Atmospheric concentrations and gas-particle partitioning of PCDD/Fs and dioxin-like PCBs around Hochiminh city

• Published in: Chemosphere (Oxford) 2018-07, Vol.202, p.246-254
• Main Authors: Trinh, Minh Man, Tsai, Ching Lan, Hien, To Thi, Thuan, Ngo Thi, Chi, Kai Hsien, Lien, Chien Guo, Chang, Moo Been
• Format: Article
• Language: English
• Subjects: Ambient air; Dioxins; dl-PCBs; Gas/particle partitioning; Vietnam
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2018.03.087

Atmospheric PCDD/Fs and dl-PCBs samples were collected in Hochiminh city, Vietnam to address the effect of meteorological parameters, especially rainfall, on the occurrence and gas/particle partitioning of these persistent organic pollutants. The results indicate that PCDD/Fs and dl-PCBs concentrations in industrial site are higher than those measured in commercial and rural sites during both rainy and dry seasons. In terms of mass concentration, ambient PCDD/F levels measured in dry season are significantly higher than those measured in rainy season while dl-PCB levels do not vary significantly between rainy and dry seasons. The difference could be attributed to different gas/particle partitioning characteristics between PCDD/Fs and dl-PCBs. PCDD/Fs are found to be mainly distributed in particle phase while dl- PCBs are predominantly distributed in gas phase in both rainy and dry seasons. Additionally, Junge-Pankow and Harner-Bidleman models are applied to better understand the gas/particle partitioning of these pollutants in atmosphere. As a results, both PCDD/Fs and dl-PCBs are under non-equilibrium gas/particle partitioning condition, and PCDD/Fs tend to reach equilibrium easier in rainy season while there are no clear trend for dl-PCBs. Harner-Bidleman model performs better in evaluating the gas/particle partitioning of PCDD/Fs while Junge-Pankow model results in better prediction for dl-PCBs. [Display omitted] •Influence of rainfall on PCDD/Fs and dl-PCBs in the atmosphere is studied.•PCDD/Fs concentrations in the dry season are higher than that in the rainy season.•Dl-PCBs concentrations do not vary much between dry and rainy seasons.•The accuracy of two gas/particle partitioning models is compared.