Aerosol鈥揥ater Distribution of PCDD/Fs and PCBs in the Baltic Sea Region

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• 作者：Anna Sobek ; Hans Peter H. Arp ; Karin Wiberg ; Jenny Hedman ; Gerard Cornelissen
• 刊名：Environmental Science & Technology (ES&T)
• 出版年：2013
• 出版时间：January 15, 2013
• 年：2013
• 卷：47
• 期：2
• 页码：781-789
• 全文大小：368K
• 年卷期：v.47,no.2(January 15, 2013)
• ISSN：1520-5851

文摘

Atmospheric deposition is a major pathway of PCDD/Fs to the Baltic Sea. We studied the aerosol鈥搘ater 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-渭m polyoxymethylene equilibrium passive samplers). Concentrations of PCDD/F and sum PCB-7 in aerosols were 65鈥?300 pg/g dw TEQ and 22鈥?00 ng/g dw, respectively. Organic carbon (OC)-normalized aerosol鈥搘ater distribution ratios (K_aer-water,OC) were consistently lower (factor 2鈥?0) than previously determined sediment organic carbon鈥搘ater distribution ratios (K_sed,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/Fs and PCBs sorbed to sediment. Further, we investigated whether aerosol鈥搘ater distribution may be predicted from the air鈥揳erosol partitioning constant multiplied by the Henry鈥檚 Law constant. This proposed model for aerosol鈥搘ater distribution underestimated measured values for PCBs by factors of 1鈥?7 and for PCDD/Fs by more than a factor 10. These findings can be used to improve future fate modeling of PCBs and PCDD/Fs in marine environments and specifically the Baltic Sea.