Characterisation of Polychlorinated Biphenyls in Coastal Inland Seawater, Nigeria

The concentrations of polychlorinated biphenyls (PCBs) were determined in samples of surface seawater collected from five (5) different locations along the coastline of a tropical lagoon. The surface water samples were analysed using gas chromatography coupled with electron capture detector (GC-ECD) with fifteen (15) PCB congeners detected across the studied area. The chlorobiphenyls levels are in the order Ebute Ero > Oko Baba > Ijora > Lagos Island > Unilag lagoon front with levels 107.89, 53.15, 34.90, 27.78, and 2.15 mg/L, respectively. The enhanced average concentration of PCBs at the Ebute Ero site is due to the predominance of PCB-180 and PCB-185. A negative correlation was found between the total PCB concentration and the level of dissolved oxygen. Although, the results indicated fairly high levels of PCBs, the anthropogenic contributions from industrial releases and domestic activities may be largely associated with the detected concentrations of the di-, tetra-, penta-, hexa-, hepta-, and octa-chlorobiphenyls. (paper)