Acute and subchronic oral toxicity of technical quinalphos in rats

The organophosphate insecticide quinalphos is extensively used in agriculture. Information on the mammalian toxicity of quinalphos is limited. The acute po LD50 of technical quinalphos was 19.95 mg/kg in males and 13.78 mg/kg in female rats. Administration of 0.75, 1.50 or 3.0 mg/kg/d technical quinalphos for 90 d po to rats produced poisoning and death. Male rats were more susceptible to quinalphos than female rats in the subchronic toxicity studies based on mortality, enzyme profiles and cholinesterase inhibition.