Oxidative Stress Biomarkers (superoxide Dismutase and Glutathione) of Exposure to Bisphenol-a in the Fresh Water Fish, Clarias Gariepinus

Bisphenol A (BPA), a synthetic compound frequently used in the production of polycarbonate plastics, epoxy resins, and other consumer goods, is a well-known EDC due to its estrogen-like properties. The aim of this study was to evaluate the oxidative stress induced by Bisphenol A (BPA) exposure in Clarias gariepinus using superoxide dismutase (SOD) and glutathione (GSH) as biomarkers. Following the organization for economic cooperation and development (OECD) guidelines for sublethal testing, fish were exposed to four BPA concentrations (1.25, 2.50, 5.0, and 10.0 mg/L) alongside positive (0.0 mg/L BPA) and negative (1.25 mg/L DMSO) controls under static conditions for 28 days. Superoxide dismutase and glutathione levels were quantified spectrophotometrically, with statistical analysis performed via one-way ANOVA and Dunnett’s test (p < 0.05). Over 14, 21, and 28 days, superoxide dismutase activity decreased significantly at higher BPA concentrations (5.0 and 10 mg/L), indicating the inability of antioxidant defense systems to cope with prolonged oxidative stress. While glutathione levels began to exhibit a dose-dependent increase at higher BPA concentrations (5.0 and 10 mg/L). The significant decline in superoxide dismutase and glutathione levels at higher BPA concentrations observed in this study underscores the role of oxidative stress as a primary mechanism of bisphenol A toxicity. The prolonged exposure to bisphenol A likely overwhelms the antioxidant defense system, and can lead to oxidative damage and potential adverse effects on fish health, including lipid peroxidation and DNA damage.