Evaluation of the potential Toxicity and Interaction of Methomyl and Diazinon Insecticides in Male Rats

The toxic effect of methomyl and/or diazinon given orally to male rats for 4 consecutive days at the level of 20% of their LD50, was investigated. Methomyl did not affect plasma choline esterase (Ch E) after four days of treatment. Serum testosterone, lactate dehydrogenase (LDH), gamma glutamyl transferase (gamma G T) were decreased, while bilirubin alkaline phosphatase (ALP) and uric acid were increased. Serum creatinine phosphokinase (CPK) was increased significantly while creatinine was not affected. Diazinon caused substantial decline in plasma Ch E activity after four days of treatment. Serum creatinine phosphokinase and testosterone were altered significantly while lactate dehydrogenase and creatinine levels were comparable to controls. Serum bilirubin, ALP and uric acid were increased while gamma G T was decreased. Co administration of the two insecticides lowered plasma Ch E activity more than diazinon did. The combined effect on CPK, ALP, testosterone, bilirubin and uric acid was greater than that produced from each insecticide acting independently