Volume 12, No. 5, October 2012, Pages 1016-1029 PDF(1.57 MB)
Atmospheric Dry Deposition of Polychlorinated Dibenzo-p-Dioxins/Dibenzofurans (PCDD/Fs) and Polychlorinated Biphenyls (PCBs) in Southern Taiwan
Hsiao-Hsuan Mi1, Zong-Sian Wu2,3, Long-Full Lin4, Yi-Chieh Lai5,6, Yen-Yi Lee6, Lin-Chi Wang6,7, Guo-Ping Chang-Chien6,8
1 Department of Environmental Engineering and Science, Chia-Nan University of Pharmacy and Science, 60 Erren Road, Tainan 71710, Taiwan
2 Department of Environmental Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
3 Sustainable Environment Research Center, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
4 Department of Environmental Engineering, Kun Shan University, 949 Da Wan Road, Tainan 71003, Taiwan
5 Center for General Education, Cheng Shiu University, 840 Chengcing Road, Kaohsiung City 83347, Taiwan
6 Super Micro Mass Research and Technology Center, Cheng Shiu University, 840 Chengcing Road, Kaohsiung City 83347, Taiwan
7 Department of Civil Engineering and Engineering Informatics, Cheng Shiu University, 840 Chengcing Road, Kaohsiung City 83347, Taiwan
8 Department of Chemical and Materials Engineering, Cheng Shiu University, 840 Chengcing Road, Kaohsiung City 83347, Taiwan
Dry deposition is one of the major routes by which air pollutants enter the ecosystem, and thus this study investigated the dry deposition characteristics of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and biphenyls (PCBs) in the ambient air of industrial, urban, and rural areas in southern Taiwan from November 2010 to May 2011. Average dry deposition fluxes of total PCDD/Fs and PCBs in the ambient air of four sites were 157–544 pg/m2-day (8.30–27.5 pg I-TEQ/m2-day) and 289–1010 pg/m2-day (0.540–1.94 pg WHO-TEQ/m2-day), respectively. The results showed that particle phase depositions dominated the dry deposition processes for the removal of PCDD/Fs and PCBs from the atmosphere, and the atmospheric deposition flux in the cold season tended to be higher than that during the warm season. The dry deposition velocity of individual PCDD/Fs (0.031–0.546 cm/s) increased as the number of chlorinated substitutes increased, which were similar to those measured or predicted in other Asian countries. Similar patterns of dry deposition velocities were observed for individual PCBs (0.069–3.38 cm/s), due to the fact that low chlorinated PCBs are predominant in gas phase and have lower deposition velocities.
Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs); Polychlorinated biphenyls (PCBs); Gas-Particle partitioning; Dry deposition flux; Dry deposition velocity.