Occurrence of dioxins (PCDDs, PCDFs) and polychlorinated biphenyls (PCBs) in wild, farmed and processed fish, and shellfish.

Forty-eight composite samples of the most commonly consumed fish and shellfish species were prepared from up to 60 individual subsamples of each species and analysed for chlorinated dioxins (PCDD/Fs) and polychlorinated biphenyls (PCBs). These included 24 species of fresh wild fish, seven of farmed fish, seven of fresh shellfish, and ten processed fish and shellfish products. The ISO 17025-accredited analytical methodology used is consistent with the requirements given in European Commission Directive 2002/69/EC. Concentrations ranged from 0.03 ng kg(-1) PCDD/F plus PCB World Health Organization-toxic equivalent quantity (WHO-TEQ) for a sample of surimi, to approximately 6 ng kg(-1) for wild pilchards/sardines. The corresponding range for the ΣICES-6 PCBs was 0.04 μ g kg(-1) to approximately 47 μ g kg(-1). None of the samples showed concentrations above the European Union maximum permitted limits. Averaged PCDD/F and PCB concentrations for the two groups of farmed and wild fish show that there is little difference between the two categories, although individual species may show variations depending on factors such as the sampling location.