Abstract
Dimethoate (0, 0- dimethyl-S- (N- methylcarbamoyl- methyl) phosphorodithioate), an organophosphate insecticide, was examined for its potential to produce developmental toxicity in rats after oral administration. Pregnant Fischer 344 rats were given sublethal doses of 0 (corn oil), 7, 15, and 30 mg/kg/day dimethoate by garage on Gestation Days 6 through 15. Maternal effects in the 30 mg/kg/day dose group included cholinergic signs, decreased body weight, and decreased feed consumption. No maternal effects were apparent in the 7 and 15 mg/kg/d dose groups. Maternal exposure to dimethoate during organogenesis significantly . affected the number of live fetuses, early resorption, mean fetal weight, and the incidence of skeletal malformations in the 30 mg/kg/d dose group. On the basis of the present results dimethoate showed maternal and developmental toxicity at 30 mg/kg/clay.
