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The Impact of Junk Science on R&D: A Review of the 'Dirty Dozen'
By: David C. Steinberg, Steinberg & Associates
Posted: September 29, 2010, from the October 2010 issue of Cosmetics & Toiletries.
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Replacement ingredients: When a fat or vegetable oil is oxidized, i.e. turns rancid, it produces an unpleasant odor. Therefore, antioxidants are used to prevent unsaturated compounds from oxidizing. Alternative antioxidants to BHA and BHT include propyl gallate and tert-butylhydroquinone (TBHQ). Tocopherol, also known as vitamin E, is another option that would be considered the natural alternative. It is a brownish colored liquid used typically at 1.0% to achieve the same efficacy as 0.02% of BHT. In most cases, this material is used in products so that vitamin E can be used on the label, although the word tocopherol must be used in the ingredient disclosure.
Coal Tar Dyes
The foundation also cautions consumers to look for p-phenylenediamine or colors identified as “C.I.” followed by a 5-digit number. According to the group: phenylenediamine, used in hair dyes, has been found to be carcinogenic in laboratory tests conducted by the US National Cancer Institute and National Toxicology Program. Other coal tar-derived colors are used extensively in cosmetics, identified by a five-digit Color Index (CI) number. The US color name may also be listed (“FD&C” or “D&C” followed by a color name and number). Coal tar itself is recognized as a human carcinogen and the main concern with coal tar colors are their potential as carcinogens. As well, colors may be contaminated with low levels of heavy metals and some contain aluminum (a neurotoxin). This is of particular concern when used in cosmetics that may be ingested, like lipstick.
Facts: As most chemists know, p designates para, which is different from m or meta; thus materials designated by p and m are different chemicals. p-phenlyenediamine is permitted in the European Union (EU) whereas m-phenylenediamine is prohibited, and it is p-phenylenediamine that is used as a precursor for hair dyes. In addition, p-phenylenediamine was reviewed by the CIR, which concluded that p-phenylenediamine, p-phenylenediamine HCI and p-phenylenediamine sulfate are safe for use as hair dyes based on the practices of use and concentration described in the safety assessment.4 The material also has been reviewed by the EU’s safety committee and added to Annex III of the EU Cosmetic Directive as being safe at up to 2% total, i.e. for both components of the hair dye process mixed, with the required warnings and directions. Based on FDA numbers, the total registered formulations containing p-phenylenediamine number 1,780.
Regarding CI numbers, the EU uses the letters CI followed by a 5-digit number as its nomenclature for colors. There currently are 144 colors with CI numbers approved for use in cosmetics in the EU. There are also 11 colors identified by name. It should be noted that chemicals having CI numbers are not necessarily allowed for use as colorants in cosmetics. The two critical ones are mica and tin oxide. Although they can be identified by CI numbers, these materials are not approved as colorants for cosmetics and may therefore not be listed in the “may contain” section of the product ingredient declaration.
In the United States, the names of colors are assigned by the FDA. Whereas the CI system assigns a different number to each shade of iron oxide black, yellow, red and brown, the FDA calls them all iron oxides. Like the EU, the FDA allows the dual labeling of colors, so both the FDA color name and CI number often appear on product labels; i.e., Blue 1 (CI 42090) or CI 42090 (Blue 1).