Ambient air particulates, metallic elements, dry deposition and concentrations at Taichung Airport, Taiwan

The characterization of water-soluble species of dry deposition flux, total suspended particulates (TSPs), fine particles (particle matter with aerodynamic diameters < 2.5 μm (PM2.5)), coarse particles (particle matter with aerodynamic diameter 2.5–10 μm (PM2.5–10)), and dry deposition velocity were studied at Taichung Airport sampling sites in central Taiwan between Sept. and Dec. 2004. The average TSP concentrations at Taichung Airport were about 0.8 times that of the harbor sampling site in central Taiwan. Additionally, the average dry deposition velocities (for TSPs) for metallic elements Fe, Mn, Cu, Zn, Pb, Cr and Mg were 1.54 ± 0.44, 0.86 ± 0.31, 0.77 ± 0.32, 0.62 ± 0.24, 1.21 ± 0.42, 0.82 ± 0.14 and 1.64 ± 0.26 (cm s− 1), respectively, at the airport sampling site. Furthermore, metallic element concentrations in fine and coarse particulate matter in air samples were also analyzed. The average ratios of fine to coarse for metallic elements Fe, Mn, Cu, Zn, Pb, Cr and Mg were 5.04 ± 1.87, 1.80 ± 0.60, 1.80 ± 0.76, 2.89 ± 0.72, 1.75 ± 0.36, 1.58 ± 0.39 and 2.33 ± 1.87, respectively. The results indicated that the metallic elements in the fine particulate matter accounted for the majority of particulates at the Taichung Airport sampling site.