Genotoxicity of an organophosphorus insecticide, dimethoate, in the mouse.

The effects of dimethoate were investigated in the mouse after acute (10 mg/kg i.p.) or chronic treatment (0.6 ppm, 5 days a week for 7 weeks). Dominant lethal mutations were scored for a 7-week period after the acute dose, and immediately after exposure for the chronic dose. Chromosome damage was also analysed in bone marrow and spermatogonial cells at the same dose levels (from 12 to 48 h after treatment). MMS (60 mg/kg i.p.) was chosen as the positive control. In no experiment did dimethoate show any genotoxicity.