Investigating the effects of exposure to commonly used insecticides and mosquito repellents on Murine lungs, liver and kidney tissues

Abstract

Cypermethrin, a synthetic pyrethroid, has broad- spectrum use in agriculture, domestic and veterinary applications due to its high bioefficacy, enhanced stability and considerably low mammalian toxicity. The objective of this study was to investigate the histological changes in murine liver, kidney and lung tissues exposed to commonly used insecticides and mosquito repellents which main ingredients are cyprmethrin. Three groups of mice (six mice per group) were evaluated thus: a control group, a group exposed to the insecticide Killit spray, and a group exposed to Mortein Doom. The control group displayed no significant histological changes in any of the three organs, indicating that the experimental conditions did not inherently cause tissue damage in the group. Both treatment groups showed no significant lesions in lung tissues, suggesting that at the exposure levels used, the insecticides did not adversely affect the lungs. Among the group exposed to Killit, 83.3% of the mice exhibited kidney lesions characterized by hydropic and vacuolar degeneration, indicating acute nephrotoxicity. Additionally, 33.3% of the mice exposed to Kilit had mild to moderate fatty changes in the liver. The difference in the occurrence of kidney lesions in the group exposed to Kilit and control group was statistically significant (p = 0.003 at 95% CI). On the other hand, majority (80%) of the mice exposed to Mortein Doom had liver lesions, especially multifocal hepatitis and fatty change, pointing to a stronger hepatotoxic effect of the product. Furthermore, 50% of the mice in this group had kidney lesions, indicative of potential metabolic disruptions. In conclusion the two insecticides had no histopathologic effect on lung tissues, both Killit and Mortein Doom caused significant acute toxicity in the kidneys and livers of the exposed mice. These findings underscores the need for further study on the chronic effects of these insecticides and advocates for the development of safer alternatives to minimize health risks.