Polybrominated Diphenyl Ethers in Dust from the Vicinity of Power Generation Plants in Nigeria: Distribution, Risks Assessment and Source Apportionment

Abstract

Polybrominated diphenyl ethers (PBDEs) constitute a class of widespread environmental contaminants that pose significant health risks. Therefore, this study investigated the distribution, risks and sources of PBDEs in dusts from power generation plants in Nigeria. A total of 24 dust samples were collected from four power plants. Samples were collected for six months covering both wet and dry seasons. Dusts were extracted for PBDEs following the United State Environmental Protection Agency Method 3550C using a 1:1 mixture of dichloromethane and n-hexane. Thereafter, the extracts were cleaned-up and analyzed for PBDEs using a gas chromatograph-mass spectrometer. The results indicated that the mean concentrations of ∑39 PBDEs in the dusts ranged from 17.5 to 54.6 ng g-1 for wet season and 55.4 to 157 ng g-1 for dry season. There were significant spatio-temporal variations in the concentrations of PBDEs in the dust. The PBDEs have higher concentrations during the dry season than the wet season. The hazard index and total cancer risk values indicated that there is neither adverse non-carcinogenic risk nor carcinogenic risk from exposure to PBDEs in these dusts. Source apportionment indicated that the PBDEs in the dusts were from the use of deca- and penta-BDE commercial formulations used for dielectric insulating fluids for transformers, capacitors, cable insulators etc. It is hereby recommended that the Federal Ministry of Environment should establish environmental policy and enforceable regulatory frameworks for the control of PBDEs in order to minimize the levels environmental PBDEs and the risk to human and ecosystems.