Teratogenic potential of carbaryl given to rabbits and mice by gavage or by dietary inclusion.

The teratogenic potential of the insecticide carbaryl (1-naphthyl methylcarbamate) was evaluated in New Zealand rabbits and CF-1 mice. Rabbits were given 150 or 200 mg carbaryl/kg/day by gavage from Days 6 through 18 of gestation. Mice were given 100 or 150 mg carbaryl/kg/day by gavage or were given a diet containing 5660 ppm of carbaryl (1166 mg carbaryl/kg body wt/day) from Days 6 through 15 of gestation. An increased incidence of omphalocele was observed among the offspring of rabbits given 200 mg carbaryl/kg/day, which was a maternally toxic dose, and another case was observed among the offspring of rabbits given 150 mg/kg/day, a dosage which produced mild maternal toxicity. In comparison, carbaryl was not teratogenic in mice given maternally toxic doses of the compound either by gavage or by dietary inclusion.