Comparative toxicity of malathion and its metabolite Alhpa-[O,O-Dimethyl phosphorodithio] propionic acid ethyl ester towards mice

ABSTRACT

The organophosphorus insecticide malathion [I] and its metabolite alpha-[O, O-dimethyl phosphorodithio] propionic acid ethyl ester [II] have been tested for their acute and subacute oral toxicity in mice. The oral LD50 values were determined to be 900 and 820 mg/kg, for malathion and its metabolite, respectively. Administration of both compounds to mice with one fifth and one tenth of their calculated oral LD50 for two weeks led to a significant depression of blood and brain cholinesterase activity in all treated groups. The maximum inhibition for brain cholinesterase activity [36-47%] and plasma [40-51%] was observed after 10 days of treatment. All treated mice returned to their normal statement after one week recovery period. Both compounds proved to have comparable toxicity towards mice