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Vertical distribution of source apportioned PM2.5 using particulate-bound elements and polycyclic aromatic hydrocarbons in an urban area

Journal of Exposure Science & Environmental Epidemiology volume 30, pages 659–669 (2020)Cite this article

Abstract

Receptor models have been widely used for identifying and quantifying source-specific contributions from mixtures of air pollutants. Nonetheless, our knowledge is still limited on how various components of air pollution are vertically distributed and the sources of such pollutants. In this study, we collected 135 samples of PM2.5 (particles with aerodynamic diameter less than or equal to 2.5 µm) from building balconies at three altitudes in the metropolis of Taipei (Taiwan) and analyzed the samples for elements and polycyclic aromatic hydrocarbons that could be used to identify the sources of those pollutants. We used positive matrix factorization (PMF) to identify seven likely sources, including combustion, sulfur-rich aerosol, fresh traffic, industry/Cr-rich, oil combustion/vehicle, dust, and traffic. Although PM2.5 mass differed significantly between low-level and mid-level sites, the largest contributor to PM2.5 mass (sulfur-rich aerosol, 35.2%) showed nonsignificant variation in the vertical distribution. In contrast, oil combustion/vehicle, which exhibited significant difference between mid-level sites and the other two altitudes, might be a determinant in the vertical variation of PM2.5. We also observed negative trends with sampling height for combustion and traffic emissions.

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Acknowledgements

This study was supported in part by research grants from the Ministry of Science and Technology of Taiwan (MOST103‐2221‐E‐002‐008‐MY3, MOST105‐2811‐E‐002‐038, and MOST 106‐2811‐E‐002‐080), the National Taiwan University (105R4000), and the Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education of Taiwan (NTU-107L9003).

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  1. These authors contributed equally: Ho-Tang Liao, Jung-Chi Chang, Tzu-Ting Tsai

Authors and Affiliations

  1. Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei, 10055, Taiwan

    Ho-Tang Liao, Tzu-Ting Tsai & Chang-Fu Wu

  2. Research Center for Environmental Changes, Academia Sinica, Taipei, 11529, Taiwan

    Ho-Tang Liao & Charles C.-K. Chou

  3. Institute of Environmental Health, National Taiwan University, Taipei, 10055, Taiwan

    Jung-Chi Chang, Shih-Wei Tsai & Chang-Fu Wu

  4. Department of Public Health, National Taiwan University, Taipei, 10055, Taiwan

    Chang-Fu Wu

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Liao, HT., Chang, JC., Tsai, TT. et al. Vertical distribution of source apportioned PM2.5 using particulate-bound elements and polycyclic aromatic hydrocarbons in an urban area. J Expo Sci Environ Epidemiol 30, 659–669 (2020). https://doi.org/10.1038/s41370-019-0153-2

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