Baseline Levels of Polybrominated Diphenyl Ethers (PBDEs) in Water and Sediment from River Benue, North Central Nigeria

Abstract

Polybrominated diphenyl ethers (PBDEs) have been recognised as persistent organic pollutants (POPs) and are also among chemicals classified as endocrine-disrupting compounds (EDCs) which interfere with the endocrine system and disrupt the physiological function of hormones in animals and humans alike. This study determined the concentrations of six PBDE congeners (BDE 47, BDE 99, BDE 100, BDE 153, BDE 154 and BDE 183) in water and sediment samples from River Benue, in the Makurdi Metropolitan Area in North Central Nigeria using gas chromatogragh – mass spectrometer. These congeners are components of the pentaand octaBDE formulations that have been banned by the European Union. The samples were collected from the River, bimonthly, for one year across dry and wet seasons. All the congeners considered were found to be present in both water and sediment. The levels of Σ6PBDEs in water ranged from 0.02 – 0.11 ngL _1 during dry season and 0.10 – 0.76 ngL during wet season while the concentrations in sediment during dry and wet seasons ranged from 4.65 – 26.74 ngg and 4.40 – 17.15 ngg respectively. The percentage recoveries from solid phase and Soxhlet extractions ranged from 68 – 111 % and 71 – 109 % respectively. It was concluded that the presence of all the congeners in both water and sediment coupled with their established environmental persistence and bioaccumulation posed a pollution risk to the river which requires further monitoring and preventive measures to be taken. KeywordsGas chromatograph – mass spectrometer; polybrominated diphenyl ethers; sediment; river water; Nigeria