Polybrominated diphenylethers in sediments and biota downstream of potential sources in the UK

In a pilot survey, samples of sediment and fish tissue have been collected in the vicinity and downstream of suspected sources of brominated flame retardant compounds. These have been analysed for polybrominated diphenylethers (PBDEs) by means of gas chromatography with electron-capture detection (GC–ECD), with the identity of residues in some samples being confirmed by coupled gas chromatography–mass spectrometry. The concentrations of PBDEs were quantified in terms of commercial formulations (Great Lakes DE-71™, primarily pentabromodiphenylether [PeBDE]; Great Lakes DE-79™, primarily octabromodiphenylether; Great Lakes DE-83™, primarily decabromodiphenylether [deca-BDE]) and of three individual bromodiphenylether congeners, 2,2′,4,4′-tetrabromodiphenylether [TeBDE], and 2,2′,4,4′,5- and 2,2′,3,4,4′-PeBDEs. In total, 52 samples were analysed, comprising 29 sediment samples and 23 fish and shellfish tissues, the samples being collected from the Rivers Nith, Great Ouse, Humber, Calder, Ribble, Tweed (control site), Tees, and their estuaries and adjacent coastal waters. Detectable concentrations of Te- and PeBDEs were found in most samples. Deca-BDE was also evident in a number of sediment samples but, as in other studies, was not found in any of the biota samples analysed. Elevated concentrations were found in samples from the River Skerne/Tees system downstream of a plant manufacturing PBDEs, as well as in the sediments of the lower Tees estuary and in fish (dab, flounder, plaice) from Tees Bay. Detectable concentrations of TeBDE and one of the PeBDE congeners were also found in fish livers from offshore reference sites. The levels found in the livers of fish (dab, flounder) from Tees Bay were amongst the highest reported to date. High concentrations of deca-BDE ether were found in two sediment samples from the River Calder and one from the River Ribble, which is suggestive of a local point source.