DNA Damage and Oxidative Stress in Marine Gastropod Morula granulata Exposed to Phenanthrene

DNA damage and oxidative stress in marine gastropod Morula granulata was measured after in vivo exposure to four different concentrations (10, 25, 50, and 100 μg/L) of phenanthrene. Comet assay was used for measurement of DNA damage, whereas oxidative stress was assessed using a battery of biomarkers such as glutathione-S-transferase (GST), catalase (CAT), and lipid peroxidation (LPO). Our data showed concentration-dependent increase in percentage DNA in tail (TDNA), LPO, and GST activity in gastropods exposed to phenanthrene. CAT activity in gastropods was not found to be consistent with the phenanthrene concentrations. Significant increase in TDNA was observed at all concentrations above 10 μg/L of phenanthrene. Positive correlations were observed among oxidative stress biomarker and TDNA. Integrated biomarker response (IBR) analysis showed that among the four biomarkers, LPO and DNA damage (TDNA) were the most sensitive in response to phenanthrene exposure. Our results clearly showed that phenanthrene is genotoxic to gastropods and also causes oxidative stress.