Airborne Polycyclic Aromatic Hydrocarbons (PAH) in Bangkok Urban Air: Part II. Level and Distribution |
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| Authors: | H. Garivait C. Polprasert K. Yoshizumi L. Baetz Reutergardh |
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| Affiliation: | 1. Environmental Research and Training Center , Technopolis, Klong Luang, Pathumthani , 12120 , Thailand;2. Environmental Engineering Division , Asian Institute of Technology , P.O. Box 4, Klong Luang, Pathumthani , 12120 , Thailand;3. Kyoritsu Women's University , 2-2-1 Hitotsubashi, Chiyoda-ku, Tokyo , 101 , Japan;4. River Basin Environment Research Center , Gifu University , 1-1, Yanagido , Japan |
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| Abstract: | The gas-particle partitioning and particle size distributions of airborne PAH in Bangkok urban air were investigated using an 8 stage size fractionating cascade impactor (Andersen “low volume” sampler) and a downstream XAD-2 adsorbent tube for sample collection. Nine PAH classified as carcinogenic and co-carcinogenic compounds-Pyrene (PYR), Benz(a)Anthracene (BaA), Benzo(e)Pyrene (BeP), Dibenz(a,c)Anthracene (DBacA), Benzo(k)Fluoranthene (BkF), Benzo(a)Pyrene (BaP), Dibenz(a,h)Anthracene (DBahA), Benzo(ghi)Perylene (BghiP) and Trimethylcholanthrene (3MC) - were quantified. The lower molecular weight (MW) PAH such as PYR, BeP and BaA were present mainly in the gaseous phase (80%, 40% and 24%, respectively) while higher MW compounds were present almost totally in the particulate fraction. The results show that 30%–60% of each PAH by mass were found on particles smaller than 0.43 μm and more than 70% on particles with diameter less than 2.1 μm. In addition, the relationship between the particle/gas partition coefficient (K p ) and the sub-cooled liquid vapor pressure (p°L) was also determined to describe the gas-particle partitioning of those PAH compounds in a tropical atmosphere. |
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| Keywords: | Airborne PAH Level and distribution Gas-particle partitioning Particle size dependency Bangkok urban air |
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