Abstract

Several fish samples from the Lagos lagoon, Nigeria were analyzed for the presence of polychlorinated biphenyls (PCBs). The fish species analyzed includeTilapia zilli (red belly Tilapia), Ethmalosa fimbriata (Bonga shad) and Chrysichthys nigrodigitatus (catfish). Eight PCB congeners were identified and quantified in muscle of the species analyzed. The concentration of total PCBs in samples ranged from 0.56 to 2.94 ppm. The study shows that concentrations of PCBs were higher in adult than in juvenile of most of the fish, and there was no correlation between fat content and total concentration of PCBs.  The concentration of PCBs found in fish samples in this study were above the WHO residual limit of 0.2 ppm. The concentration levels in this study were compared with the levels detected in other parts of the world. The study confirms PCBs persistence in Lagos Lagoon, despite its ban several decades ago.

Key words: PCBs, Lagos Lagoon, fish, gas chromatography (GC), persistent organic pollutants (POPs).