For definition of Groups, see Preamble Evaluation.
VOL.: 65 (1996) (p. 263)
Chem. Abstr. No.: 1-Chloro-2-nitrobenzene
Chem. Abstr. No.: 1-Chloro-3-nitrobenzene
Chem. Abstr. No.: 1-Chloro-4-nitrobenzene
The urinary metabolites of 4-chloronitrobenzene are qualitatively similar in humans and rats.
No data concerning the absorption, distribution, metabolism and excretion or toxic effects of 2- or 3-chloronitrobenzene in humans were available to the Working Group.
The disposition of 2-chloronitrobenzene in rats is similar to that of 4-chloronitrobenzene.
In humans, exposure to 4-chloronitrobenzene is associated with such symptoms as headache, palpitation, dizziness, nausea, vomiting and poor appetite. Cyanosis, methaemoglobinaemia and anaemia also occur. Methaemoglobinaemia and anaemia occur in rats exposed to 4-chloronitrobenzene, 3- chloronitrobenzene or 2- chloronitrobenzene.
In a single study in rats, a maternally toxic dose of 4-chloronitrobenzene increased the resorption rate and the frequency of skeletal malformations. In female rats and mice, inhalation exposure to 4-chloronitrobenzene increased the oestrus cycle length. In rats, but not mice, inhalation exposure to the compound decreased spermatogenesis with atrophy of the seminiferous tubules. In a continuous breeding study, a progressive decrease in fertility was noted in mice receiving 4-chloronitrobenzene.
In rats and mice exposed to 2-chloronitrobenzene by inhalation, decreased spermatogenesis was observed. No significant change was observed in exposed females. In a continuous breeding study, fertility was not affected in mice receiving 2-chloronitrobenzene.
2-Chloronitrobenzene induced reverse mutations but not primary DNA damage in bacteria. It was not mutagenic to insects. In mammalian cells in vitro, it induced sister chromatid exchange and chromosomal aberrations. Intraperitoneal injection into mice resulted in DNA damage in the liver, kidney and brain.
3-Chloronitrobenzene gave negative results in bacterial mutagenicity assays and in cultured mammalian cell chromosomal assays.
4-Chloronitrobenzene induced reverse mutations but not primary DNA damage in bacteria. It was not mutagenic to insects. At toxic doses, it induced chromosomal aberrations, sister chromatid exchange and repairable DNA breaks in cultured mammalian cells. Intraperitoneal injection into mice induced DNA damage in the liver, kidney and brain.
There is inadequate evidence in experimental animals for the carcinogenicity of chloronitrobenzenes.
For definition of the italicized terms, see Preamble Evaluation
See Also: Toxicological Abbreviations