Chemical Composition and Source Apportionment of Wintertime Airborne PM<sub>2.5</sub> in Changchun, Northeastern China
This study presents field observations and laboratory analyses of wintertime airborne particulate matter (PM<sub>2.5</sub>) and its chemical components in the Changchun metropolitan area, the geographical center of northeastern China. Twenty-four hour PM<sub>2.5</sub> filter...
Main Authors: | , , , , , , , , |
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Format: | Article |
Language: | English |
Published: |
MDPI AG
2021-04-01
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Series: | International Journal of Environmental Research and Public Health |
Subjects: | |
Online Access: | https://www.mdpi.com/1660-4601/18/8/4354 |
Summary: | This study presents field observations and laboratory analyses of wintertime airborne particulate matter (PM<sub>2.5</sub>) and its chemical components in the Changchun metropolitan area, the geographical center of northeastern China. Twenty-four hour PM<sub>2.5</sub> filter samples were collected from 23 December 2011 to 31 January 2012 at four sites in the types of traffic, residential, campus, and a near-city rural village, respectively. Daily PM<sub>2.5</sub> concentrations ranged from 49 to 466 µg m<sup>−3</sup>, with an arithmetic average of 143 µg m<sup>−3</sup>. Laboratory analyses showed that among all measured chemical species, mineral dust contributed the largest proportion (20.7%) to the total PM<sub>2.5</sub> mass, followed by secondary inorganic aerosols (SIA, including SO<sub>4</sub><sup>2−</sup>, NO<sub>3</sub><sup>−</sup> and NH<sub>4</sub><sup>+</sup>), which constituted 18.8% of PM<sub>2.5</sub> mass. Another notable feature of PM<sub>2.5</sub> chemical composition was high halogen (Cl<sup>−</sup> and F<sup>−</sup>) loadings at all sites, which was likely due to emissions from coal combustion, plastic manufacturing, and glass melting. Among the four sampling sites, the suburban site exhibited the highest PM<sub>2.5</sub> levels and extremely high Cl<sup>−</sup> and F<sup>−</sup> loadings due to residential wood burning and nearby industrial facilities lacking effective emission controls. Our results report one of the earliest observations of PM<sub>2.5</sub> composition in this region, providing a baseline of aerosol profiles of aerosol before PM<sub>2.5</sub> was routinely measured by environmental protection agencies in China, which could be useful for assessing long-term trends of air quality and effectiveness of mitigation measures. |
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ISSN: | 1661-7827 1660-4601 |