Occurrence and risks of polychlorinated biphenyls in water, sediment, and fish of Wupa River, Nigeria

The occurrence and risks of polychlorinated biphenyls (PCBs) in water, sediment, and fish from the Wupa River, Nigeria, were assessed in this study. Water, sediment, and fish were collected from five locations in the Wupa River in November 2019. After extraction with dichloromethane, hexane, and acetone, the PCBs were determined using gas chromatography equipped with a quadrupole mass spectrometer. The hazard index and total cancer risk models were used for risk evaluation of the detected PCBs. The results of this study show that the ∑28 PCB concentrations in the water, sediment, and fish ranged from 0.04-11.42 ng/L, 5032-10132 ng/g, and 64-4254 ng/g, respectively. The hazard index values for children and adults were generally > 1, suggesting a potential non-carcinogenic risk for humans exposed to PCBs from the river. However, the total cancer risk values were above 1 × 10-6 and indicated that there is a carcinogenic risk for humans exposed to the PCBs from Wupa River