Screening of Blood Cholinesterase Level in Farmers to Evaluate the Level of Exposure to Pesticide Monocrotophos

IJEP 42(1): 65-70 : Vol. 42 Issue. 1 (January 2022)

N. Ramya, Sathish Shankar Bhat and P.K. Maheshwar*

 University of Mysore, Yuvaraja’s College, Department of Microbiology, Mysore – 570 005, Karnataka, India


Farmers handling pesticides without following the instructions or spraying them without any personal protective equipment are more prone to pesticide exposure. Monocrotophos is one of the extensively used as well as highly hazardous organophosphorus insecticides. It is known to inhibit the acetylcholinesterase enzyme, which plays an important role in the hydrolysis of the neurotransmitter acetylcholine at the cholinergic synapses. This research aims to calculate the cholinesterase level as a biomarker to compare the pesticide exposure level in the blood of farmers and a comparative variation in cholinesterase level before and after six months of pesticide exposure. The results indicated a considerable decrease in the cholinesterase levels in the blood serum of farmers after exposure to monocrotophos insecticide as compared to the non-exposure time. Percentage depression of cholinesterase is found to be high in young spray farmers. Statistical evaluation results (t=33.231) also confirmed depression in the cholinesterase level is highly significant. The p-value for the decrease in cholinesterase was found to be less than α=0.05, that is 0.009<0.05.


Monocrotophos, Blood sampling, Acetylcholinesterase, Cholinesterase, Pesticide


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