2 Final Report on the Safety Assessment of p-Hydroxyanisole

Abstract

p-Hydroxyanisole is used as an antioxidant in cosmetic products at concentrations of up to 1.0 percent. The acute oral LD50 of p-Hydroxyanisole in rats was estimated as 1630 mg/kg. Undiluted p-Hydroxyanisole is a severe skin and ocular irritant in rabbits but produced minimal eye irritation at 0.1 percent and minimal rabbit skin irritation at 5 percent. Skin sensitization to p-Hydroxyanisole occurred when guinea pigs were treated at 0.5 M. p-Hydroxyanisole is a skin-depigmenting agent at concentrations approximating those used in cosmetic products. p-Hydroxyanisole was nonmutagenic in the Ames assay. No local toxic changes or tumors were observed following long-term application of 5 and 10 percent p-Hydroxyanisole. The antioxidant was inactive as a tumor promoter. Solutions of p-Hydroxyanisole produced embryotoxicity but not teratogenicity. The function of p-Hydroxyanisole in cosmetics is that of an antioxidant; it is not intended for use as a skin lightener or skin-depigmenting agent. Because of the depigmenting action of p-Hydroxyanisole in black guinea pigs at reported concentrations approaching those used in cosmetics, it is concluded that p-Hydroxyanisole is unsafe for use as a cosmetic ingredient.