The study presents the analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/F) and dioxin-like polychlorinated biphenyls (dl-PCB) in fish and seabirds from the Baltic Sea area and the Arctic region (the Svalbard Archipelago). Long-time studies revealed no significant temporal trends in PCDD/F and dl-PCB concentrations in fish from the Baltic Sea. Trace amounts of PCDD/F were detected in the Arctic fish as an evidence of their anthropogenic sources from the temperate zone, however congener profile in the cod was entirely different than in the Baltic fish. On the contrary, both concentrations and profiles of dl-PCB were comparable in cod from the Baltic Sea and from the polar region. PCDD/F`s congener profile in African penguin`s tissues breed in captivity and fed only by herring exhibited a clear resemblance to the profiles measured in herring. This indicates a relevant impact of diet (fish) on PCDD/F`s level in seabirds. Diet impact on the further transfer of these xenobiotics in the trophic chain, evidenced in the presented study, appears to be of the particular relevance due to the human health.