Impact of Polystyrene Exposure on Hepatorenal Responses in Male and Female Albino Wistar Rats

Abstract

Microplastics have become a major health concern because of its potential adverse influences on marine, wildlife and public health. In this study, pristine polystyrene and Styrofoam microplastics particles of diameter < 5mm were used to investigate the toxic effects of polystyrene microplastic (PS-MP) exposure on hepatic and renal function of male and female Wistar rats. The rats were divided into seven groups for both male and female, with one control group and six test groups each. The two forms of polystyrene microplastics were incorporated into the feed of the test groups in varying quantities (1, 5 and 10 % of the feed), and exposure lasted for a period of 90 days. Results showed that aspartate aminotransferase (AST), serum albumin (ALB), total bilirubin (TB), conjugated bilirubin (CB) were significantly (p < 0.05) decreased compared to control male and female rats. Histological analysis provided further insights, indicating that despite mild alterations in liver enzymes, albumin and total protein levels in specific test groups, microplastics did not compromise the structural integrity of hepatocytes in male and female rats. However, kidney function parameters exhibited significant (p < 0.05) increases in serum urea, creatinine, K+, and Cl- levels in test rats of both sexes compared to controls. Regardless of sex, the trends of elevated renal markers were similar. These findings suggest that exposure to polystyrene microplastics may adversely affects renal functional capacity even at low doses.