Determination of Hydroxylated Polybrominated Diphenyl Ethers in Blood from Baltic Grey Seals

Abstract

Naturally produced hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have been extensively studied in the lower end of the Baltic Sea food web. Certain OH-PBDE congeners have displayed increasing concentrations over the last 30 years in herring (Clupea harengus) from the Baltic proper. However, studies on the top carnivores in the Baltic Sea are scarce. Quantitative data on OH-PBDEs exist for ringed seal (Pusa hispida) from the Gulf of Bothnia, but only a limited amount of data have been produced with regard to Baltic grey seal (Halichoerus grypus), and seals from the Baltic proper. A method was developed and evaluated for quantification of OH-PBDEs in coagulated whole blood. The method was applied on blood obtained from dead grey seals originating from different parts of the Baltic Sea. The levels of OH-PBDEs were observed to be low in the analyzed seals in comparison with reported levels in white-tailed sea eagle nestlings (Halizeetus albicilla), and some Baltic fish species. The levels of the dominant congener, 6-OH-BDE47, were statistically significantly higher in seals from the Baltic proper than in seals from the Gulf of Bothnia. Hydroxylated polychlorinated biphenyls (OH-PCBs) were observed to be of much higher concentration than the OH-PBDEs in the analyzed seals. The average concentration of the dominant OH-PCB congener, 4-OH-CB107, was one order of magnitude greater than that of 6-OH-BDE47.