineral
EWG Rating: 5
Sodium C14-16 Olefin Sulfonate
Avoid
A strong cleansing ingredient that removes oil, dirt, and product buildup from skin and hair. It creates a rich lather and is often used in products labeled sulfate-free because it is technically a sulfonate, not a sulfate. Although it is not a sulfate, it can still be very stripping. Frequent use may remove too much of the skin’s natural oil, leading to dryness, irritation, and a weakened skin barrier, especially for people with sensitive, eczema-prone, or very dry skin. The manufacturing process can also create impurities called sultones, which have been linked to skin sensitization when they are not properly controlled.
Commonly Found In: Beauty & Personal Care (Shampoo, Body Wash, Facial Cleansers, Bubble Bath)
Pregnancy & Breastfeeding: No specific concerns beyond normal cosmetic use.
Source: Synthetic
EWG Rating: 2
Sodium Carbonate Peroxide
Use in Moderation
A cleaning ingredient that helps lift stains, whiten fabrics, and remove odors by releasing oxygen when mixed with water. It is commonly used in oxygen bleach and powdered laundry products. In its concentrated form, sodium carbonate peroxide can irritate the skin, eyes, and lungs. It is generally considered safe when used as directed, but breathing in the dust or allowing it to sit on the skin may cause irritation.
Commonly Found In: Household (Laundry Detergents, Oxygen Bleach, Stain Removers, Household Cleaning Powders)
Pregnancy & Breastfeeding: Generally considered safe when used as directed. Avoid inhaling dust and prolonged skin contact.
Source: Synthetic
EWG Rating: 2–5 (Higher concern for inhalable products)
Sodium Coco Sulfate
Use in Moderation
A cleansing ingredient made from fatty acids found in coconut oil. It creates a rich lather and helps remove oil, dirt, and buildup from the skin and hair. Although it is naturally derived, Sodium Coco Sulfate is chemically similar to Sodium Lauryl Sulfate (SLS) and can be just as drying for some people. Frequent use may strip away the skin's natural oils, leading to dryness, irritation, and a weakened skin barrier, especially for people with sensitive skin.
Commonly Found In: Beauty & Personal Care (Shampoo, Body Wash, Facial Cleansers, Soap), Household (Laundry Detergents, Household Cleaners)
Pregnancy & Breastfeeding: No specific concerns have been established with normal use.
Source: Naturally Derived (Usually Coconut, Sometimes Palm)
EWG Rating: 1
Sodium Hydroxide
Use in Moderation
A highly alkaline ingredient used to adjust the pH of foods, personal care products, and household cleaners. It also helps turn oils into soap during the soap-making process. In its concentrated form, sodium hydroxide is highly corrosive and can cause severe burns. However, the small amounts used in finished personal care products typically adjust pH or are neutralized during manufacturing. Products containing higher concentrations, such as drain cleaners and oven cleaners, should always be handled with care.
Commonly Found In: Beauty & Personal Care (Soap, Shampoo, Lotion, Hair Color), Household (Drain Cleaners, Oven Cleaners, All-Purpose Cleaners), Food & Beverage (Pretzels, Olives, Cocoa Processing)
Pregnancy & Breastfeeding: No specific concerns have been established when used in finished products as intended.
Source: Synthetic
EWG Rating: 1-4
Sodium Hydroxymethylglycinate
Avoid
A preservative used to prevent the growth of bacteria, yeast, and mold in personal care products.
Sodium Hydroxymethylglycinate is a formaldehyde-releasing preservative, meaning it slowly releases small amounts of formaldehyde over time to keep products from spoiling. Formaldehyde is a known human carcinogen and can also trigger skin irritation and allergic reactions, especially in people with sensitive skin.
Commonly Found In: Beauty & Personal Care (Facial Cleansers, Shampoo, Conditioner, Lotion, Cosmetics)
Pregnancy & Breastfeeding: Because this ingredient releases formaldehyde, limiting unnecessary exposure during pregnancy and while breastfeeding may be prudent.
Source: Synthetic
EWG Rating: 5
Sodium Hypochlorite (Bleach)
Avoid
A chlorine-based chemical used to disinfect, whiten and remove stains. It may also appear on labels as chlorine bleach or hypochlorite. It can irritate the skin, eyes and lungs, and frequent household use has been linked to respiratory symptoms and asthma. Bleach can also react with things like food residue, body oils and soiled laundry to form chlorinated byproducts, including chloroform. Mixing it with acids, such as vinegar, or ammonia can release dangerous gases that can seriously irritate or damage the lungs.
Commonly Found In: Household (Laundry Bleach, Toilet Bowl Cleaners, Mold & Mildew Cleaners, Surface Disinfectants)
Pregnancy & Breastfeeding: Not considered a reproductive toxin, but direct pregnancy research is limited. Avoid breathing bleach fumes and use them with good ventilation
EWG Rating: 3-4
Sodium Laureth Sulfate (SLES)
Avoid
A cleansing ingredient that creates foam and removes oil and dirt from skin and hair. Also called SLES, it is made through a process called ethoxylation, which can leave behind contaminants such as 1,4-dioxane and ethylene oxide if they are not adequately removed during manufacturing. SLES can also irritate the skin, eyes, and respiratory tract, particularly at higher concentrations or with repeated exposure.
Commonly Found In: Beauty & Personal Care (Shampoo, Body Wash, Facial Cleansers, Bubble Bath, Toothpaste), Household (Dish Soap, Laundry Detergent, Household Cleaners)
Pregnancy & Breastfeeding: SLES itself is not known to cause reproductive or developmental harm, but ethoxylation can introduce contaminants including 1,4-dioxane and ethylene oxide, which are carcinogenic concerns. Limiting unnecessary exposure to these potential contaminants may be prudent during pregnancy
Source: Synthetic
EWG Rating: 1-3
Sodium Lauryl Sulfate (SLS)
Use in Moderation
Sodium Lauryl Sulfate is a very effective cleanser, but it can also remove too much of the skin's natural oil. This can leave the skin, scalp, or mouth feeling dry or irritated, especially in people with sensitive skin, eczema, or a weakened skin barrier. Unlike Sodium Laureth Sulfate (SLES), SLS is not made through ethoxylation and is not associated with the same concerns about 1,4-dioxane contamination.
Commonly Found In: Beauty & Personal Care (Shampoo, Body Wash, Facial Cleansers, Toothpaste), Household (Dish Soap, Laundry Detergent, Household Cleaners)
Pregnancy & Breastfeeding: No specific concerns have been established with normal use.
Source: Synthetic or Plant-Derived (Coconut or Palm Oils)
EWG Rating: 1
Sodium Lauryl Sulfoacetate
Use in Moderation
A cleansing and foaming ingredient used in shampoos, body washes, bath products, and other personal care products. Despite the similar name, Sodium Lauryl Sulfoacetate (SLSa) is not the same as Sodium Lauryl Sulfate (SLS). It is generally considered a lower concern overall, but human testing has shown that it can cause skin irritation, even at relatively low concentrations, with the concern becoming more relevant for sensitive or compromised skin and with frequent exposure.
Commonly Found In: Beauty (shampoo, body wash, facial cleansers, bubble bath, bath bombs)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns are established at typical cosmetic exposure. The main concern is irritation, especially if skin is already sensitive
Source: Synthetic
EWG Rating: 1
Sodium Nitrate
Use in Moderation
A preservative most commonly added to cured and processed meats to help prevent bacterial growth, preserve color, and extend shelf life. Sodium nitrate itself has not been shown to be carcinogenic or genotoxic in the available research. The concern is that nitrate can be converted into nitrite in the body, which under certain conditions can then contribute to the formation of N-nitroso compounds, including some carcinogenic nitrosamines. This is most relevant when nitrates are added to processed meats, rather than naturally occurring nitrates found in vegetables, which also contain antioxidants that can help limit nitrosamine formation. Because of this, regularly consuming processed meats with added sodium nitrate is best limited.
Commonly Found In: Food + Beverage (cured meats, bacon, ham, sausage, deli meats); occasionally Beauty (facial creams, moisturizers, serums, and anti-aging products)
Pregnancy & Breastfeeding: No clear reproductive or developmental toxicity has been established for sodium nitrate itself. Limiting processed and cured meats containing added nitrates during pregnancy and breastfeeding is still a reasonable way to reduce unnecessary exposure to nitrate/nitrite additives and potential N-nitroso compound formation
Source: Synthetic when used as a food or product additive; nitrate also occurs naturally in foods and water
EWG Rating: 1
Sodium Nitrite
Avoid
A synthetic preservative most commonly used in processed and cured meats to prevent bacterial growth, preserve color, and extend shelf life. The biggest concern isn't simply Sodium Nitrite on its own, but what it can form under certain conditions. Nitrite can react with proteins and other compounds to create nitrosamines, a group of chemicals that includes known and probable carcinogens. High-heat cooking and processing can increase the formation of some nitrosamines, which is one reason regularly eating processed meats containing added nitrites is best limited. Sodium Nitrite can also show up in some cosmetics and household products, where there are additional restrictions and concerns around concentrated exposure.
Commonly Found In: Food + Beverage (bacon, hot dogs, deli meats, sausage, ham and other cured meats); occasionally Beauty + Household
Pregnancy & Breastfeeding: Limit added nitrites during pregnancy and breastfeeding, particularly from frequently consumed processed and cured meats. This is different from naturally occurring nitrates found in vegetables
Source: Synthetic when used as an additive
EWG Rating: 4
Sodium Percarbonate
Use in Moderation
An oxygen-based bleaching and cleaning ingredient made from sodium carbonate and hydrogen peroxide. Once mixed with water, it releases hydrogen peroxide, which helps lift stains, whiten laundry, and break down grime. Concentrated sodium percarbonate can irritate the skin and can cause serious eye irritation, so powders should be handled carefully. Once diluted and used as directed in household cleaning products, it is a lower-concern option.
Commonly Found In: Household (oxygen bleach, laundry boosters, stain removers, dishwasher detergents, cleaning powders)
Pregnancy & Breastfeeding: No specific reproductive concerns are established for normal household use, but avoid inhaling concentrated powder and protect the skin and eyes when handling it
Source: Synthetic
EWG Rating: N/A
Sodium Phosphate
Use in Moderation
A group of phosphate salts added to processed foods to improve texture, retain moisture, stabilize ingredients, and extend shelf life. Phosphorus is an essential mineral naturally found in many foods, so the concern isn't phosphorus itself. Added phosphates are absorbed more readily than naturally occurring phosphorus in many whole foods, which can make it easier to consume larger amounts when eating a lot of processed foods. Excess phosphorus is especially important for people with impaired kidney function, and consistently high intake may also affect cardiovascular and bone health.
Commonly Found In: Food + Beverage (processed meats, processed cheese, baked goods, packaged foods, fast food, some beverages)
Pregnancy & Breastfeeding: Phosphorus is essential during pregnancy and breastfeeding, but unnecessary phosphate additives from heavily processed foods are best limited rather than intentionally increased
Source: Synthetic/mineral-derived
EWG Rating: 1
Sodium Polyacrylate
Use in Moderation
A synthetic ingredient used to absorb moisture and help thicken products. It is made from acrylic acid, and small amounts of leftover acrylic acid can remain after manufacturing if not properly controlled. The finished ingredient is not expected to easily absorb through the skin and is considered fairly low concern with normal use. It can cause irritation, especially in concentrated or powdered forms, and because it is a synthetic polymer, it does not easily break down in the environment.
Commonly Found In: Beauty (moisturizers, creams, lotions, serums, makeup, hair products); Household + Baby (laundry products, cleaning products, disposable diapers, absorbent pads)
Pregnancy & Breastfeeding: No known reproductive or developmental concerns with normal use. The finished ingredient is not expected to easily absorb through the skin
Source: Synthetic (made from acrylic acid)
EWG Rating: 1-2
Sodium Saccharin
Use in Moderation
An artificial sweetener used to make products taste sweet without adding sugar. In personal care products, it is commonly added to toothpaste and mouthwash to improve the taste. Newer research is looking at how artificial sweeteners like saccharin may affect the gut microbiome and blood sugar response. Sodium Saccharin may disrupt your gut microbiome. Because it provides no nutritional benefit and there are still questions around frequent consumption, this is an ingredient best used in moderation, especially in foods and drinks consumed regularly.
Commonly Found In: Beauty (toothpaste, mouthwash, lip products); Food + Beverage (diet drinks, sugar-free foods, tabletop sweeteners, processed foods)
Pregnancy & Breastfeeding: Saccharin can cross the placenta, and some medical guidance recommends limiting or avoiding it during pregnancy. Exposure from toothpaste or mouthwash that is spit out is much lower than regularly consuming it in foods or drinks
Source: Synthetic
EWG Rating: 1
Sodium Silicate
Use in Moderation
A mineral-based ingredient used to help clean, control pH, prevent corrosion, and bind ingredients together. The biggest concern with Sodium Silicate is irritation. Concentrated forms can irritate the skin, eyes, and respiratory tract, although the risk is much lower when it is diluted in a finished product. This is an ingredient where concentration and how you're exposed to it really matter, so extra care should be taken with concentrated cleaning products and powders.
Commonly Found In: Household (laundry detergent, dishwasher detergent, cleaning powders, degreasers, soaps, surface cleaners)
Pregnancy & Breastfeeding: No clear reproductive or developmental concerns have been established with normal household exposure. Avoid breathing concentrated powders or sprays and limit direct skin contact with concentrated products
Source: Synthetic/mineral-derived
EWG Rating: 2-3
Sodium Triphosphate (Sodium Tripolyphosphate)
Use in Moderation
A phosphate additive used to help foods hold onto moisture and improve their texture. Also called sodium tripolyphosphate or STPP, it is especially common in seafood, where it can make fish or shrimp retain more water and appear firmer or plumper. Added phosphates are absorbed more readily than much of the phosphorus naturally found in food. Regularly consuming large amounts can increase the body's phosphate load, which is particularly concerning for people with impaired kidney function.
Commonly Found In: Food + Beverage (shrimp, scallops, fish fillets, processed seafood, processed meats, some packaged foods)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established at typical food exposure. Limiting heavily processed foods with added phosphates is a reasonable way to reduce unnecessary intake
Source: Synthetic/mineral-derived
EWG Rating: N/A
Sodium Coco-Sulfate
Use in Moderation
A cleansing and foaming surfactant made from fatty acids found in coconut oil. Even though it comes from coconut, it goes through chemical processing to create the finished surfactant and contains a mixture of sulfate detergents. It is sometimes marketed as a gentler alternative to SLS, but it can still strip natural oils from the skin and cause dryness or irritation, especially with frequent use or on sensitive or compromised skin.
Commonly Found In: Beauty (shampoo, body wash, facial cleansers, hand soap, bar soap, toothpaste)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established with normal topical use. The main concern is skin and eye irritation
Source: Plant-derived + chemically processed (commonly coconut-derived)
EWG Rating: 1
Sorbic Acid
Use in Moderation
A preservative used to prevent mold, yeast, and other microbial growth. It can be naturally occurring, but the Sorbic Acid used in commercial products is typically manufactured. It is generally considered of low concern at the small amounts used as a preservative, but it can irritate the skin and has caused contact dermatitis in some people. This makes it more important to watch for if you have sensitive, reactive, or compromised skin.
Commonly Found In: Beauty (moisturizers, creams, lotions, facial serums, cleansers, shampoo, makeup); Food + Beverage (cheese, baked goods, sauces, beverages, packaged foods); Supplements (liquid supplements, gummies, syrups)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established at typical food or cosmetic exposure. The main concern with topical products is irritation or sensitivity
Source: Usually synthetic; can occur naturally
EWG Rating: 2
Sorbitan Sesquioleate
Use in Moderation
An emulsifier that helps oil and water stay mixed together in creams, lotions, makeup, and topical treatments. The main concern is skin sensitivity. Sorbitan Sesquioleate is a known contact allergen and can trigger allergic contact dermatitis in some people, although reactions appear to be relatively uncommon overall. It may be more important to avoid if you have eczema, very sensitive skin, or a known allergy to this ingredient.
Commonly Found In: Beauty (moisturizers, creams, lotions, makeup, sunscreen); topical products (corticosteroid creams, antifungal creams, antibiotic ointments, retinoid treatments)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established with normal topical exposure. The main concern is contact allergy and skin irritation
Source: Synthetic/plant-derived components
EWG Rating: 1
Sorbitol
Use in Moderation
A sugar alcohol used to add sweetness and help products hold onto moisture. Small amounts are generally well tolerated, but Sorbitol is not completely absorbed in the small intestine. Larger amounts can pull water into the intestines and be fermented by gut bacteria, which can lead to gas, bloating, cramping, and diarrhea. This is especially important for people with sensitive digestion or when Sorbitol is regularly consumed in sugar-free foods. There isn't enough evidence to simply say that Sorbitol "disrupts good gut bacteria," so that claim should be removed.
Commonly Found In: Food + Beverage (sugar-free gum, candy, protein bars, diet foods, baked goods); Beauty + Oral Care (toothpaste, mouthwash, skincare)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established at normal intake. Larger amounts can still cause digestive upset
Source: Naturally occurring in some fruits; commercially produced forms are usually manufactured from glucose
EWG Rating: 1
Soy Lecithin
Use in Moderation
An emulsifier made from soy that helps oil and water stay mixed and improves the texture of foods and supplements. Conventional soy lecithin is typically produced during soybean oil processing, which commonly uses hexane as an extraction solvent, although most of the solvent is removed during processing. Conventional soy may also be genetically engineered. Choosing certified organic soy lecithin avoids genetically engineered soy and provides stricter controls on the processing methods used.
Commonly Found In: Food + Beverage (chocolate, protein bars, baked goods, nut butters, packaged foods); Supplements (softgels, powders, protein supplements, vitamins)
Pregnancy & Breastfeeding: No specific pregnancy or breastfeeding concern has been established for soy lecithin at typical food amounts. Those wishing to reduce exposure to processing solvents or GMO crops can choose organic soy lecithin
Source: Soy-derived; highly processed
EWG Rating: N/A
Soy Protein Isolate
Use in Moderation
A highly processed form of soy made by removing much of the soybean's fat and carbohydrates and concentrating the remaining protein. The finished ingredient is usually around 90% protein. The biggest concern isn't that soy protein isolate is inherently toxic, but that it is a highly processed ingredient commonly made from conventional soy. Soy is one of the major genetically engineered crops in the U.S., so choosing organic or Non-GMO Project Verified products can help avoid GMO soy. Whole or less processed protein sources are generally a better everyday choice when available.
Commonly Found In: Food + Beverage (protein powders, protein bars, meal-replacement shakes, meat alternatives, high-protein snacks, processed foods)
Pregnancy & Breastfeeding: Soy foods can be part of a healthy diet during pregnancy and breastfeeding. There is no established reason to avoid Soy Protein Isolate solely because of pregnancy, although choosing less processed or organic sources when possible may be preferred
Source: Soy-derived + highly processed
EWG Rating: N/A
Soybean Oil
Use in Moderation
An oil extracted from soybeans and widely used in packaged foods and restaurant cooking. Conventional soybean oil is commonly made from genetically engineered soy and is typically highly refined, with processing that may include hexane extraction. It is also high in polyunsaturated fats that are more prone to oxidation when repeatedly heated at high temperatures. Choosing organic or expeller-pressed soybean oil can reduce concerns around GMO crops and solvent extraction.
Commonly Found In: Food + Beverage (Salad Dressings, Mayonnaise, Chips, Crackers, Baked Goods, Fried Foods, Sauces, Packaged Foods), Supplements (Softgel Capsules and Oil-Based Supplements)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established for normal dietary intake. Focus on getting dietary fats from a variety of minimally processed sources
Source: Plant-derived (soybeans); commonly refined and solvent-extracted
EWG Rating: N/A
Spearmint Oil (Mentha Spicata)
Use in Moderation
An essential oil distilled from spearmint leaves, used to add mint flavor or scent to products. Even though it is naturally derived, essential oils are highly concentrated. Spearmint Oil can irritate the skin and eyes and may cause an allergic skin reaction in some people, especially when used undiluted or at higher concentrations. Quality and sourcing also matter with essential oils. Independent testing of other popular essential oils has found phthalate contamination, although Spearmint Oil itself was not tested in that investigation. Choosing brands that test their oils for purity and contaminants can help reduce this concern.
Commonly Found In: Beauty + Oral Care (toothpaste, mouthwash, lip products, soaps, lotions, skincare, fragrance products); Food + Beverage (gum, mint-flavored foods and beverages)
Pregnancy & Breastfeeding: There isn't enough research on concentrated Spearmint Oil during pregnancy or breastfeeding to establish its safety. Amounts used as food flavoring are different from concentrated essential-oil exposure, so avoid ingesting concentrated Spearmint Oil during pregnancy or breastfeeding unless advised by a qualified healthcare professional
Source: Natural (distilled from Mentha spicata)
EWG Rating: 2-3
Stearalkonium Bentonite
Use in Moderation
A modified clay ingredient used to thicken products, keep pigments evenly distributed, and improve texture. It is made by treating bentonite clay with a quaternary ammonium compound so the clay works better in oil-based formulas. Concerns include possible skin or eye irritation and the use of a quaternary ammonium compound during manufacturing. However, because the finished ingredient behaves differently from disinfecting quats used in household cleaners, it shouldn't automatically be given the same risk profile.
Commonly Found In: Beauty (foundation, concealer, lipstick, mascara, eyeliner, sunscreen, creams, lotions)
Pregnancy & Breastfeeding: There isn't enough ingredient-specific evidence to identify a reproductive or developmental concern with normal cosmetic exposure. Avoiding products that cause irritation is the more practical concern
Source: Modified mineral clay
EWG Rating: 2-3
Spice Extractive
Use in Moderation
Avoid (Undisclosed Blend)
A concentrated flavoring made by extracting the flavor and aroma compounds from spices. The label “spice extractive” doesn't necessarily tell you which spices were used or how they were extracted. Extraction can involve solvents such as alcohol, acetone, hexane, or other approved solvents, and small amounts of certain solvents are legally allowed to remain in spice extracts. Because the extraction method and potential solvent residues aren't typically disclosed on the ingredient label, there isn't enough information to fully evaluate the ingredient.
Commonly Found In: Food + Beverage (Sausages, Processed Meats, Sauces, Marinades, Soups, Chips, Crackers, Seasoning Blends, Packaged Foods)
Pregnancy & Breastfeeding: No specific reproductive or developmental effects have been established, but choosing clearly identified spices or more transparent flavor ingredients can reduce unnecessary exposure to undisclosed processing solvents
Source: Plant-derived + processed
EWG Rating: N/A
Stearalkonium Chloride
Avoid
A synthetic conditioning ingredient that belongs to a group of chemicals called quaternary ammonium compounds, or quats. It is used to soften hair, reduce static and make products feel smoother. Stearalkonium chloride can irritate the skin and eyes, and EWG flags it for allergy and immune concerns and use restrictions. Research on some other quats has also raised reproductive, endocrine and neurological concerns, although these effects have not been established specifically for stearalkonium chloride.
Commonly Found In: Beauty + Personal Care (Conditioners, Hair Masks, Detanglers, Leave-In Conditioners, Hair Color, Styling Products)
Pregnancy & Breastfeeding: Specific pregnancy safety data is lacking. Because broader research on some quats has raised reproductive concerns, limit unnecessary exposure during pregnancy
Source: Synthetic
EWG Rating: 7
Stearamide MEA
Use in Moderation
A synthetic ingredient used to thicken products, boost foam, and help ingredients stay mixed together. It is made using monoethanolamine (MEA). The main concern is nitrosamine contamination. Under certain formulation conditions, ingredients made with ethanolamines can react with other ingredients to form nitrosamines, some of which are carcinogenic. Proper manufacturing can greatly reduce this concern, but there is no way to tell from an ingredient label how well impurities and nitrosamine formation have been controlled. It can also irritate sensitive skin.
Commonly Found In: Beauty (shampoo, conditioner, body wash, facial cleansers, creams, lotions)
Pregnancy & Breastfeeding: No clear reproductive or developmental concerns have been established from normal cosmetic exposure. Because nitrosamine contamination is the larger concern, limiting unnecessary exposure during pregnancy and breastfeeding is a reasonable precaution
Source: Synthetic (made from stearic acid + MEA)
EWG Rating: 1
Sucralose
Use in Moderation
An artificial sweetener made by chemically changing sugar so it tastes much sweeter without providing the same calories. Human studies have found that regular consumption may alter gut bacteria and affect how the body responds to blood sugar and insulin. How often and how much is consumed matters, especially when sucralose is used regularly across multiple foods, drinks and supplements.
Commonly Found In: Food + Beverage (Diet Drinks, Sugar-Free Foods, Flavored Coffee Products, Protein Bars, Desserts), Supplements (Protein Powders, Electrolyte Powders, Greens Powders, Flavored Supplements), Oral Care (Toothpaste, Mouthwash)
Pregnancy & Breastfeeding: Sucralose can cross the placenta and enter breast milk, so frequent exposure may be worth limiting during pregnancy and breastfeeding
Source: Synthetic
EWG Rating: 1
Sulfites
Use in Moderation
A group of preservatives used to prevent foods from browning, oxidizing or spoiling. Sulfites can cause significant reactions in sensitive individuals, especially those with asthma, including wheezing, difficulty breathing, hives and flushing. They may appear on labels as sulfur dioxide, sodium sulfite, sodium bisulfite, sodium metabisulfite, potassium bisulfite or potassium metabisulfite. In the U.S., foods containing 10 ppm or more of sulfites must disclose them on the label.
Commonly Found In: Food + Beverage (Wine, Dried Fruit, Bottled Lemon and Lime Juice, Some Shrimp, Processed Potatoes, Condiments, Pickled Foods)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established at permitted food levels. Those with asthma or a known sulfite sensitivity should be especially cautious
Source: Naturally occurring or added as preservatives
EWG Rating: N/A
Sulfur Dioxide
Use in Moderation
A preservative and antioxidant that belongs to the sulfite family. It is used to prevent browning, oxidation and microbial growth in foods and drinks. Sulfur dioxide can trigger asthma symptoms and allergy-like reactions in people who are sensitive to sulfites, including wheezing, difficulty breathing, hives and flushing. Breathing sulfur dioxide can also irritate and narrow the airways, with people who have asthma being particularly sensitive.
Commonly Found In: Food + Beverage (Wine, Dried Fruit, Fruit Juices, Processed Potatoes, Preserved Fruits and Vegetables)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established at permitted food levels. Those with asthma or sulfite sensitivity should be especially cautious
Source: Naturally occurring during some fermentation or added as a preservative
EWG Rating: 3
Sunflower Oil
Use in Moderation
An oil made from sunflower seeds that can vary depending on how it is processed and the type of sunflower used. Also called sunflower seed oil or Helianthus annuus seed oil, conventional sunflower oil is often refined and may be extracted using solvents such as hexane, and studies have detected residual hexane in some finished oils. High-temperature refining can also form processing contaminants including 3-MCPD esters and glycidyl esters. Traditional sunflower oil is high in polyunsaturated fats that oxidize more easily with prolonged or repeated high heat, forming breakdown products including certain aldehydes. High-oleic sunflower oil is more resistant to oxidation.
Commonly Found In: Food + Beverage (chips, crackers, salad dressings, mayonnaise, sauces, baked goods, fried foods, packaged snacks); Supplements (softgels and oil-based supplements
Pregnancy & Breastfeeding: Sunflower oil itself has no established reproductive or developmental concern. Choosing less-refined oils and avoiding repeatedly heated or oxidized oils can help reduce exposure to processing and oxidation byproducts
Source: Plant-derived; may be refined, solvent-extracted, or mechanically pressed
EWG Rating: 1
T
T-Butyl Alcohol
Avoid
A synthetic alcohol used as a solvent, fragrance ingredient, and to denature alcohol in personal care products. It can irritate the eyes and respiratory system, especially when inhaled. There are also cancer concerns from animal studies. The EPA currently describes T-Butyl Alcohol as having suggestive evidence of carcinogenic potential, based on tumors seen in laboratory animals. This does not prove that the small amounts used in cosmetics cause cancer, but the combination of inhalation exposure, irritation, and cancer concerns makes this an ingredient worth avoiding when possible.
Commonly Found In: Beauty (perfume, fragrance sprays, hairspray, nail products, aftershave, products containing denatured alcohol)
Pregnancy & Breastfeeding: Avoiding unnecessary inhalation exposure is a reasonable precaution and take into account that there are cancer concerns
Source: Synthetic
EWG Rating: 3
Talc
Avoid
A naturally occurring mineral used to absorb moisture, prevent caking, and give powders and makeup a smoother texture. Talc deposits can occur near asbestos in the earth, which creates a risk of asbestos contamination if the talc is not properly sourced and tested. Asbestos is a known carcinogen and is especially dangerous when inhaled. FDA continues to monitor and test talc-containing cosmetics for asbestos.
There are also concerns beyond asbestos contamination. In its latest evaluation, IARC classified talc itself as probably carcinogenic to humans (Group 2A) after reviewing human, animal, and mechanistic evidence. This makes inhalable powders and repeated exposure particularly important to consider.
Commonly Found In: Beauty (face powder, setting powder, blush, bronzer, eyeshadow, dry shampoo, body powder, baby powder)
Pregnancy & Breastfeeding: Avoiding inhalable talc powders can help reduce unnecessary respiratory exposure. Talc used around the genital area is also best avoided
Source: Natural mineral
EWG Rating: 8
TBHQ (Tert-Butylhydroquinone)
Use in Moderation
A synthetic preservative added to foods to keep oils and fats from going rancid and extend shelf life. Research has raised concerns about how frequent exposure to TBHQ may affect the immune system, including changes in T-cell activity and normal immune signaling. Other laboratory and animal studies have found cellular and DNA-related effects at higher exposures, although these findings do not mean that the amounts allowed in food have been proven to cause cancer in humans. Because the concerns appear to increase with the amount and frequency of exposure, this is an ingredient worth limiting, especially when it is regularly consumed in processed foods.
Commonly Found In: Food + Beverage (packaged snacks, crackers, instant noodles, frozen foods, fried foods, processed oils and other packaged foods containing fats and oils)
Pregnancy & Breastfeeding: Human research during pregnancy and breastfeeding is limited. Reducing frequent exposure can help limit overall intake
Source: Synthetic
EWG Rating: 1-3
TEA-Laureth Sulfate
Avoid
A synthetic cleansing and foaming ingredient used in shampoos, body washes, and other personal care products. Laureth means the ingredient is ethoxylated, a manufacturing process that can create unwanted contaminants such as 1,4-dioxane if they are not properly removed during processing.
There is also an additional concern from the triethanolamine (TEA) portion of the ingredient. CIR specifically states that TEA-Laureth Sulfate should be formulated to avoid irritation, should control free DEA impurities, and should not be used in formulas where N-nitroso compounds can form. Some nitrosamines are carcinogenic. Because this ingredient combines an ethoxylated surfactant with additional impurity and nitrosamine concerns, it falls into Avoid.
Commonly Found In: Beauty (shampoo, body wash, bubble bath, facial cleansers, liquid hand soap)
Pregnancy & Breastfeeding: There isn't clear evidence of reproductive harm from normal cosmetic exposure, but avoiding unnecessary exposure to ethoxylated ingredients and ingredients with potential nitrosamine contamination is a reasonable precaution
Source: Synthetic
EWG Rating: 1-5
Tea Tree Oil (Melaleuca Alternifolia)
Use in Moderation
An essential oil distilled from tea tree leaves and commonly used for its antimicrobial properties. Tea Tree Oil can irritate the skin and cause allergic reactions, especially when it's used undiluted or has been exposed to air and oxidized. There are also questions around possible hormone activity because laboratory studies have found estrogen-like and anti-androgen effects. A small number of cases have also linked products containing Tea Tree Oil with breast development in children, but there isn't enough human evidence to prove that Tea Tree Oil causes hormone disruption.
Commonly Found In: Beauty + Personal Care (acne products, shampoo, scalp treatments, deodorant, soaps, skincare and essential oil blends); Household (some natural cleaners)
Pregnancy & Breastfeeding: Safety information is limited. Avoid ingesting Tea Tree Oil and use properly diluted topical products
Source: Natural essential oil
EWG Rating: 4-6
Tebuconazole
Avoid
A synthetic fungicide used on crops to prevent fungal diseases. Exposure is more likely to come from pesticide residues on treated foods than from seeing Tebuconazole listed as a food ingredient. Toxicology data have raised concerns about reproductive and developmental effects, and EPA has classified Tebuconazole as a possible human carcinogen. PubChem's regulatory hazard information also identifies reproductive toxicity concerns.
Commonly Found In: Food + Beverage exposure may occur through pesticide residues on conventionally treated grains, fruits, vegetables, nuts, and other crops; also used as an agricultural seed treatment
Pregnancy & Breastfeeding: Because developmental and reproductive concerns have been identified in animal toxicology data, reducing unnecessary pesticide exposure during pregnancy and breastfeeding is a reasonable precaution
Source: Synthetic pesticide/fungicide
EWG Rating: N/A
Terpineol
Use in Moderation, Avoid if pregnant
Terpineol refers to a group of four terpene alcohols commonly found in natural essential oils like cardamom, cajuput, and pine oil. While naturally derived and often used for fragrance in personal care and household products, terpineol has been linked to skin irritation, respiratory distress, and potential damage to the lungs, kidneys, heart, and reproductive organs in animal studies.
Commonly Found In: Beauty + Home (Perfumes, soaps, air fresheners, and detergents).
Pregnancy: Best avoided due to limited safety data and potential for endocrine disruption.
Source: Naturally occurring in essential oils but is often synthesized and isolated for commercial use.
EWG Rating: 3-4
Tetrachloroethylene
Avoid
A chemical solvent often used in carpet cleaners and dry cleaning products. Exposure may cause headaches, dizziness, and long-term damage to the liver, kidneys, and immune system. It’s also classified as a possible human carcinogen.
Commonly Found In: Household (Carpet cleaners, drycleaning chemicals, spot cleaners).
Pregnancy: Avoid- may pose risks to fetal development with prolonged exposure.
Source: Synthetic (chlorinated hydrocarbon solvent).
EWG Rating: 10
Tetramethyl Acetyloctahydronaphthalenes
Avoid
A synthetic fragrance compound used to create a musky scent. It’s a known skin and eye irritant and may cause allergic reactions. It’s also classified as an environmental toxin and is restricted in some countries due to concerns over bioaccumulation.
Commonly Found In: Household (air fresheners, scented cleaners, laundry products), Beauty (perfume, shampoo, lotion).
Pregnancy: Avoid — limited safety data and potential for endocrine disruption in humans.
Source: Synthetic
EWG Rating: 3
Tetrahydrolinalool
Use in Moderation
A hydrogenated form of linalool, commonly used as a fragrance ingredient. While it’s naturally derived, it can still cause skin irritation or allergic reactions in sensitive individuals, especially when used in high concentrations or synthetic blends.
Commonly Found In: Beauty + Household (Perfumes, lotions, detergents)
Pregnancy: Caution advised — limited safety data for pregnancy; best used in moderation.
Source: Naturally derived
EWG Rating: 2-3
Tetrasodium EDTA
Avoid
A synthetic ingredient used to bind metals, stabilize formulas, and help preservatives work more effectively. While it has low skin absorption and is considered safe at the amounts typically used in cosmetics, it can irritate the skin and eyes and may increase the penetration of other ingredients in a formula. It is also poorly biodegradable and can persist in waterways, where its ability to bind metals may increase the movement of heavy metals through the environment. Tetrasodium EDTA is also manufactured through chemical processes that can involve formaldehyde and sodium cyanide, although these manufacturing chemicals are not the same as contaminants in the finished ingredient it is something that should be noted.
Commonly Found In: Beauty + Personal Care (shampoo, conditioner, facial cleansers, body wash, lotions, deodorant, liquid soap, baby wipes); Household (laundry products and household cleaners)
Pregnancy & Breastfeeding: Normal topical exposure has not been linked to reproductive or developmental harm. Avoiding it can reduce exposure to an ingredient that may increase penetration of other chemicals in a formula
Source: Synthetic
EWG Rating: 4
Tin Oxide
Use in Moderation
A mineral-based ingredient used to add color, opacity, shimmer, or texture to cosmetics. The safety of Tin Oxide depends partly on the size of the particles and how the product is used. Larger, non-nano Tin Oxide is poorly absorbed through the skin and is considered low risk in typical creams and other non-inhalable cosmetics. The concern increases when Tin Oxide is used in very small nano-sized particles or in loose powders and sprays that can be inhaled. Research on nano Tin Oxide has raised concerns about oxidative stress and cellular damage, while repeated inhalation of Tin Oxide dust is a known occupational lung concern.
Commonly Found In: Beauty (eyeshadow, blush, bronzer, highlighter, face powder, foundation, nail polish, sunscreen and other pigmented or shimmer cosmetics)
Pregnancy & Breastfeeding: Normal skin exposure to non-nano Tin Oxide has not been linked to reproductive or developmental harm. Avoiding loose powders, sprays, and nano forms can help reduce unnecessary inhalation and nanoparticle exposure
Source: Mineral-derived or synthetically manufactured inorganic mineral
EWG Rating: 2-4
Titanium Dioxide
Avoid
A white pigment used to make foods, supplements and coatings look brighter or whiter. The concern is that Titanium Dioxide can contain extremely small particles, including nanoparticles. Research has raised concerns about possible DNA damage from swallowing these particles, and European regulators determined that this risk couldn't be ruled out. Because it doesn't add nutritional value and is mainly used for appearance, it's an unnecessary additive that's easy to avoid.
Commonly Found In: Food + Beverage + Supplements (candy, chewing gum, frosting, baked goods, white coatings, multivitamins, tablets, capsules, gummies and other supplements)
Pregnancy & Breastfeeding: Reproductive or developmental harm from normal exposure hasn't been established, but choosing foods and supplements without Titanium Dioxide can reduce unnecessary oral exposure while questions about DNA damage remain
Source: Mineral-derived and processed
EWG Rating: 1
Titanium Dioxide (CI 77891)
Avoid
A mineral-based ingredient used to whiten and brighten products and commonly used as a pigment in cosmetics. The main concern with Titanium Dioxide is breathing in the particles. Titanium Dioxide has been classified by IARC as possibly carcinogenic to humans based on inhalation evidence, with the concern being greatest for fine airborne particles that can reach the lungs. This makes loose powders, sprays and other products that can easily be inhaled the biggest concern. Titanium Dioxide used in creams and lotions where it isn't airborne does not carry the same inhalation risk.
Commonly Found In: Beauty (loose face powder, setting powder, powdered foundation, blush, eyeshadow, mineral makeup, spray sunscreen and some aerosol products)
Pregnancy & Breastfeeding: Avoid loose powders, sprays and other products where Titanium Dioxide can be inhaled. Creams and lotions containing non-nano Titanium Dioxide are considered lower concern because inhalation isn't expected during normal use
Source: Mineral-derived and processed
EWG Rating: 1
Tocopheryl Acetate
Use in Moderation
A synthetic form of vitamin E used to condition the skin and help keep oils in products from going rancid. It can cause skin irritation or allergic reactions in some people. There are also concerns with how it's made because hydroquinone can be left behind as a contaminant if it isn't properly purified. Hydroquinone can irritate the skin and affect skin pigmentation, and animal studies have raised concerns about cancer. This doesn't mean every product with Tocopheryl Acetate contains hydroquinone, but it makes the quality and manufacturing of the ingredient important.
Commonly Found In: Beauty + Personal Care (moisturizers, serums, sunscreen, lip products, makeup, body lotion, baby lotion, shampoo and conditioner)
Pregnancy & Breastfeeding: Normal topical use hasn't been linked to reproductive or developmental harm. Choosing products that are well-sourced and tested for contaminants can help reduce unnecessary exposure
Source: Synthetic vitamin E derivative
EWG Rating: 2-3
Tocopherol (Vitamin E)
Use in Moderation
A form of vitamin E commonly used as a natural preservative and antioxidant to help keep oils from going rancid. Tocopherol itself isn't considered toxic, but where it comes from and how it's processed can matter. It's often made from refined vegetable oils, especially soybean oil, and can also come from corn, sunflower, or canola oil. Some processing methods may use solvents like hexane, and EWG also flags hydroquinone as a possible contaminant. Hydroquinone can irritate the skin and affect skin pigmentation, and animal studies have raised concerns about cancer. This doesn't mean all Tocopherol contains these contaminants, but it makes sourcing and purification important. When possible, look for non-GMO Tocopherol from a known plant source, especially when it's derived from soy or corn.
Commonly Found In: Food + Beverage + Supplements (packaged foods, oils, protein bars, multivitamins, vitamin E supplements and antioxidant formulas)
Pregnancy & Breastfeeding: Vitamin E is an essential nutrient and normal amounts from food aren't a concern. Choosing Tocopherol from a known, non-GMO source can help provide more transparency around how the ingredient was sourced
Source: Natural or synthetic; natural Tocopherol is commonly derived from soybean, sunflower, corn, canola or other vegetable oils
EWG Rating: 1-2
Transglutaminase
Use in Moderation
An enzyme sometimes called “meat glue” because it helps pieces of protein stick together and improves the texture of processed foods. The form used in food is commonly made through microbial fermentation. Research has raised concerns that microbial Transglutaminase may interact with gluten and the gut lining in ways that could be important for people with celiac disease. This hasn't been proven to cause disease in humans, but enough emerging research makes it worth limiting.
Commonly Found In: Food + Beverage (formed or restructured meats, processed meats, imitation crab, some seafood, baked goods and other processed foods)
Pregnancy & Breastfeeding: No specific reproductive or developmental concerns have been established
Source: Enzyme, commonly made through microbial fermentation
EWG Rating: N/A
Triclosan
Avoid
A synthetic antimicrobial ingredient used to kill or reduce bacteria. Research has raised concerns about hormone disruption, antibiotic resistance, and environmental toxicity. The FDA no longer allows Triclosan in consumer antibacterial hand soaps and body washes because manufacturers didn't provide enough evidence to show that long-term daily use was safe or worked better than regular soap and water. It can also persist in the environment and has been found in people and waterways.
Commonly Found In: Household + Personal Care (some specialty antimicrobial products and older formulations of antibacterial soaps, body washes and personal care products)
Pregnancy & Breastfeeding: Best avoided when possible because of concerns around hormone activity and unnecessary long-term exposure
Source: Synthetic antimicrobial
EWG Rating: 7
Trideceth-9
Avoid
A synthetic ingredient used to help ingredients mix together and improve the texture of products. It's ethoxylated, meaning ethylene oxide is used during manufacturing. This process can leave behind ethylene oxide and 1,4-dioxane if the ingredient isn't properly purified. Ethylene oxide is a known human carcinogen, and 1,4-dioxane is also linked to cancer concerns. Because these are contaminants rather than ingredients intentionally added to the product, they won't appear on the ingredient label.
Commonly Found In: Beauty + Personal Care (cleansers, shampoo, conditioner, hair products, lotions and creams); Household (some cleaning products)
Pregnancy & Breastfeeding: Avoiding ethoxylated ingredients can help reduce unnecessary exposure to potentially carcinogenic manufacturing contaminants
Source: Synthetic + ethoxylated
EWG Rating: 1-2
Triethanolamine (TEA)
Avoid
A synthetic ingredient used to adjust pH and help oil- and water-based ingredients mix together. Also called TEA or trolamine, the biggest concern is that Triethanolamine can react with certain ingredients to form N-nitrosodiethanolamine (NDELA), a carcinogenic nitrosamine that has been detected in TEA-containing cosmetic products. Modern cosmetic regulations restrict the combinations that can promote nitrosamine formation and limit how much can remain in finished products, but contamination can still occur. TEA can also irritate the skin and eyes, especially at higher amounts.
Commonly Found In: Beauty + Personal Care (Facial Cleansers, Moisturizers, Lotions, Shampoo, Conditioner, Shaving Products, Makeup, Sunscreen)
Pregnancy & Breastfeeding: Triethanolamine itself has not been shown to cause reproductive or developmental harm at typical cosmetic exposure, but limiting exposure can reduce the potential for exposure to nitrosamine contaminants
Source: Synthetic
EWG Rating: N/A
Trifluoroacetyl Tripeptide-2
Avoid
A synthetic peptide used in anti-aging skincare to help improve the look of firmness and elasticity. It contains a highly fluorinated CF₃ group and is considered a PFAS. Research shows that Trifluoroacetyl Tripeptide-2 can pass through the skin, making it another potential source of PFAS exposure. Certain well-studied PFAS can remain in the body for years, and exposure has been linked to concerns with the immune system, liver, cholesterol, pregnancy and development, and certain cancers. While these health effects have not been proven for Trifluoroacetyl Tripeptide-2 specifically, avoiding intentionally added PFAS in skincare can help reduce overall exposure.
Commonly Found In: Beauty (anti-aging serums, firming creams, eye creams, moisturizers, neck creams and other anti-aging treatments)
Pregnancy & Breastfeeding: PFAS can cross the placenta and have been found in breast milk and fetal tissues. Because Trifluoroacetyl Tripeptide-2 is a PFAS that can also pass through the skin, it's an unnecessary source of PFAS exposure that's best avoided during pregnancy and breastfeeding.
Source: Synthetic fluorinated peptide (PFAS)
EWG Rating: 10
U
Undecyl Alcohol
Use in Moderation
A fatty alcohol used to soften the skin and add fragrance to personal care products. Unlike drying alcohols like ethanol, fatty alcohols are generally more moisturizing. Undecyl alcohol can irritate the skin and eyes and may cause skin sensitization in some people.
Commonly Found In: Beauty + Personal Care (fragrance, skincare, lotions, creams & some hair products)
Pregnancy & Breastfeeding: Research during pregnancy and breastfeeding is limited.
Source: Plant-derived or synthetic
EWG Rating: 1
Undecylenic Acid
Use In Moderation
A fatty acid usually derived from castor oil and used for its antifungal properties. It can irritate the skin and has caused allergic contact dermatitis in some people, especially with repeated or higher-concentration exposure.
Commonly Found In: Beauty + Personal Care (antifungal creams, nail treatments, foot products, skincare & some personal care products)
Pregnancy & Breastfeeding: Research during pregnancy and breastfeeding is limited.
Source: Plant-derived (usually castor oil)
EWG Rating: 1-2
V
Vegetable Emulsifying Wax
Avoid (Undisclosed Blend)
A blend used to help oil and water mix together and keep creams and lotions from separating. “Vegetable emulsifying wax” doesn't tell you exactly what's in the blend. Some versions contain ethoxylated ingredients like Polysorbate 60, PEGs, or Steareth ingredients, which can contain 1,4-dioxane and ethylene oxide if they aren't properly purified. Both are linked to cancer. The actual ingredients can vary depending on the manufacturer.
Commonly Found In: Beauty + Personal Care (lotions, creams, moisturizers, conditioners & body products)
Pregnancy & Breastfeeding: Depends on the ingredients used in the blend.
Source: Varies (often plant-derived ingredients combined with synthetically processed emulsifiers)
EWG Rating: N/A
Vegetable Oil
Avoid
A broad term that can refer to oils like soybean, canola, corn, sunflower, cottonseed, or a blend of different oils. Many vegetable oils are highly refined using high heat, which can create 3-MCPD esters and glycidyl esters. Glycidyl esters can release glycidol, which can damage DNA and cause cancer, while 3-MCPD has caused kidney and reproductive effects in animal studies. Oils higher in polyunsaturated fats are also more prone to oxidation, especially when exposed to high heat or repeatedly used for frying, which can create potentially harmful oxidation products.
Commonly Found In: Food + Beverage (fried foods, chips, crackers, baked goods, salad dressings, sauces, mayonnaise, frozen foods & other processed foods)
Pregnancy & Breastfeeding: Concerns depend on the type of oil, how it was processed, and how it is used.
Source: Plant-derived (often highly refined)
EWG Rating: 1
Viscose
Use In Moderation
A semi-synthetic fiber made by chemically processing plant cellulose, usually wood pulp, and turning it back into textile fibers. Conventional viscose manufacturing uses carbon disulfide, a chemical linked to neurological, reproductive, hormonal, and cardiovascular effects in workers exposed during manufacturing. The process can also release hazardous pollutants when emissions and wastewater aren't properly controlled. These concerns are mainly tied to how viscose is manufactured rather than wearing the finished fabric.
Commonly Found In: Clothing + Textiles (clothing, underwear, pajamas, bedding, towels & upholstery)
Pregnancy & Breastfeeding: No specific concern has been established from wearing finished viscose fabric.
Source: Plant-derived cellulose that is chemically processed
EWG Rating: N/A
Viscose from Bamboo
Use In Moderation
A semi-synthetic fiber made by chemically breaking down bamboo and turning the cellulose back into textile fibers. Despite often being marketed simply as “bamboo,” the finished fabric is actually viscose or rayon made from bamboo rather than natural bamboo fiber. Conventional viscose manufacturing uses carbon disulfide, a chemical linked to neurological, reproductive, hormonal, and cardiovascular effects in workers exposed during manufacturing. The process can also release hazardous pollutants. These concerns are mainly tied to how the fabric is manufactured rather than wearing the finished material.
Commonly Found In: Clothing + Textiles (underwear, pajamas, leggings, shirts, socks, bedding, towels & baby clothing)
Pregnancy & Breastfeeding: No specific concern has been established from wearing finished bamboo viscose.
Source: Bamboo-derived cellulose that is chemically processed
EWG Rating: N/A
Vital Wheat Gluten
Use In Moderation
A concentrated wheat protein made by washing most of the starch out of wheat flour, leaving behind the gluten. It is used to improve the stretch, structure, and chewiness of foods and is the main ingredient in seitan. Because it is a concentrated source of gluten, it must be avoided by people with celiac disease and can also cause reactions in people with wheat allergy or certain wheat or gluten sensitivities.
Commonly Found In: Food + Beverage (seitan, meat alternatives, breads, baked goods, pizza dough & other high-protein foods)
Pregnancy & Breastfeeding: No specific concerns for people who tolerate wheat and gluten.
Source: Wheat-derived
EWG Rating: N/A
Vitamin A Palmitate (Retinyl Palmitate)
Use In Moderation
A form of preformed vitamin A commonly added to fortified foods and supplements. Vitamin A is an essential nutrient, but preformed vitamin A is stored in the body and too much over time can build up and cause toxicity, including liver damage. Excessive intake during pregnancy can also cause birth defects. Total intake matters because preformed vitamin A can come from multiple fortified foods and supplements.
Commonly Found In: Food + Beverage (fortified milk, dairy alternatives, cereals & other fortified foods); Supplements (multivitamins, prenatal vitamins & vitamin A supplements)
Pregnancy & Breastfeeding: Excess preformed vitamin A during pregnancy can cause birth defects. Total intake from food and supplements is especially important.
Source: Synthetic or naturally derived preformed vitamin A
EWG Rating: N/A
VOCs (Volatile Organic Compounds)
Avoid
A broad group of chemicals that easily evaporate into the air and can be released from household products and materials. Health effects depend on the specific VOC and how much you're exposed to. Some can irritate the eyes and respiratory system or affect the nervous system, liver, and kidneys, while certain VOCs are linked to cancer. VOC levels can also build up indoors, especially when products are used without good ventilation. A “low VOC” or “no VOC” label doesn't necessarily mean a product is free from volatile chemicals with health concerns.
Commonly Found In: Household (cleaners, disinfectants, paints, solvents, air fresheners, fragrances, adhesives, furniture & building materials)
Pregnancy & Breastfeeding: Depends on the specific VOC and level of exposure.
Source: Varies
EWG Rating: N/A
W
X
Xylitol
Use In Moderation
A sugar alcohol used as a lower-calorie sweetener in foods and oral care products. Larger amounts can cause digestive issues like bloating, gas, cramping, and diarrhea, with tolerance varying from person to person. Xylitol is also highly toxic to dogs and can cause severe low blood sugar, seizures, liver failure, and even death if ingested.
Commonly Found In: Food + Beverage (sugar-free gum, candy, baked goods, desserts & some nut butters); Oral Care (toothpaste, mouthwash & mints); Supplements & Medications
Pregnancy & Breastfeeding: No specific concerns have been identified from normal human use.
Source: Naturally occurring sugar alcohol; commercial xylitol is typically produced from plant-derived materials
EWG Rating: 1
Y
Z
Zeolite
Use In Moderation
A group of naturally occurring porous minerals that can bind certain substances. Clinoptilolite is one type commonly sold in supplements. Quality and purity can vary, and testing of commercial zeolite supplements has found heavy metals and products that didn't contain the type of zeolite claimed on the label. Look for third-party, batch-specific testing that confirms clinoptilolite identity and gives actual results for lead, arsenic, cadmium, and mercury. Because zeolite can bind substances in the digestive tract, it may also affect the absorption of medications or nutrients taken at the same time.
Commonly Found In: Supplements (zeolite powders, capsules & “detox” products); Food + Beverage (certain zeolite-type compounds may be used as anti-caking agents)
Pregnancy & Breastfeeding: Human safety research during pregnancy and breastfeeding is limited.
Source: Naturally occurring mineral
EWG Rating: 1
Zinc Pyrithione (Pyrithione Zinc)
Avoid
An ingredient used to help control dandruff by slowing the growth of yeast on the scalp. While it can be effective, research has raised concerns about its potential effects on reproduction and development. Because of these concerns, the “European Union banned zinc pyrithione in cosmetic products in 2022 after experts could not establish a safe level for cosmetic use. It may also cause skin irritation or allergic reactions in some people.”
Commonly Found In: Beauty & Personal Care (Dandruff Shampoos, Scalp Treatments, Some Soaps)
Pregnancy & Breastfeeding: Because studies have raised concerns about reproductive and developmental effects, limiting unnecessary exposure may be especially important during pregnancy and breastfeeding.
Source: Synthetic
EWG Rating: 6
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