Cypermethrin-Induced Changes in the Dehavioural, Morphometric, Haematological and Histological, Profiles in Mice Mus Musculus L.

Abstract

Cypermethrin, a synthetic pyrethroid insecticide having low mammalian toxicity, is a fast- acting neurotoxin and is known to cause free radical-mediated tissue damage. It is used worldwide for pest control in agriculture and households. The present study investigated the cypermethrin-induced clinical and behavioural symptoms, accompanied by morphometric, histological and haematological changes in the albino mice (Mus musculus L.) Twenty five adult male albino mice were divided equally into five groups where each 20g mice received: distilled water only (Group I, served as control); 0.10 ml cypermethrin (Group II); 0.15 ml cypermethrin (Group III); 0.20 ml cypermethrin (Group IV); and 0.25 ml cypermethrin (Group V). Treatments continued intraperitoneally each week for four consecutive weeks. During the experimental period, there were significant decreases between the initial and final body weights in the cypermethrin-treated mice but no abnormalities were observed in the control group. At the end of the 4th week, all the mice were sacrificed; their brain, lungs, heart, kidneys, liver, viscera and gonads were dissected out, weighed and preserved in 70% ethanol. The samples of liver and kidneys were processed for histological studies. Cypermethrin treatment exhibited severe histopathological changes especially in the liver and kidneys accompanied by weight loss of various organs. Cypermethrin-induced necrosis of various body parts, degeneration and necrosis of hepatic cells, dilatation of sinusoids and dissociated remark cordons in livers, sloughing off of epithelial cells, shrinkage of glomeruli, and necrosis of renal tubules in kidneys were noticeable. These changes were due presumably to the oxidative stress that modified biochemical parameters and histological aspects of liver and kidneys. Just before sacrifice, blood was collected from the experimental mice for the estimation of major haematological profiles. The results revealed statistically significant decrease in the red blood cells, platelets, haemoglobin, neutrophils and basophils but increase in the white blood cells such as lymphocytes, monocytes and eosinophils. It was observed from the present study that repeated exposure to cypermethrin affected the behavioural, morphometric, histopathological and haematological profiles of the albino mice. From these findings, it is postulated that cypermethrin and other synthetic pyrethroids might cause hazardous effects in mammals including human beings and therefore, judicious use of this insecticide should be assured while applying them at agricultural field and household purposes.