Volume 14, No. 7, December 2014, Pages 1966-1985 PDF(987 KB)
Atmospheric Deposition Modeling of Polychlorinated Dibenzo-p-dioxins, Dibenzofurans and Polychlorinated Biphenyls in the Ambient Air of Southern Taiwan. Part II. Wet Depositions and Total Deposition Fluxes
Yu-Jung Tseng1, Hsiao-Hsuan Mi2, Lien-Te Hsieh3, Wei-Tung Liao4, Guo-Ping Chang-Chien5
1 Department of Environmental Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
2 Department of Environmental Engineering & Science, Chia Nan University of Pharmacy and Science, Tainan 71743, Taiwan
3 Department of Environmental Engineering and Science, National Pingtung University of Science and Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan
4 Department of Chemical and Materials Engineering, Southern Taiwan University of Science and Technology, No. 1, Nan-Tai Street, Yungkang Dist., Tainan 71005, Taiwan
5 Super Micro Mass Research and Technology Center, Cheng Shiu University, 840, Chengching Road, Kaohsiung 83347, Taiwan
- The wet deposition flux increased with rainfall intensity.
- The simulated wet deposition results are dominated by particulate phase.
- The average total PCDD/F and PCB-TEQ2005 (dry + wet) flux was high in winter.
The wet deposition flux increased with stronger rainfall intensity. From the congener profiles of PCDD/F and PCB WHO-TEQ2005 total deposition fluxes, 2,3,4,7,8-PeCDF, 2,3,4,6,7,8-HxCDF, 1,2,3,4,7,8-HxCDF and 1,2,3,7,8-PeCDD dominate the deposition fluxes. PCB-126 and PCB169 are the two most significant congeners that dominate the PCB WHO-TEQ2005. The simulated results show that the monthly PCDD/F and PCB wet deposition fluxes during 2012 were in the range of 9.26–265 pg WHO-TEQ2005/m2-month and 0.205–9.38 pg WHO-TEQ/m2-month, respectively. The monthly PCDD/F and PCB wet deposition fluxes during 2013 were 0.152–211 pg WHO-TEQ2005/m2-month and 0.00823–6.84 pg WHO-TEQ/m2-month, respectively. Wet deposition mainly occurs in the high rainfall intensity seasons, such as summer. The simulated results indicate that wet deposition is dominated by the particulate phase. Regarding the annual PCDD/F and PCB total (dry + wet) WHO-TEQ2005 deposition fluxes, dry deposition fluxes account for 68.0–73.9%. Among these, PCDD/Fs dominate the total deposition (95.9–96.1%) and PCBs contribute only 3.9–4.1%. The average total PCDD/F and PCB-TEQ2005 deposition (dry + wet) flux in winter (317–429 pg WHO-TEQ/m2-month) was 1.46–2.63 times higher than that in summer (163–216 pg WHO-TEQ/m2-month).
PCDD/Fs; PCBs; Wet deposition; Scavenging.