Technical Report
Biological activity of fenitrothion and its degradation products
Miyamoto, J; Mikami, N; Mihara, K; Takimoto, Y; Kohda, H; Suzuki, H
PESTAB/79/0436
PESTAB. Derivatives of fenitrothion were prepared. These derivatives were oxidized at the 3-methyl group and included 3-hydroxy methyl fenitrothion and 3-formyl fenitrothion. The toxicity of these derivatives after ip dosing to experimental animals was higher than that of fenitrothion. The oxygen analogs were more toxic than fenitrooxon. The insecticidal activity, however, was much lower than that of fenitrothion. When S-methyl fenitrothion was tested in mice it was found to be less toxic that fenitrooxon. Fenitrothion proved more toxic than amino analogs of fenitrothion and fenitrooxon and their derivatives. All the degradation products were less toxic than fenitrothion to kilifish with the exception of 3-methyl- 4-aminophenol. In daphnia, fenitrothion and fenitrooxon were the most toxic. The fenitrothion derivatives exhibited no mutagenic activity in Salmonella typhimurium, with the exception of 3-hydroxy methyl fenitrothion. This was the case regardless of the presence of mammalian hepatic metabolizing enzymes.