Final Report on the Safety Assessment of Sodium m-Nitrobenzenesulfonate

Abstract

Sodium m-Nitrobenzenesulfonateis a water-soluble ingredient that is used as a chemical additive in hair dyes and colors and has been used as a base component in semipermanent hair coloring products. Product formulation data submitted to the Food and Drug Administration in 1994 indicated that this ingredient was used in 25 products, all of which were hair dyes and colors. In an acute oral toxicity study involving rats, the median lethal dose was not achieved at a dose of 5,000 mg/kg Sodium m-Nitrobenzenesulfonate. The results of a chronic oral toxicity study of a composite hair dye formulation containing 2.25% Sodium m-Nitrobenzenesulfonate indicated neither gross nor microscopic changes in beagle dogs that were related to test substance administration. The same hair dye formulation (administered in the diet at concentrations of 0.005% and 0.02%) was not classified as a reproductive toxicant in studies involving rats and rabbits. Moderate ocular irritation and mild skin irritation reactions to Sodium m-Nitrobenzenesulfonate were observed in rabbits. Based on these data, however, the safety of use of Sodium m-Nitrobenzenesulfonate in cosmetic products cannot be documented and substantiated. Additional safety test data are needed, including (1) purity and impurity data; (2) a 28-day dermal toxicity study and, if positive, then dermal absorption and distribution data in animals; (3) significantly absorbed, two different genotoxicity assays (one using a mammalian system) and, if positive, a dermal carcinogenicity study using National Toxicology Program methods; and (4) ocular irritation data in animals (if available). The currently available data are insufficient to support the safety of Sodium m-Nitrobenzenesulfonate as used in cosmetic products.