In most areas, concentrations of lead in fish and shellfish are above background levels, and mercury above the environmental threshold. Cadmium was above background levels in northern and eastern areas. Despite bans, concentrations in biota are mostly increasing, particularly in the Greater North Sea (Region II). Concentrations in sediments are often above the environmental thresholds but decreasing in most subregions.

Although mean concentrations of polycyclic aromatic hydrocarbons (PAHs) in shellfish and sediment, and PAH bile metabolites in fish, in most assessed areas are above background concentrations, they are below levels likely to harm marine species. Concentrations are decreasing or stable in all, but one (Irish and Scottish West Coast sediment) area assessed. ^{Image © Marine Scotland Science}

Biota sites have good geographical coverage, sediment sites are more limited. PBDEs in sediment and biota have been stable (54% of assessed areas) or declining (46%) for the past 20 years. Concentrations are below thresholds (FEQGs) for all assessment areas and congeners, except BDE209 in Irish Sea sediment, and should not cause adverse effects to marine wildlife.

Polychlorinated biphenyls (PCBs) were banned in many countries in the mid-1980s. Although local problems remain, PCB concentrations in sediment and biota have decreased in most OSPAR assessment areas. With the exception of the most toxic congener (CB118), concentrations are below the level at which they could present an unacceptable risk to the environment.