Polychlorinated biphenyl accumulation and hepatic EROD activity in golden grey mullet Liza aurata from Tunis Bay, southern Mediterranean
AbstractLiza aurata was used as a bioindicator species to monitor contamination by organic xenobiotics of estuarine water at the outlet of Khélij channel [canal], Tunisia, from November 2002 to December 2003. Polychlorinated biphenyl (PCB) concentrations, including coplanar congeners, were measured in mullet muscle tissue. Mean PCB concentrations ranged between 77 and 180 ng g–1 wet weight. The PCB profiles were dominated by hexachlorobiphenyl congeners accounting for 25–52% of the total profiles. Total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents of coplanar PCBs, including mono- and non-ortho congeners, was 4 pg g–1 wet weight in December 2003 vs 82 pg g–1 wet weight in April 2003. Biological effects in mullet were evaluated by measuring ethoxyresorufin-o-deethylase (EROD) activity in fish liver. EROD activity was significantly elevated, compared to baseline values in control fish (43 ± 23 pmol min–1 mg–1 protein). The highest enzymatic activity of 1 202 ± 813 pmol min–1 mg–1 protein was recorded in July 2003.
Keywords: bioindicator, biomarker, pollution assessment
African Journal of Aquatic Science 2011, 36(2): 159–165