Formaldehyde is a carcinogenic impurity released by a number of cosmetic preservatives, including diazolidinyl urea, imidazolidinyl urea, DMDM hydantoin, quaternium-15, 2-bromo-2-nitropropane-1,3-diol, and sodium hydroxylmethylglycinate. According to reviews by the industry-funded Cosmetic Ingredient Review panel, these cosmetic ingredients can release formaldehyde at levels as high as one-tenth that of the original ingredient (CIR 2006). Successful treatment of formaldehyde-triggered contact allergic dermatitis through substitution of body care products free of these preservatives (Flyvholm 1992) is implicit confirmation of the presence of low levels of formaldehyde in these products.<br /><br />The International Agency for Research on Carcinogens (IARC) has classified formaldehyde as 'carcinogenic to humans,' and the U.S. National Toxicology Program has classified it as 'reasonably anticipated to be a human carcinogen,' based on emerging evidence in humans and robust evidence in animals (IARC 2004; NTP 2005). Occupational exposures to formaldehyde gas are linked to nasal and nasopharyngeal cancers (IARC 2004; NTP 2005). Animal studies confirm this link, and also suggest an association between formaldehyde in drinking water and stomach and gastrointestinal cancer and leukemia (NTP 2005). <br /><br />Despite the considerable health concerns associated with this carcinogen, until recently formaldehyde itself was a common ingredient of nail polish. Consumer pressure has now forced many major cosmetics manufacturers to voluntarily remove this ingredient from their nail products. European health protections now limit the concentration of formaldehyde in cosmetics to 0.2%, and require that body care products containing formaldehyde or formaldehyde-releasing ingredients be labeled with the warning 'contains formaldehyde' if the concentration of formaldehyde in the product exceeds 0.05% (SCCPNP 2002). <br /><br />Even the industry-funded Cosmetic Ingredient Review panel recommends that cosmetic products not contain more than 0.2% formaldehyde, and does not consider formaldehyde to be safe in aerosol products (CIR 2006). However, as it stands in the U.S. there are no restrictions on the levels of formaldehyde allowed in any body care products, no requirement to test products made with formaldehyde-releasing preservatives for levels of formaldehyde, and certainly no obligation to inform consumers that the products they use each day are likely to contain a cancer-causing chemical that does not appear on the list of ingredients.<br /><br /> References<br /><br />CIR (Cosmetics Ingredient Review). 2006. 2006 CIR Compendium, containing abstracts, discussions, and conclusions of CIR cosmetic ingredient safety assessments. Washington DC.<br /><br />Flyvholm MA, Menné T. 1992. Allergic contact dermatitis from formaldehyde. A case study focussing on sources of formaldehyde exposure. Contact Dermatitis. 1992 Jul;27(1):27-36.<br /><br />IARC (International Agency for Research on Carcinogens). 2004. Formaldehyde. IARC monographs on the evaluation of carcinogenic risks to humans / World Health Organization, International Agency for Research on Cancer 88.<br /><br />NTP (National Toxicology Program). 2005. National Toxicology Panel 11th Report on Carcinogens: Formaldehyde (Gas). Available: http://ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s089form.pdf [Accessed August 14, 2008].<br /><br />SCCPNP (Scientific Committee on Cosmetic Products and Non-food Products). 2002. Opinion concerning a clarification on the formaldehyde and para-formaldehyde entry in Directive 76/768/EEC on cosmetic products. Opinion: European Comission.