Pollution characteristics, source apportionment, and health risk assessment of PM2.5-bound polycyclic aromatic hydrocarbons in Guangzhou City from 2016 to 2024
- VernacularTitle:2016—2024年广州市大气PM2.5中多环芳烃污染特征、来源及健康风险评估
- Author:
Yan WU
1
;
Zhi LI
2
;
Jiayun LYU
1
;
Jie SHI
1
;
Yongquan PENG
1
;
Wenru FENG
1
Author Information
- Publication Type:Investigation
- Keywords: fine particulate matter; polycyclic aromatic hydrocarbons; pollution characteristics; source apportionment; health risk assessment
- From: Journal of Environmental and Occupational Medicine 2026;43(9):1116-1122
- CountryChina
- Language:Chinese
- Abstract: Background Polycyclic aromatic hydrocarbons (PAHs) are significant organic components of PM2.5 and exhibit carcinogenic and mutagenic properties. Long-term exposure to high level of atmospheric particulate matter and particle-bound PAHs may contribute to the burden of environmentally related diseases in China. Objective To characterize PM2.5 concentrations and PM2.5-bound PAHs in three districts of Guangzhou from 2016 to 2024, and to assess the incremental lifetime cancer risk (ILCR) associated with inhalation exposure to PAHs among different population groups. Methods PM2.5 samples were collected monthly from the 10th to the 16th day of each month at rooftop monitoring sites on office buildings in Yuexiu, Conghua, and Panyu districts between 2016 and 2024. PM2.5 concentrations were measured, and 16 priority PAHs were quantified using high-performance liquid chromatography (HPLC). Seasonal and regional variations in PM2.5 and PAH concentrations were analyzed using the Kruskal-Wallis test. Potential PAH sources were identified using diagnostic ratio analysis and principal component analysis (PCA). The ILCR model was employed to estimate inhalation-related cancer risks for different population groups. Results From 2016 to 2024, the annual median PM2.5 concentrations in Guangzhou were 51.0, 46.0, 45.0, 41.5, 31.0, 32.0, 30.0, 26.0, and 37.5 μg·m−3, respectively, showing an overall declining trend. PM2.5 concentrations varied significantly by season, following the order of winter > spring/autumn > summer (H=475.341, P < 0.001). Spatially, PM2.5 concentrations were highest in Yuexiu, followed by Panyu and Conghua (H=36.226, P < 0.001). The annual median PAH concentrations were 3.95, 4.22, 3.73, 3.13, 2.54, 2.16, 2.78, 2.36, and 1.75 ng·m−3, respectively. PAH concentrations showed a similar seasonal pattern (winter > spring/autumn > summer; H=320.392, P < 0.001). However, their spatial distribution differed from that of PM2.5: Conghua > Panyu > Yuexiu (H=55.938, P < 0.001). Diagnostic ratios and PCA indicated that the major sources of PAHs were traffic-related emissions (gasoline and diesel combustion) and coal combustion, with additional contributions from petroleum volatilization and biomass burning. Benzo[a]pyrene (BaP) toxic equivalent concentrations declined over time and remained below the Chinese standard limit of 1 ng·m−3 after 2018. The median inhalation-related ILCRs were 0.094×10−6 for children, 0.035×10−6 for adolescents, and 0.293×10−6 for adults. Conclusion From 2016 to 2024, PM2.5 and PM2.5-bound PAH pollution levels in Guangzhou generally declined. Suburban areas had the lowest PM2.5 concentrations but the highest PAHs concentrations. Both PM2.5 and PM2.5-bound PAHs exhibited significant seasonal variations, with the highest levels in winter and the lowest levels in summer. The primary sources of PAHs were vehicular emissions and coal combustion, and PAHs posed no significant carcinogenic risk to the study population.
