Modelling of detailed transformations of PCB 153 and PCB 28 in coastal regions

Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) that have a long residence time in the marine environment. Due to processes of biomagnification in food chains, their presence in aquatic matrices is especially harmful for living organisms (incl. humans). The process of photolysis in the upper layers of the water column leads to a decreasing concentrations of higher chlorinated congeners (HCC) and increases the concentration of lower chlorinated congeners via the process of HCC declorination. This impacts the environmental fate of pollutants (e.g. sedimentation, accumulation, air-sea exchange), especially in coastal areas. Additionally, depending on the pollutant, degradation products can be even more harmful than the originally emitted species.

To estimate the environmental fate of the chosen contaminants in the marine ecosystems, a Framework for Aquatic Biogeochemical Models (FABM) has been implemented into a high-resolution numerical model. The first results of modeling PCBs concentrations will be presented for 1d simulations including factors such as light penetration, mixing, remineralisation and resuspension and the biological pump. This study aims to compare results for different regions and regimes with different conditions.