Background. Dietary guidelines recommend that fish should be consumed at least twice a week due to valuable nutrients they contain, like long-chain, polyunsaturated fatty acids, macro- and microelements, fat-soluble vitamins (mainly D3), amino acids and easily digestible protein. Apart from the benefits, fish consumption becomes a source of toxic compounds including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs). The aim of our research was to investigate the levels of PCDD, PCDF and PCB in marine fish imported to Poland and assess the risk for consumers, taking into account the tolerable weekly intake (TWI) of 2 pg WHOTEQ/kg body weight (b.w.). Six fish species were investigated: turbot, mackerel, Atlantic salmon, tuna, pollock and hake. The method employed for the research was isotope dilution technique with highresolution gas chromatography coupled with high resolution mass spectrometry (HRGC-HRMS).
Results and conclusions. The highest concentrations for the sum of PCDD/F/dl-PCB were determined in turbot muscles 1.25 pg WHO-TEQ/g of fresh weight (f.w.) and the lowest in pollock, hake and tuna muscles 0.02, 0.03, 0.04 pg WHO-TEQ/g f.w. respectively. Although the tested fish contained low PCDD/F/PCB concentrations compared to the permissible limits, the consumption of the recommended two portions of the most contaminated species resulted in TWI being exceeded even six times for children and two times for adults. Imported turbot, salmon and mackerel are significant sources of dioxins and PCBs for fish consumers.