Toxicity Assessment of Synthetic Pyrethroids (Lambda Cyhalothrin) on the Liver and Kidney Organs of Male Wistar Rats

Abstract

Aims: Humans and animals are occasionally and unintentionally exposed to lethal and sub lethal doses of pesticides stemming from its various uses to control pests both in agriculture, homes, gardens and public health. The use of pyrethroid products has grown and continues to grow due to the suspension of some organophosphorus and organochloride products. This current study evaluated the toxic effects of lambda-cyhalothrin (LCT) on hematological and histopathological changes in the liver and kidney organs of rats after sub chronic exposure. Study Design: Completely randomized design (CRD) with 5 treatments replicated 5 times. Place and Duration of Study: Department of Crop Protection and Environmental Biology, Faculty of Agriculture and Forestry, University of Ibadan, Nigeria, between July and August, 2015. Methodology: Twenty-five 7-week-old male Wistar rats were randomly assigned to five groups. The control (group 1) received distilled water, while experimental groups 2, 3, 4 and 5 received by gavage 25, 50, 75 and 100 mg/kg body weight, respectively LCT over a period of five weeks. Hematological and histopathological studies were carried out on the blood and organs of interest, respectively on termination of the experiment. Results: There was a dose-related reduction of white blood cell count from 3.25±0.22 (control) to 3.00±0.62 (100 mg/kg), and severity in alteration of the micro anatomy of the liver and kidney with increase in LCT concentration in the treated animals. The results showed necrosis and vacuolar changes in the hepatocytes and congestion of interstitial blood vessels. Also observed was a significant change in the body weight of the wistar rats after the 5th week of treatment with an average weight of 198 kg,196 kg, 194 kg, 186 kg, 160 kg for control, 25 mg/kg, 50 mg/kg, 75 mg/kg and 100 mg/kg treatment respectively. Conclusion: lambda-cyhalothrin is highly toxic (even at the lowest dose in this experiment) and may cause cell damage, organ failure, anaemic conditions and reduce immunity.