Effect of the Pesticide, Malathion on Non-Target Organism, Earthworm Lampito mauritii

Malathion, a pesticide in the organophosphate chemical family is the most commonly used pesticide in our country. Symptoms of exposure to malathion include headache, nausea, vomiting, burning in eyes, difficulty in breathing and lethargy. Earthworms have been used as biomarkers for assessing chemical environmental pollution. Due to their low cost, easy handling, their direct body contact with the soil and ethical issues related to mammalian studies, earthworms were chosen for the present study. Three doses of malathion 150, 300 and 600 mg/kg soil were used as treated soil. The effect of application of malathion on the earthworm Lampito mauritii was studied for 5, 10, 15 and 30 days exposure by evaluating the body weight, number of cocoons laid and the hatching efficiency of the cocoons. The results showed that there is a direct dose response relationship with respect to both, the concentration and time of application of malathion. The results have been statistically analysed.