Contaminants in sediment and biota
Contaminants (PAHs, PCBs, PBDEs and heavy metals) are measured in sediment and biota (mussels and fish). Contaminants can be incorporated onto particulate matter, and be deposited on the sea bed. Many contaminants can also accumulate in fish and shellfish, because they are taken in either directly from the marine environment or indirectly through food consumption. The two case studies Case study: PBDEs in grey seals and Case study: PCBs in grey seals highlight how monitoring the levels of persistent organic pollutants (POPs) in grey seals can give an indication of levels of these pollutants in the wider North Sea.