Mutagenicity screening of five methyl carbamate insecticides and their nitroso derivatives using mutants of Salmonella typhimurium LT2.

The mutagenic activity of five methyl carbamate insecticides-carbaryl, baygon, BUX-Ten, landrin and methomyl-and their nitroso derivatives were investigated using histidine auxotrophs-his TA98, his TA100, his TA1535, his TA1537 and his TA1538--of Salmonella typhimurium LT2 derived by Ames. The methyl carbamate insecticides did not cause a signficant increase in the number of revertant colonies in any of the strains used. In contrast, the nitroso derivatives of the carbamate insecticides greatly increased the number of colonies on plates inoculated with strains his TA100 and his TA1535. We conclude that the nitroso derivatives of the tested methyl carbamate insecticides are potent mutagens; whereas, the parent insecticides are non-mutagenic.