Sunday, May 25, 2008

Are you wearing formaldehyde? Part 2: Preservatives in Cosmetics

In order for cosmetic formulations to be safe and stable (assured "shelf life"), preservatives need to be added. Preservatives act as antimicrobials as these prohibit or retard the growth of microbes. Preservatives can also function as antioxidants as it protects formulations against damage and degradation caused by exposure to oxygen. Antioxidants prevents browning or black spots from forming. However, preservatives are in the science community's watchlist for containing or having the tendency to release formaldehyde.

A couple of weeks ago, I introduced formaldehyde as a chemical currently considered a probable human carcinogen (Class 3) by the World Heath Organization's International Agency for Research on Cancer (IARC) but, classified as a carcinogen by California Proposition 65. According to the California Proposition, formaldehyde starts to become a health risk at 40 micrograms/day of release. When available in low doses as a preservative for fabrics, leather and food; it can cause irritation of the eyes, skin and throat.

Formaldehyde mixes easily with water but not with oil nor grease. It is commonly used as a preservative in aqueous cosmetic formulations such as shampoos, conditioners, shower gels, liquid handwash and bubble bath. Like certain fragrances, it can irritate sensitive skin. It can destroy the skin's natural protective oils, causing dryness, flaking, cracking and dermatitis (skin rash). Furthermore, persons who are dermally sensitive to formaldehyde can have allergic reactions such redness, itching, hives or blisters. It is therefore one of the chemicals used in an allergy patch test.

Formaldehyde has been banned in Europe and Japan. The European Union's EU Cosmetic Directive (76/768/EC) currently restricts the presence of formaldehyde in aerosol sprays. Oral hygiene products such as mouthwashes must not contain 0.1% of formaldehyde while externally applied cosmetics and toiletries must not contain more than 0.2%. In nail hardeners, the restriction is more lenient as the EU permits up to 5.0% of formaldehyde . But products that contain more than 0.05% of formaldehyde in the finished state must carry a label that states that the product "contains formaldehyde."

The Cosmetic Industry in the United Sates reports that their resulting formulations comply with the US Food and Drug Administration's (FDA) requirements with regards to labeling, in cases where safety of the product has not been determined. In 1976, the Cosmetic, Toiletry and Fragrance Association (CTFA) established the Cosmetic Ingredients Review (CIR) with support of the US Food and Drug Administration and the Consumer Federation of America. The CIR's laboratory studies ingredients used in cosmetic formulations and issues safety assessments of these ingredients as either:
S: Safe in present practice of use and concentration
SQ: Safe with Qualifications
I: Insufficient data
U: Unsafe
Formaldehyde is rated "Safe with qualifications" by the CIR.

The following compounds in cosmetic formulations have been the subject of debates due to it's ability to function as preservatives while having the ability to release formaldehyde in very small amounts over time: Quaternium-15, imidazolidinyl urea and diazolidinyl urea. The cosmetic industry claims that low levels of these compounds are sufficient to retard micorbial growth while ensuring that the actual level of free formaldehyde released does not exceed the permissible maximum level of 0.2%. According to the CIR, Quaternium-15, a preservative and an antistatic agent; can be dermally absorbed but there are no known developmental effects that can occur when applied dermally. It is reported to be a dermal irritant only when present in more than 5.0% of the product's total composition. The allowable maximum concentration of this quaternary ammonium salt is 0.2% when used in cosmetics and personal care products. The maximum allowable concentration for diazolidinyl urea is 0.5% while the most commonly used preservative, imidazolidinyl urea can be used to a maximum concentration of 0.6%.

Should one choose to be cautious with cosmetics used for personal cleanliness or physical enhancements, the Cosmetic Ingredients Review presents a list of commonly used ingredients, its functions and their respective safety assessment ratings. Read labels in cosmetic packaging and identify the preservatives. Should the label indicate "contains formaldehyde," this means that the free formaldehyde released from the product exceeds 0.05%. Though this is not an exact indication of the potential for total free formaldehyde to exceed 0.2% during normal use of the product, stop using the product should dermal irritation occur.

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