This study explores the effects of an Asian dust storm (ADS) and Southeast Asian biomass burning on the composition of atmospheric aerosols in the coastal area of southern Taiwan in spring 2010. Coarse and fine particles were collected using two manual dichotomous samplers (Dichots) that were equipped with Teflon and Quartz filters. The results reveal that the concentrations of PM 10 and PM 2.5 in the ADS period were about twice those before and after this. More than half of water-soluble ions in coarse particles (PM 2.5-10 ) were Cl -and Na + (sea salt), while 70% of water-soluble ions of fine particles were SO 4 2-and NH 4 + (secondary aerosols). The OC/EC ratios of PM 2.5 and PM 2.5-10 were all above 2.0. Over 98% of the metals in coarse and fine particles were crustal elements (98.1-99.1%), and over 60% of the metals in PM 10 were in coarse particles (PM 2.5-10 ). The water-soluble ion, EC, OC, and metal contents in PM 2.5 all exceeded those in PM 2.5-10 . The ADS was associated with higher concentrations of water-soluble ions in PM 2.5 and PM 2.5-10 than was the non-ADS period, except for K + in PM 2.5-10 . ADS most increased the Ca 2+ content and concentration, causing a rise in the average concentrations of Ca 2+ in coarse and fine particles by factors of 3.0 and 3.2, respectively. In the ADS period, although the OC and EC concentrations of coarse and fine particles increased, the OC and EC contents in these particles decreased. The ADS period was associated with higher metal contents in coarse and fine particles than the non-ADS period, and the increase in PM 2.5-10 (more than 2%) exceeded that in PM 2.5 . In PM 2.5-10 and PM 2.5 , the Ca and Ni contents increased the most, respectively. In addition, the concentrations of the water-soluble ions, EC, OC, and metals in PM 2.5-10 and PM 2.5 increased, but their contents decreased, while the contents of the other constituents (= total -(water-soluble ions + EC + OC + metals)) in PM 2.5-10 and PM 2.5 increased. It is also found that Southeast Asian biomass burning is related to the deterioration of the air quality of southern Taiwan.

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This study investigates water-soluble ions in the sized particles (particularly Aitken nuclei mode (dp ≤ 0.1 µm, PM 0.1 )/ accumulation mode (0.1 < dp ≤ 1.0 µm, PM 0.1-1.0 )) collected using a MOUDI sampler in the YanShuei area of southern Taiwan during a beehive fireworks display. The results indicate that the PM 2.5 and PM 10 concentrations (437 µg/m 3 and 572 µg/m 3 , respectively) at the leeward sampling site are 12.5 and 4.6 times higher than the corresponding national standards of daily mean values (35 and 125 µg/m 3 , respectively) during the beehive fireworks display. Closely examining PM accumulation fractions reveals that the accumulation mode particles dominate in the sized collected particles during the beehive fireworks display. Additionally, the K + concentrations in PM 1.0 , PM 2.5 , and PM 2.5-10 are 317, 349, and 249 times higher than those of its background value, while those of Cl -are 91, 64, and 6.9 times greater than those of its background value. For ultrafine particles, the D/B (During the beehive fireworks display/Background) values of particlebound Cl -, K + , and Mg 2+ increase significantly during the beehive fireworks display at the leeward sampling site. Moreover, the maxima D/B value of K + is 196 in the 0.1-0.18 m size range, revealing that the beehive firework aerosols are rich in Cl -, K + , and Mg 2+ ions.

This study investigates metals in the PM 1.0 and PM 2.5 collected using a micro-orifice uniform deposition impactor (MOUDI) sampler in the YanShuei area of southern Taiwan during a beehive firework display. The results of sample analyses indicate that during the beehive firework display, the ratios of metal concentrations in PM 2.5 (D) to the background level (B) at leeward sampling site were 1,828 for Ba, 702 for K, 534 for Sr, 473 for Cu, 104 for Mg, 121 for Al, and 98 for Pb. The corresponding data for PM 1.0 were 3036, 838, 550, 676, 594, 190, and 126, respectively. According to the results of metal composition ratio, Principal Component Analysis (PCA), and upper continental crust (UCC) analyses, the concentrations of particle-bound Al, Ba, Cu, K, Mg, Pb, and Sr increased during the beehive firework displays, suggesting that firework-display aerosols contained abundant metal elements of Al, Ba, Cu, K, Mg, Pb, and Sr. Before (background), trial, during, and after the beehive firework display, the Ba, K, Cu, Mg, Pb, and Sr (commonly regarded as firework display indicator elements) accounted for 0.520, 2.45, 26.4 and 0.849% mass of PM 1 , respectively, while for PM 2.5 the corresponding data were 0.777, 2.32, 23.8, and 0.776%, respectively.