Characteristics, Sources, and Risks of Polycyclic Aromatic Hydrocarbons in Topsoil and Surface Water from the Liuxi River Basin, South China

• Published in: Archives of environmental contamination and toxicology Vol. 78; no. 3; pp. 401 - 415
• Main Authors: Xie, Zhenglan, Gao, Lei, Liang, Zuobing, Chen, Jianyao, Li, Shaoheng, Zhu, Aiping, Wu, Yu, Yang, Zhigang, Li, Rui, Wang, Zhuowei
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.04.2020; Springer Nature B.V
• Subjects: basins; Carbon content; China; Coking; Correlation analysis; Earth and Environmental Science; Ecology; Ecotoxicology; Emissions; Environment; Environmental Chemistry; Environmental Health; Environmental Monitoring - methods; Fossil fuels; Fuel combustion; Geologic Sediments - chemistry; guidelines; Monitoring/Environmental Analysis; Organic carbon; particulate emissions; Pollutant deposition; Pollutants; Pollution; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Public health; Quality assessment; risk; Risk Assessment; River basins; Rivers; Rivers - chemistry; Soil - chemistry; Soil Pollutants - analysis; Soil quality; Soil Science & Conservation; Spatial distribution; Surface water; Topsoil; Total organic carbon; toxicity; Tributaries; Vehicle emissions; Water Pollutants, Chemical - analysis; Water pollution; watersheds; Wet deposition; China
• ISSN: 0090-4341; 1432-0703; 1432-0703
• DOI: 10.1007/s00244-020-00711-4

The concentrations, composition, sources, and risks of polycyclic aromatic hydrocarbons (PAHs) in topsoil and surface water of the Liuxi River basin, south China were analyzed in this study. The total concentrations of 16 PAHs ranged from 296.26 to 888.14 ng/g in topsoil and from 156.73 to 422.03 ng/L in surface water, indicating mild pollution. The PAHs in topsoil exhibited an even spatial distribution, suggesting that they originated primarily from dry and wet deposition of transported pollutants. The concentration of PAHs in surface water did not differ significantly geographically, but the concentrations of total, three-, and four-ring PAHs were significantly lower in the Liuxi River than in its tributaries. Three- and two-ring PAHs predominated in topsoil and surface water, respectively. A correlation analysis suggested that the total organic carbon content and pH exerted a negligible effect on the spatial distribution of PAHs in topsoil, and they may have common sources. Fossil fuel combustion (particularly vehicle emissions) and coking production were the dominant sources of PAHs in topsoil, whereas those in surface water were derived from a variety of sources. The total toxic equivalent concentrations of 16 PAHs in topsoil ranged from 3.73 to 105.66 ng/g (mean, 30.93 ng/g), suggesting that exposure to the basin’s topsoil does not pose a risk to the environment or public health according to the Canadian soil quality guidelines. A risk assessment revealed that the total PAH concentrations in surface water posed a low ecological risk.