The aim of the study was to evaluate the assessment of oxidative stress induced by fluoride which causes adverse effect in aquatic ecosystems like other pollutants. Study has been carried out on certain biomarkers in brain of cat fish (Heteropneustis fossilis). Biomarkers selected for stress monitoring were Lipid peroxidation (LPO) and antioxidant defense system enzymes, mainly Catalase (CAT), Superoxide dismutase (SOD), Reduced glutathione (GSH), Glutathione peroxidise (GPx) and Glutathione S-Transferase (GST) activities in brain of fish exposed to 35 mg F/L and 70 mg F/L of water for 45 days. Oxidative stress due to exposure to fluoride was observed in brain of cat fish and it was evident by the increased in LPO, GST level and decreased level of CAT, GSH, SOD and GPx levels in the brain tissues. Oxidative and antioxidant profiles indicate that chronic exposure to the fluoride is capable of inducing oxidative stress in fish.
