Polychlorinated Biphenyls Contamination of Drinking Water Source of the Pra River: Congener Distribution and Associated Risk

PCB pollution of the environment and the associated ecological and health impacts have been of great concern since the 1970s, yet PCBs persist in the environment.In this study, the spatial distribution and impacts of PCBs at twenty different locations in the drinking water source of the Pra River in Ghana were determined in the wet and dry seasons.Extraction of PCBs was performed using solid-phase extraction and a solvent extraction system, respectively, and the analytes were identified and quantified by gas chromatography.PCBs 18, 153, and 180 were the dominant congeners in the river water.The mean 12 PCBs concentration ranges in the wet season were 0.04 -11 ng/L, 0.33 -69 ng/g, and 0.72 -153 ng/L.The dry season PCB concentrations were higher at all locations.The Pra River has low levels of PCB pollution at all the sites compared with other regions.In general, the hexa-chlorinated PCBs biphenyls were the most dominant homologue.The estimated probabilistic PCB cancer risk is much lower than the acceptable risk of one chance in a million (1.0E-06) of exposed persons to suffer the risk of cancer.The mean TEQs for fish, birds and humans/mammals were very low, and none of the samples exceeded the environmental quality standard of 1.0 pg-TEQ/L.The PCB concentration suggests that the river water does not pose a danger to aquatic organisms and human health.