Determination of levels of polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls and pesticides in harp seals from the Greenland Sea

The levels of polychlorinated dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF), biphenyls (PCB) and compounds of the DDT group were determined in individual seal blubber and brain samples from ten male and one female harp seals caught in the Greenland Sea. No data from this region and from harp seals have been reported before. The age of the animals varied between 1 and 18 years. PCDD/PCDF concentrations in the blubber (4–10 pg/g TEQ wet weight (w.w.), Nordic model) were somewhat lower than in ringed seals from the Arctic. Non-ortho substituted PCB (CB 77,126 and 169) showed TEQ levels in the blubber which were about 4–10-times higher. CB 77 dominated in most samples, but in a few cases CB 169 was the most abundant congener. p,p′-DDE (average 760 ng/g w.w.) and di-ortho substituted PCB concentrations (2560 ng/g w.w. expressed as ΣPCB) in the blubber were comparable to those found in ringed seals from the European and Canadian Arctic. Levels of PCDD/PCDF in brain correspond to the detection limit (about. 0.1 – 0.6 pg/g w.w.) for most congeners. With one exception, PCB amounts in brain (w.w.) were one to two orders of magnitude lower. A highly significant correlation was found between age, p,p-DDE and di-ortho PCB as well as between single PCDD and coplanar PCB congeners. No relationship was observed between levels of PCDD/PCDF, age and di-ortho-PCB.