Antioxidant responses to benzo[a]pyrene and Aroclor 1254 exposure in the green-lipped mussel, Perna viridis

In this study, the green-lipped mussel, Perna viridis (L.), was exposed to two concentrations of benzo[a]pyrene (B[a]P) (0.3 μg l^-1; 3 μg l^-1) and two concentrations of Aroclor 1254 (0.5 μg l ^-1; 5 μg l^-1). In addition, a mixture of the contaminants was used (0.3 μg l^-1 B[a]P+0.5 μg l^-1 Aroclor 1254; 3 μg l^-1 B[a]P+5 μg l^-1 Aroclor 1254). All concentrations were nominal. A suite of enzymes [glutathione S transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR)], glutathione (GSH) level and lipid peroxidation (LPO) in the mussel gill and hepatopancreas were monitored over 18 days. CAT and GSH in gill tissue were positively correlated with concentration of Aroclor 1254. Activity of hepatic GST and SOD was significantly related to body burden of Aroclor 1254. LPO, GR and GPx in gill and hepatopancreas and hepatic GST were positively correlated with B[a]P concentration. The results indicate the importance of using biomarkers specific to the type of contaminant(s) that are likely to be present. Controlled laboratory experiments, such as this study, are useful in ascertaining biomarkers suitable for use with complex contaminant mixtures in the marine environment.