10.22376/ijpbs.2019.10.1.p1-12 Volume 2 Issue 3 2011 (July - September) Environmental pollution is a growing concern and, more importantly, pollution of the aquatic ecosystem is alarming. Bivalves are commonly used as bio-indicators of marine pollution. In the present study the lessThan i greaterThan Perna viridis lessThan /i greaterThan was exposed to cadmium, copper, lead and zinc concentrations under longterm chronic toxicity for the estimation of biochemical biomarkers. Significant differences in TBARS levels and antioxidant enzyme activity were found. Higher levels of TBARS were found with cadmium exposure. This study suggests that TBARS levels and antioxidant enzymes activity are affected by biotic and abiotic factors and have potential as indicators of heavy metal contamination. Since these results were also found to vary, the determination of oxidative stress biomarkers in lessThan i greaterThan Perna viridis lessThan /i greaterThan may serve as a convenient approach during pollution biomonitoring programme. J.S.I Rajkumar And M.C John Milton Oxidative stress, antioxidants, reactive oxygen species, heavy metals, lipid peroxidation. 50-59