Abstract
Disperse Black 9 is a monoazo dye used in hair dyes at a concentration not exceeding 0.4%. In acute toxicity studies, Disperse Black 9 was slightly toxic to practically nontoxic when administered orally and practically nontoxic when administered intraperitoneally. At a concentration of 100% the dye was nonirritating to rabbit eyes and was nonirritating to both the intact and abraded skin of rabbits at concentrations up to 0.38%. Disperse Black 9 at 25% did not produce either irritation or sensitization in guinea pigs. In subchronic oral studies Disperse Black 9 was toxic at 1% but not at 0.1 %. There were no signs of local or systemic toxicity at concentrations up to 0.24% in formulations. In chronic studies, dye containing 0.13% Disperse Black 9 was nontoxic to dogs. A hair dye formulation containing 0.5% Disperse Black 9 produced no significant toxicological effects when applied dermally to mice for 20 months. Disperse Black 9 (0.13% in a dye composite) produced neither teratogenic nor reproductive effects in rats or rabbits. Disperse Black 9 was nonmutagenic in four different assay systems. Disperse Black 9, 0.5% in a hair dye, was not carcinogenic when dermally applied to mice. A 3% suspension of the dye produced no irritation or sensitization in human subjects. On the basis of the available data, it is concluded that Disperse Black 9 is safe for use as a cosmeticingredient.
