Ecological and Human Health of Polychlorinated Biphenyls (PCBs) Across Tide and Saline Influenced Hydrocarbon Mining Zones of Tropical Deltaic Wetlands, Southern Nigeria

Polychlorinated Biphenyls (PCBs) concentrations across the Lower Orashi and Sombriero which are tide and saline influenced were measured across eight (8) locations. These unique environments are affected by hydrocarbon mining especially in the Tropical Deltaic Wetland zones. Sediment and water samples were analyzed to ascertain potential human and ecological implications. Standard laboratory methods were adopted for physico-chemical parameters of water while PCB sequencing/speciation was done by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The PCB speciation chemistry reveals non-similarity in their characteristic bioabundance across all stations. However, similarity exists in PCBs concentrations in the marine media. PCBwater locational dominance is in the order: SR3 (104.02) > TZ2 (5.16) > SR2 (3.60) > TZ1 (3.35) > OR3 (3.04) > OR2 (2.91) > SRI (2.39) > OR1 (1.38). ∑PCBwater (125.85) > ∑PCBsediment (47.02), implying the surface waters bioaccumulates more PCBs than sediments comparatively. PCB-66 2,3’,4,4’- Tetrachlorobiphenyl (5.13) ranks the highest ecotoxin in the study area. SR3 and OR1 ranks highest and least in PCBs locational concentrations respectively. Ecologically, Sombriero River (SR = 110.01, %) > Transition Zone (TZ = 8.51, %) > Orashi River (OR = 7.33, %) in PCB bioabundance, indicating locational and media variations at P < 0.05. The results show riparian populations’ exposure to PCBs posing likely health impacts. Review, monitoring and stringent enforcement of importation, application, disposal regulations of PCB laden equipment and appliances is recommended amongst others.