Characteristics and Source Apportionment of Atmospheric PM2.5 at a Coastal City in Southern Taiwan

Abstract

Fine particulate matters (PM 2.5 ) has been identified as one of the major air pollutants in urban areas, which are responsible for the adverse effects on public health and the deterioration of visibility. New PM 2.5 air quality standards were promulgated in Taiwan on 14 th May 2012, as well as the standard sampling and analytical method for atmospheric PM 2.5 (NIEA A205.11C) on 24 th April 2012. In this study, the atmospheric levels and characteristics of PM 2.5 in Tainan during 2013 were evaluated by measuring the mass concentration of PM 2.5 and analyzing the water-soluble ionic, carbon, and metal components. Additionally, a Chemical Mass Balance (CMB) receptor model was used to identify possible sources of PM 2.5 and their contributions. Based on results of this study, the current PM 2.5 levels in Tainan in spring and winter (41-49 µg m -3 ) were substantially higher than the yearly average PM 2.5 air quality standards (15 µg m -3 ). According to chemical composition analysis, secondary aerosols (NH 4 + , NO 3 -, and SO 4 2-) contributed approximately 50% and 60% of PM 2.5 mass in spring and winter respectively; but were responsible about 40% by mass in summer at both Tainan and Xinying stations. From the results of CMB model, the main contribution sources to the PM 2.5 in Tainan are traffic emissions (31.5%), ammonium sulfate (25.5%), ammonium nitrate (12.5%), and crustal elements (11%). Consequently, to improve PM 2.5 of Tainan City, the priority control pollutants (or sources) are primary PM 2.5 (open burning, construction sites and road dust by vehicles), NO x (diesel vehicle emissions), and SO x (fuels).

Characteristics of Atmospheric PM2.5 in a Densely Populated City with Multi-Emission Sources

“…The secondary sulfate (18.2%), secondary nitrate (17.1%), traffic source (15.6%), petrochemical industry (9.08%), resuspending soil particle (8.10%), agricultural open burning (7.79%), sea salt (7.43%), cement industry (5.19%), and metallurgical industry (3.80%) were the main contributing sources in autumn while for winter traffic source (21.6%), secondary nitrate (18.1%), secondary sulfate (13.0%), agricultural open burning (9.89%), petrochemical industry (9.23%), re-suspending soil particle (8.32%), sea salt (5.36%), cement industry (3.20%), and metallurgical industry (3.20%). Similar to our previous study identified ammonium sulfate, ammonium nitrate and traffic sources as the main contributors of PM 2.5 in Tainan City of Taiwan, which indicates that control of PM 2.5 in the ambient air of Chiayi and Tainan Counties should focus on NO x , SO x and traffic emissions (Lu et al, 2016). ), when the lowest one, were registered in the summer (9-22 µg m -3 ) around Chiayi City.…”

“…The reason is NO 3 -and NH 4 + will volatilize from surface of PM. Similarly, other studies have shown that NO 3 -, SO 4 2-and NH 4 + as the dominant water soluble ions (Shen et al, 2009;Deshmukh et al, 2011;Wang et al, 2015a;Lu et al, 2016). The higher contribution of NO 3 -and SO 4 2-signifies the occurrence of atmospheric oxidation process for NO 2 and SO 2 (Lin, 2002).…”

Characteristics and Source Analysis of Trace Elements in PM2.5 in the Urban Atmosphere of Wuhan in Spring

“…Typical sources of air pollution in big cities can be vehicle emissions, dust resuspension, secondary aerosol formation, industrial emissions, biomass or coal burning, power plant emissions etc. (Lu et al, 2016). The characteristics of PM sources have been widely investigated in previous studies all around world, including China, as reviewed by (Karagulian et al, 2015), and several methods of receptor modeling have been used for identification and apportionment of PM (Viana et al, 2008).…”

Atmospheric Deposition of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans in Two Cities of Southern China

“…Previous investigations have shown good correlations between PM 10 and total-PCDD/Fs mass concentrations (Wang et al, 2010;. Higher PM 2.5 and PCDD/Fs levels are contributed by anthropogenic rather than natural sources, with seasonal variations in these (Yu et al, 2013;Wang et al, 2015;Lu et al, 2016). Ambient particulate matters can be removed from atmosphere by both dry and wet deposition (Cheruiyot et al, 2015(Cheruiyot et al, , 2016.…”