Effects of Exposure to Selected Agricultural Pesticides on Liver Functions of Wistar Albino Rats

Abstract

Agricultural pesticides are widely used to improve crop protection and productivity; however, exposure to these chemicals may adversely affect non-target organisms. The liver plays a central role in xenobiotic metabolism and detoxification and is therefore particularly susceptible to pesticide-induced biochemical and structural alterations. This study investigated the effects of selected agricultural pesticides (Paraquat, Glyphosate ammonium, Nicosulfuron, 2,4-dimethylamine and Cypermethrin) on liver function, antioxidant status and tissue architecture in male Wistar albino rats. Forty-two (42) rats were randomly distributed into six groups of seven animals each and exposed to the pesticides for 14 days. The animals in the Cypermethrin-treated group (Group 6) died during the experimental period. At the end of the exposure period, blood samples were collected for biochemical analysis, while liver and lung tissues were examined histologically. Liver function results showed increases in ALT, AST and ALP activities and total bilirubin concentration in the pesticide-treated groups compared with the control. ALT increased by 40.25%, 37.83%, 42.22% and 81.56% in the Paraquat, Glyphosate ammonium, Nicosulfuron and 2,4-dimethylamine groups, respectively, with the highest value recorded in the 2,4-dimethylamine group (308.24 ± 10.54 U/L). AST showed increases of 148.98%, 279.11%, 123.29% and 245.26%, respectively, with the highest activity in the Glyphosate ammonium group (31.58 ± 2.96 U/L). ALP increased by 6.52%, 13.59%, 71.61% and 57.78%, respectively, with the highest value in the Nicosulfuron group (182.80 ± 4.07 U/L). Total bilirubin increased by 123.74–127.85% in the Paraquat and Glyphosate ammonium groups. Total protein decreased by 19.43–32.54%, while globulin decreased by 64.81–82.78% across the treated groups. Hepatic antioxidant indices were also altered. SOD increased by 35.81–209.51%, while CAT decreased by 7.28–48.80% in the treated groups. Hepatic GPX increased markedly by 609.50% in the Nicosulfuron group and 306.95% in the 2,4-dimethylamine group. Pulmonary MDA increased by 128.06%, 53.96% and 151.80% in the Glyphosate ammonium, Nicosulfuron and 2,4-dimethylamine groups, respectively, indicating increased lipid peroxidation. Histological examination revealed mild liver alterations, including sinusoidal and vascular dilation and inflammatory cellular infiltration, while lung sections showed alveolar and interalveolar septal thickening with inflammatory infiltration. Overall, the findings demonstrate that exposure to the selected pesticides caused dose- and pesticide-related biochemical, oxidative and histopathological alterations in the liver and lungs, while Cypermethrin exposure was associated with mortality during the experimental period.