4-Nitroanthranilic acid, a nitrobenzene derivative formerly used as a dye intermediate, was selected for bioassay by the National Cancer Institute along with other dye intermediates in an attempt to identify those chemicals which may be responsible for the increased incidence of bladder cancer observed among workers in the dye manufacturing industry.
A bioassay of 4-nitroanthranilic acid for possible carcinogenicity was conducted using Fischer 344 rats and B6C3F1 mice. 4-Nitroanthranilic acid was administered in the feed, at either of two concentrations, to groups of 50 male and 50 female animals of each species. The high and low time-weighted average concentrations used for the chronic study were, respectively, 1.5 and 0.46 percent for rats and 1.0 and 0.46 percent for mice. After a 78-week period of chemical administration, the rats were observed for an additional period of up to 32 weeks and the mice for an additional period of up to 17 weeks. For rats 50 animals of each sex were placed on test as low dose controls and 25 animals of each sex were placed on test as high dose controls. For mice 50 animals of each sex were placed on test as controls for each dose group.
No statistically significant increases in tumor incidence were observed among rats or mice receiving diets containing 4-nitroanthranilic acid.
Under the conditions of this bioassay evidence was not provided for the carcinogenicity of 4-nitroanthranilic acid in Fischer 344 rats or B6C3F1 mice.