Cite this article: Tseng, Y.J., Mi, H.H., Hsieh, L.T., Liao, W.T. and Chang-Chien, G.P. (2014). 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.
Aerosol Air Qual. Res.
14: 1966-1985. https://doi.org/10.4209/aaqr.2014.07.0150
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).