Human exposure to nitrotoluenes can occur during their production and use, although few data are available. Nitrotoluenes have been detected in effluents from the manufacture or use of nitrotoluenes and in surface and groundwater. No data were available to the Working Group. Rare mesotheliomas of the tunica vaginalis were reported in male rats receiving 2-nitrotoluene in the diet for 13 weeks. No relevant data on absorption, distribution, metabolism or excretion in humans were available to the Working Group.
Urinary elimination is the major route of excretion in rats exposed to nitrotoluene isomers.
Male rats excrete more of an administered dose of nitrotoluene in the bile compared with female rats. Liver toxicity was observed in rats exposed to 2-nitrotoluene. In mice, the only evidence of toxicity was degeneration and metaplasia of the olfactory epithelium. All three isomers impaired testicular function and increased the length of the oestrus cycle. The 2-isomer decreased sperm motility in mice.