Levels, Spatial and Seasonal Distribution of Polybrominated Diphenyl Ethers (PBDEs) in Water, Sediments and Sarotherodon melanotheron from Ologe Lagoon

Abstract

Polybrominated diphenyl ethers (PBDEs) are chemical additives of increasing concern in water bodies associated with industrial and urban areas. In this study, they were quantified in sediments, surface water and Black Chin Tilapia, Sarotherodon melanotheron from three sampling zones of Ologe Lagoon, Nigeria. The lagoon receives effluents and runoffs from the neighbouring industrial town of Agbara. Quantification of PBDE congeners in the samples was done using a gas chromatograph coupled electron capture detector (GC-ECD). Sediment ∑PBDEs levels of 0.05±0.006 to 0.09±0.006 ng/g were below Environment Canada’s (EC’s) safe limit (6124 ng/g) while levels in water ranged from 0.01±0.003 to 0.02±0.005 mg/L and were above EC’s safe limit (0.0002 mg/L). ∑PBDEs levels in the Tilapia ranged from 0.06±0.01 to 0.12±0.01 ng/g and were below EC’s safe limit (631 ng/g). There was no significant (P > 0.05) seasonal variation of ∑PBDEs concentrations in the assessed fish. The low levels of PBDEs in Sarotherodon melanotheron suggest that the fish are safe for consumption. However, there is a need for continuous efforts to improve industrial effluents treatment and manage urban surface run-offs into water bodies in order to avoid potentially catastrophic levels of PBDEs  in urban water bodies.