Pollution characteristics, source apportionment and health risks assessment of fine particulate matter during a typical winter and summer time period in urban Taiyuan, China

Abstract

The concentrations of ambient fine particulate matter (PM_2.5) and its compositions in urban Taiyuan, China during a typical winter and summer time period in 2017 were measured to investigate the pollution characteristics, source apportionment and health risks assessment of PM_2.5 pollution. The results demonstrated that the mean daily mass concentration of PM_2.5 in winter (102.6 ± 6.2 μg/m³) was higher than that in summer (65.0 ± 17.2 μg/m³) during sampling. The relatively high concentrations of heavy metals (Zn, Pb, Cu, As, Ni, Cr and Cd), anion (SO₄²⁻, NO₃⁻, Cl⁻ and F⁻) and high-molecular-weight PAHs in PM_2.5 were observed. The enrichment factors (EFs) values, special diagnostic ratios like ratios of NO₃⁻/SO₄²⁻ and individual PAHs concentration ratio showed that coal combustion and vehicle emissions were the major sources of PM_2.5 pollution. Health risk assessment illustrated that mean hazard indices for non-cancer and cancer risk of all analyzed metals were within the safe range. However, inhalation exposure to PM_2.5-bound PAHs had carcinogenic risk, while not indicating non-carcinogenic risk. Taken together, although PM_2.5 pollution was alleviated to some extent, PM_2.5 pollution in 2017 was still serious and PM_2.5 was mainly originated from coal burning, especially, in which PM_2.5-bound PAHs in Taiyuan may pose a potential health risk.

Keywords:

• fine particulate matter
• pollution characteristics
• source apportionment
• health risks assessment
• Taiyuan

Additional information

Funding

This research was supported by the National Natural Science Foundation of China (Nos. 91843301 and 91543202), the Nature Science Foundation of Shanxi Province in China (201801D121260) and the Hundred Talents Program of Shanxi Province in China.