Final Report on the Safety Assessment of 2,4-Diaminophenoxyethanol Dihydrochloride

Abstract

2,4-Diaminophenoxyethanol Dihydrochloride (2,4-DAPE) is an aromatic amine that is used as a coupler in permanent (oxidative) hair dyes at concentrations up to 1.0%. 2,4-DAPE was slightly toxic in rats and mice. No significant adverse changes were observed in a subchronic toxicity test. 2,4-DAPE was practically nonirritating when a 4% aqueous solution was instilled into the conjunctival sacs of the eyes of rabbits. 2,4-DAPE was slightly irritating to the skin of rabbits when tested at a concentration of 4.0%. Based on animal studies, 2,4-DAPE was judged to produce low level sensitization in humans. Coal tar hair dyes, including those containing 2,4-DAPE, are exempt from the principal adulteration provision and the color additive provisions in Sections 601 and 706 of the Federal Food, Drug, and Cosmetic Act of 1938 when the label bears a caution statement and patch test instructions for determining whether the product causes skin irritation. No teratogenic effects were observed due to administration of 2,4-DAPE. No mutagenic activity attributable to 2,4-DAPE was observed in 22 mutagenic studies. However, in a few studies, a marginal mutagenic response was reported. In two oral carcinogenic studies, one in which mice were dosed with 0.04 and 0.07% 2,4-DAPE and the second in which rats were dosed with 0.05 and 1.0% 2,4-DAPE, no carcinogenic effects were produced. On the basis of the data presented in this report, it is concluded that 2,4-Diaminophenoxyethanol Dihydrochloride is safe as a cosmetic ingredient in the present practices of use and concentration.