DEVELOPMENTAL TOXICITY OF THE SUBSTITUTED PHENYLUREA HERBICIDE ISOPROTURON IN RATS

Isoproturon, a substituted phenylurea herbicide, was studied for its t oxicity to darns and its potential fetotoxic/teratogenic effects in th e fetuses of albino rats. Isoproturon technical administered orally at 45, 90 or 180 mg/kg/d to darns during d 6-20 of pregnancy did not pro duce maternal toxicity at 45 or 90 mg/kg/d. However, 180 mg isoproturo n/kg/d caused changes in maternal enzymes and chromatid breaks. There was no fetotoxic/teratogenic effect of isoproturon at the tested dosag e levels in number of implantations, percent resorption, fetal weights , and external, visceral and skeletal fetal observations.