Ecological and Health Risk Assessment of Polychlorinated Biphenyls in Water and Sediments in Bodo Riverine Area, River State, Nigeria

Abstract

Concentrations of nine polychlorinated biphenyls (PCBs) were assessed in sediments and water in the Bodo River area, Gokana Local Government of River state Nigeria to assess the risk associated within the region due to the effect of oil spillage and marine pollution. The analytical procedure involved the application of Gas Chromatography coupled with mass spectrometric detection (GC/MS) for identification and quantification of and polychlorinated biphenyls respectively with high degree of accuracy and precision after triplicate analysis. All the selected PCB congeners analyzed were detected in the analyzed samples at different frequencies. The total concentrations of PCBs ranged from nd (not detected) to 4.15 mg/kg in sample A with an average concentration of 1.66 mg/kg, nd to 8.4 mg/kg in sample B with an average concentration of 3.25 mg/kg and nd to 7.30 mg/kg in sample C with an average concentration of 3.64 mg/kg in sediments. While the total concentrations of PCBs in the water sample ranged from nd (not detected) to 1.25 mg/kg in sample A with an average concentration of 0.56 mg/kg, nd to 4.50 mg/kg in sample B with an average concentration of 1.20 mg/kg and nd to 2.2 mg/kg in sample C with an average concentration of 0.88 mg/kg. Health risk assessment employed in this study includes the chronic daily intake and the carcinogenic risk via ingestion, inhalation and dermal contact using established guidelines. The total concentrations of PCBs were used to assess the cancer risk probabilities in humans via ingestion, dermal contact and inhalation of sediments particles. Very low cancer risk was found in all water samples compared to sediments samples caused by ƩPCBs. The results of the ecological risk assessment of PCBs in the Bodo River demonstrated the presence of PCBs in all sampling sites showing that the sites were highly contaminated with largely negative biological effects and a high potential risk to the environment.