Evaluation of Polychlorinated Biphenyls in Sediments from Surface Waters of Igodan, Okunmo, Lebi, Idepe and OAUSTECH in Okitipupa, Ondo State Nigeria

Abstract

The presence of PCBs in water bodies is an emerging issue for water quality. This is because, once PCBs reach a lake or river, they concentrate in the sediments by attaching to the organic matter. Therefore, the objective of this paper is to evaluate the level of polychlorinated biphenyls (PCBs) in sediment from surface waters of Igodan, Okunmo, Lebi, Idepe and Oaustech in Okitipupa, Ondo State Nigeria using appropriate standard methods. Data obtained reveals that in Igodan the concentration of PCBs in sediment w.as PCB 44 (5.42±0.00), PCB 18 (3.04±0.00), PCB 28 (3.27±0.07) and PCB 170 (6.60±0.00). Okunmo PCBs concentration in sediment was PCB 44 (0.67±0.00), PCB 18 (0.03±0.00), PCB 28 (0.32±0.00) and PCB 170 (0.18±0.00). Lebi PCBs concentration in Sediment was PCB 44 (0.82±0.00), PCB 18 (3.96±0.00), PCB 28 (1.12±0.00) and PCB 170 (1.08±0.00). Except for PCB 170 (0.33±0.02), the PCB concentration in sediment from the Idepe and the OAUSTECH were both below the detection limit (BDL). Correlation between Physicochemical Parameters and PCBs homologs shows a negative correlation for the relationship of EC (Electrical Conductivity), TOC (Total Organic Carbon) and pH at ( -0.283), (-0.262) and ( -0.246) respectively. According to multivariate investigation, releases from nearby factories, deterioration of electrical cables and transformers, waste from university laboratories and facilities, as well as diesel residues from lister engines could be associated with the elevated levels of PCBs in sediments collected from the five sampled sites in Ondo State. TriPCBs > tetraPCBs were in this order in which the median concentrations of PCB homologues were found in sediments from the surface water.