Preservatives may be used in cosmetics to prevent the growth of harmful bacteria and mold. Parabens and formaldehyde-releasing preservatives are commonly used preservatives in cosmetic and personal care products.

FOUND IN: Fragrance, lipstick, shampoos, conditioners, lotions, moisturizer, facial and shower cleansers, nail polish, nail glue, hair gel, hair- smoothing products, baby shampoo, body wash/soap, color cosmetics and anti-aging products.

WHAT TO LOOK FOR ON THE LABEL: Formaldehyde, DMDM hydantoin, quaternium-15, imidazolidinyl urea, diazolidinyl urea, polyoxymethylene urea, sodium hydroxymethylglycinate, 2-bromo-2-nitropropane-1,3-diol (bromopol) and glyoxal. Ethylparaben, MORE...

butylparaben, methylparaben, propylparaben, isobutylparaben, isopropylparaben, other ingredients ending in –paraben. Benzylate, benzoic acid, and benzyl ester. Methylisothiazolinone (MIT): 2-methyl-4-isothiazoline-3-one, Neolone 950 preservative, MI, OriStar MIT and Microcare MT. Methylchloroisothiazolinone (CMIT): 5-Chloro-2-methyl-4-isothiazolin-3-one and MCI. Phenoxyethanol, 2-Phenoxyethanol, Euxyl K® 400 (mixture of Phenoxyethanol and 1,2-dibromo-2,4-dicyanobutane), PhE. Triclosan (TSC) and triclocarban (TCC). Also, check for benzyl alcohol, benzalkonium chloride, citric acid, dehydroacetic acid, essential oils, grapefruit seed extract, lactic acid, levulinic acid, potassium sorbate, sodium dehydroacetate, sodium metabisulfite, sodium salicylate, sorbic acid, vitamin E, zinc pyrithione.

WHAT ARE PRESERVATIVES & WHERE ARE THEY FOUND? Preservatives may be used in cosmetics to prevent the growth of harmful bacteria and mold. Parabens and formaldehyde-releasing preservatives are commonly used preservatives in cosmetic and personal care products. MORE...

Parabens are not water-soluble and can penetrate the skin. As a result, repeated application of a product or multiple products containing parabens could mean almost continuous exposure.[1] Parabens have been found in nearly all urine samples from U.S. adults regardless of ethnic, socioeconomic or geographic backgrounds.[2]

Formaldehyde-releasing preservatives slowly release formaldehyde which kills bacteria in water-based products. A study determined that longer storage time and higher temperature increase the amount of formaldehyde released from formaldehyde-releasing preservatives and could ultimately lead to more severe health concerns.[3]

Other preservatives are emerging as replacements.

In our 2016 report focusing on kids’ makeup products we found at least one paraben, an endocrine disrupting compound, in 34% of products just from reading the labels. Two or three parabens were found in 3% of the products. We also found formaldehyde-releasing preservatives in 3% of the products from label reading.[4]

A recent biomonitoring study conducted at UC Berkeley found a big drop in the chemical body burdens of a dozen California teens who switched up their beauty regime. The girls saw reductions of 25 to 40 percent in 4 endocrine disrupting chemicals – phthalates, parabens, ticlosan, oxybenzone – after only 3 days of switching from products that contained these harmful chemicals to products that did not.[5] This study demonstrates that if you take toxic chemicals out of cosmetics you can take them out of people in just a few days.

HEALTH CONCERNS: Cancer, endocrine disruption, developmental toxicity, reproductive toxicity, irritation, and many other health concerns. MORE...

Parabens: Studies demonstrate that at sufficient concentrations, parabens can increase cell proliferation in human breast cancer MCF-7 cells, which are often used as a sensitive measure of estrogenic activity.[6] Parabens are potential endocrine disruptors due to their ability to mimic estrogen.[7] In cell studies, parabens have been found to weakly bind to estrogen receptors.[8]

Propyl paraben is also a reproductive toxin as it affects the male reproduction system and reduces sperm production and testosterone levels.[9],[10],[11]

Butyl paraben, specifically, appears to disrupt the male reproductive system and affect reproductive organs.[12],[13]

Methyl paraben and other parabens in personal care products can lead to UV-induced damage of skin cells and disruption of cell proliferation (cell growth rate).[14],[15] Of the parabens, methyl paraben is generally of lower concern, because it is less estrogenic.

Ethyl paraben is listed as a potential endocrine disruptor by the TEDX Endocrine Disruption Exchange.[16],[17]

Isobutylparaben exposure in rats has demonstrated increased uterus weight and uterine sensitivity to estrogen in the offspring.[18]

Formaldehyde: Formaldehyde is classified as a known human carcinogen by the National Toxicology Program[19] and the International Agency for Research on Cancer.[20]

Formaldehyde-releasing preservatives: These preservatives release small amounts of formaldehyde over time.

DMDM hydantoin is a formaldehyde-releasing preservative (FRP) used to prevent microbes from growing in water-based products. It can be found in many personal care products.[21]

Diazolydinal urea releases the most formaldehyde of any formaldehyde-releasing preservative.[22]

Imidiazoldinal urea is one of the most common antimicrobial agents used in personal care products and is often combined with parabens.[23]

Quaternium-15 is the most sensitizing of these FRPs and is found in blush, mascara, lotion, and shampoo.[24] A study revealed that about 22.3% of consumers are allergic to quaternium-15.[25]

Bronopol (2-Bromo-2-Nitropropane) is a formaldehyde-releasing preservative. It is listed as a potential endocrine disruptor.[26] It is also very toxic to aquatic life and can cause skin irritation and respiratory irritation.[27],[28]

Isothiazolinones: Studies show that isothiazolinones have caused allergic cosmetic dermatitis[29] in many European countries.[30] [link to isothiazolinone entry]

Methylisothiazolinone (MIT) is one of the most predominant contact allergens found in cosmetic products.[31] MIT has also been linked to organ system toxicity[32] and neurotoxicity.[33]

Methylchloroisothiazolinones (CMIT/MCI) in a clinical study, researchers found that dermal irritation most commonly occurs in products with CMIT and MIT/CMIT mixtures, but is not as common in products with only MIT.[34],[35]

The following preservatives are increasingly used in personal care products. Few studies examine the health effects of these compounds at the levels used in personal care products.

Benzyl benzoate: One study found that benzyl benzoate demonstrated estrogenic responses in a human breast cancer cell line in culture, which indicates the ability of a substance to mimic estrogen.[36] Benzyl Benzoate is a skin and eye irritant and may severely irritate, burn and sting the genitalia and scalp.[37]

Benzyl Alcohol: is used as preservative, solvent and local anesthetic, reported to cause contact urticaria, also known as hives or a skin rash with red, raised, itchy bumps, in some occupational settings.[38] It can be a skin irritant and inhalation of high concentrations may cause central nervous system effects and may cause skin sensitization in repeated or prolonged exposure.[39]

Benzalkonium Chloride: Benzalkonium chloride is linked to occupational asthma.[40] Short-term exposure is corrosive to the eyes, the skin, and the respiratory tract.[41]

Citric Acid: Short-term exposure to citric acid is irritating to the eyes, and skin and the respiratory tract. Long-term (often occupational) exposure may cause erosion of the teeth.[42] It has caused cough in acute inhalation studies of guinea pigs,[43] ataxia, and respiratory depression in mice.[44]

Dehydroacetic Acid: Dehydroacetic acid can lead to seizures in monkeys[45] and severe hemorrhage in multiple organs in rats.[46]

Essential Oils: Essential oils may contain naturally occurring constituents, ingredients such as pulegone or methyleugenol that may be carcinogenic and alter endocrine functioning.[47],[48],[49]

Methyleugenol (eugenyl methyl ether) can affect multiple endocrine systems[50] and is listed as a possible human carcinogen by the NTP,[51] IARC[52] and on The California Proposition 65.[53]

Grapefruit Seed Extract (GSE): Grapeseed extract is a low concern on its own, but may also be an ineffective preservative. It has been found that sometimes GSE is preserved with other preservatives,[54] which lead to both its efficacy and health concerns: benzethonium chloride,[55],[56],[57] methylparaben (see parabens) and triclosan (see below).

Lactic Acid: Lactic acid irritates the skin and the respiratory tract, and is corrosive to the eyes and to the digestive tract when swallowed.[58],[59]

Levulinic Acid: Is known to be a moderate skin and eye irritant and is harmful when ingested.[60]

Phenoxyethanol: Skin exposure to phenoxyethanol has been linked to allergic reactions ranging from eczema and hives[61] to anaphylaxis.[62] Acute nervous system effects have been seen in infants who have had oral exposure to phenoxyethanol.[63] [link to phenoxyethanol entry]

Potassium Sorbate: Potassium sorbate may lead to eye irritation[64] and contact dermatitis.[65]

Sodium Dehydroacetate (DHA-S): DHA-S lead to hemorrhage in multiple organs and prolongation of blood coagulation factors in a study of rats.[66]

Sodium Metabisulfite (SMB): Studies have found that inhaled SMB causes may exacerbate asthma symptoms.[67] SMB has also been found to cause dermatitis[68] in occupational settings.[69]

Sorbic acid: Sorbic acid has been associated with skin irritation, contact urticaria, also known as hives or a skin rash with red, raised, itchy bumps, as well as redness of the skin (erythema), abnormal accumulation of fluid (edema), and inflammation of the skin.[70]

Triclocarban: Triclocarban is a potential endocrine disruptor.[71] Studies have found that exposure to triclocarban in personal care products may amplify the effects of endogenous hormones and enhance testosterone.[72] It is also a skin, eye, and respiratory tract irritant.[73]

Triclosan (TSC): There is evidence that triclosan is an endocrine disruptor[74],[75] and impacts thyroid function.[76],[77] A number of studies indicate that triclosan promotes bacteria that are resistant to both antibiotic medications and antibacterial products.[78],[79] Evidence also shows triclosan bioaccumulates and can harm the environment.[80],[81]

Vitamin E (tocopherol): One or more animal studies show tumor formation at high doses.[82],[83] Dietary supplementation with vitamin E has been shown to significantly increase the risk of prostate cancer among healthy men.[84]

Zinc Pyrithione (Zpt): Studies have found that Zpt induced significant developmental malformations on fish larvae.[85]

Other preservatives: Several other preservatives may be used in personal care products, despite a lack of data on their health effects: anisic acid, salicylic acid, chlorphenism, stearalkonium chloride, sodium salicylate (aspirin), chlorhexidine digluconate, polyaminopropyl biguanide, and neem oil.

VULNERABLE POPULATIONS: Pregnant women, infants/young children, and hair/nail salon workers.

REGULATIONS: Formaldehyde is banned from use in cosmetics and toiletries in Japan and Sweden;[86] in the EU, restricted in personal care products, and labeling is required in products that do contain these chemicals;[87] concentration restrictions in Canada.[88] Some forms of parabens are banned in Denmark (propyl and butyl paraben, their isoforms and salts) in cosmetic products for children up to years.[89] The FDA doesn’t have special rules that apply only to preservatives in cosmetics.[90]

European Regulation The EU regulates what and how much of various preservatives are allowed in cosmetics. It is one of the most comprehensive regulatory cosmetic/personal care guidelines, setting the standard for many regulatory agencies around the world. Included on the list are preservatives such as: triclosan, triclocarban, phenoxyethanol, benzyl benzoate, methylisothiazolinone, zinc pyrithione, benzalkonium chloride, benzyl alcohol, and some essential oils.

HOW TO AVOID: Read labels, and avoid products with most parabens and all formaldehyde-releasing preservatives. If you are sensitive to other ingredients (e.g., allergens like methyisothiazolinone), avoid those ingredients as well.

References

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