Characteristics of PM2.5 in an Industrial City of Northern China: Mass Concentrations, Chemical Composition, Source Apportionment, and Health Risk Assessment

Abstract

Urban and suburban PM2.5 samples were collected simultaneously during selected periods representing each season in 2019 in Zibo, China. Samples were analysed for water-soluble inorganic ions, carbon components, and elements. A chemical mass balance model and health risk assessment model were used to investigate the source contributions to PM2.5 and the human health risks posed by various pollution sources via the inhalation pathway. Almost 50% of the PM2.5 samples exceeded the secondary standard of China’s air quality concentration limit (75 µg/m3, 24 h). Water-soluble inorganic ions were the main component of PM2.5 in Zibo, accounting for 50 ± 8% and 56 ± 11% of PM2.5 at the urban and suburban sites, respectively. OC and OC/EC decreased significantly in the past few years due to enhanced energy restructuring. Pearson correlation analysis showed that traffic emissions were the main source of heavy metals. The Cr(VI) concentrations were 1.53 and 1.92 ng/m3 for urban and suburban sites, respectively, exceeding the national ambient air quality standards limit of 0.025 ng/m3. Secondary inorganic aerosols, traffic emissions, and secondary organic aerosols were the dominant contributors to PM2.5 in Zibo, with the total contributions from these three sources accounting for approximately 80% of PM2.5 and the remaining 20% attributed to traffic emissions. The non-carcinogenic risks from crustal dust for children were 2.23 and 1.15 in urban and suburban areas, respectively, exceeding the safe limit of 1.0 in both locations, as was the case for adults in urban areas. Meanwhile, the carcinogenic risks were all below the safe limit, with the non-carcinogenic and carcinogenic risks from traffic emissions being just below the limits. Strict control of precursor emissions, such as SO2, NOx, and VOCs, is a good way to reduce PM2.5 pollution resulting from secondary aerosols. Traffic control, limiting or preventing outdoor activities, and wearing masks during haze episodes may be also helpful in reducing PM2.5 pollution and its non-carcinogenic and carcinogenic health impacts in Zibo.

PM2.5 at a semi‐rural site near Beijing, China

“…Zhang et al 33 also measured PM 2.5 in Zibo, in 2006–2007, and reached a mean annual PM 2.5 concentration of 165 μg/m 3 , Figure 1. These high concentrations were obtained 10 years prior to the current study and the study by Bai et al 32 and are in line with the increased air quality in China. The findings from the current study are in line with the other studies showing a decreasing air pollution situation in many Chinese regions.…”

“…Ming Tombs [30] Chengdu, winter [31] Chengdu, spring [31] Zibo, 2019 [32] Zibo, 2006 [33] Zhang et al 33 measured the same elements as in Table 3 and K, Ca, Ti, V, Mn, Ni, Cu, and As were in the same order of magnitude as in the current study, despite the different site characteristics. The more industry-related elements S, Cl, Fe, Zn, and Pb had higher concentrations in Zibo compared to Changping.…”

“…Their measurement site was in the center of the bigger city of Chengdu. In Northeast China, Bai et al 32 measured PM 2.5 in 2019 at a sub‐urban and an urban part of the industrial city Zibo, Figure 1. They reported a springtime mean PM 2.5 concentration of approximately 60 μg/m 3 at both sites.…”

Influence of Urbanization on the Spatial Distribution of Associations Between Air Pollution and Mortality in Beijing, China

“…We hope to use finer‐resolution data to measure the spatial variations in the health risks of air pollution in future studies. Finally, differences in chemical constituents of the air pollutants between urban and suburban areas also contribute to discrepancies in the associated health risks (Bai et al., 2022; B. Li et al., 2021). However, we could not analyze the underlying impacts of the chemical composition owing to the lack of data.…”

Using Stable Sulfur Isotope to Trace Sulfur Oxidation Pathways during the Winter of 2017–2019 in Tianjin, North China

“…In recent years, many urban areas in China have been severely affected by haze [ 1 , 2 , 3 ]. The primary emissions, secondary formation and transformation, and stable weather conditions have been considered as the main reasons for such widespread and continuous high loading of air pollutants, including haze, over China [ 4 , 5 , 6 ].…”