Aerosol-water distribution of PCDD/Fs and PCBs in the Baltic Sea region

摘要: Atmospheric deposition is a major pathway of PCDD/Fs to the Baltic Sea. We studied the aerosol–water distribution for aerosols collected close to the Baltic Sea in order to investigate the availability of pollutants sorbed to aerosols deposited on water. Aerosols were analyzed for both total concentration (Soxhlet extraction) and the freely dissolved water concentration (extraction with 17-μm polyoxymethylene equilibrium passive samplers). Concentrations of PCDD/F and sum PCB-7 in aerosols were 65–1300 pg/g dw TEQ and 22–100 ng/g dw, respectively. Organic carbon (OC)-normalized aerosol–water distribution ratios (Kaer-water,OC) were consistently lower (factor 2–60) than previously determined sediment organic carbon–water distribution ratios (Ksed,OC). Hence PCDD/Fs and PCBs entering the Baltic Sea through aerosol deposition seem to be more available for desorption to the water phase than PCDD …