Expert Panel for Cosmetic Ingredient Safety:
The safety of these six ingredients has been assessed by the Expert Panel for Cosmetic Ingredient Safety. The Expert Panel evaluated the scientific data and concluded that 6-amino-m-cresol, 4-amino-m-cresol, 5-amino-4-chloro-o-cresol, and 5-amino-6-chloro-o-cresol were safe as used in oxidative and nonoxidative (semipermanent) hair dyes. The available data also supported the safety of 6-amino-o-cresol and 4-chloro-2-aminophenol for use in oxidative hair dyes, but were insufficient to determine the safety of 6-amino-o-cresol and 4-chloro-2-aminophenol in nonoxidative (semipermanent) hair dyes.
To supplement the safety test data on these ingredients, available data on related ingredients (4-amino-2-hydroxytoluene and p-, m-, and o-aminophenol) previously found safe as used by the Expert Panel were summarized. Percutaneous penetration of 5-amino-4-chloro-o-cresol and 5-amino-6-chloro-o-cresol alone was significant, but when combined with oxidative developer, skin absorption was extremely low. Both of these dyes were excreted rapidly via the urine. Repeated exposure of skin to 5-amino-4-chloro-o-cresol and 5-amino-6-chloro-o-cresol failed to produce any cumulative irritation and single exposures up to 10% were not irritating to skin. 5-amino-4-chloro-o-cresol and 5-amino-6-chloro-o-cresol combined with oxidizer were not sensitizers in maximization tests. Ocular irritation resulted from exposure to undiluted 5-amino-4-chloro-o-cresol, but not from exposure to a 5% solution. Only minor irritation was observed with 5% 5-amino-6-chloro-o-cresol. Sub chronic toxicity testing using 5-amino-4-chloro-o-cresol, 5-amino-6-chloro-o-cresol and 4-amino-m-cresol did not yield any adverse reactions. 6-amino-m-cresol and 4-amino-m-cresol were not mutagenic in tests. Exposure to 5-amino-4-chloro-o-aresol, 5-amino-6-chloro-o-cresol, 6-amino-m-cresol and 4-amino-m-cresol from hair dye products were several orders of magnitude below developmental toxicity no-observed-adverse-effect levels (NOAELs).
The available test data, coupled with patch test instructions, supports the safety of these ingredients in oxidative hair dyes. However, all of the data necessary to complete the review of 6-amino-o-cresol and 4-chloro-2-aminophenol in semipermanent hair dyes was not available. The Expert Panel was especially interested in more data on the metabolism of these ingredients. If metabolism was found to be similar to previously reviewed ingredients, additional data would not be necessary.
More information about the safety of hair dyes.
4-Amino-m-cresol and its salts are listed in the Cosmetics Directive of the European Union (see Annex III) and may be used as oxidizing coloring agents for hair dyeing at a maximum concentration of 3.0%, and a maximum concentration of 1.5% when mixed with hydrogen peroxide. 6-Amino-o-cresol and its salts and 4-chloro-2-aminophenol are not permitted for use in hair dye products marketed in Europe (see Annex II). 6-Amino-m-cresol, 5-amino-4-chloro-o-cresol and 5-amino-6-chloro-o-cresol are not specifically listed in the Cosmetics Directive.