Carcinogenicity and Toxicity of Inhaled Nitrobenzene in B6C3F1 Mice and F344 and CD Rats

The potential carcinogenicity and toxicity of inhaled nitrobenzene were evaluated following chronic (2-year) exposure in mice and rats. Male and female B6C3F1 mice were exposed to 0, 5, 25, or 50 ppm nitrobenzene, while male and female F344 rats and male CD rats were exposed to 0, 1, 5, or 25 ppm nitrobenzene. All exposures were for 6 hr/day, 5 days/week excluding holidays, for a total of 505 days over 2 years. Survival was not adversely affected by nitrobenzene exposure, and only mild exposure-related decreases in body weights (