Polychlorinated Biphenyls in Urban Lake Sediments and Migration Potential from Urban Stormwater in Bergen, Norway

Polychlorinated biphenyl (PCB) concentrations from an Cs137 age-dated core extracted from urban lake sediments in Bergen, Norway reflect the time period from the global introduction of PCB to the legal ban of their usage in Norway (1980). PCB concentrations in the sediment deposited after the ban of PCB usage strongly suggests that there are sources still active in the urban environment today. Earlier studies and results within this study imply that these sources could be standing building mass. The main pollution pathway from source to recipient is implied to be stormwater. This study presents a long-term measured amount of suspended particles in urban stormwater. An impervious, small urban catchment (5,800 m2) releases almost 800 kg of suspended solids per year in stormwater. This suggests that the whole drainage area of the lake potentially contributes 9.5 t of particles via stormwater into the lake each year, potentially carrying 0.4 g of PCBsum7.