内蒙古乌达煤田是中国重要的煤炭基地，也是煤火（煤层与煤矸石自燃）最严重的地区。本研究采用气相色谱-质谱联用技术，测试了乌达区表层土壤中多环芳烃（PACs）的浓度，并分析了煤矿、煤火、农业和背景区域的特征、分布、来源和健康风险。煤矿和煤火区域土壤PACs污染严重，平均浓度分别为9107和3163 µg/kg，远高于农业区域（1232 µg/kg）和背景区域（710 µg/kg）。烷基多环芳烃（APAHs）是这些PACs中占主导地位的污染物，占60-81%。烷基萘和烷基菲是APAHs中的主要污染物，占总量的80-90%。此外，使用正矩阵分解方法得出，主要的PAC来源是岩石源、煤炭和生物质燃烧、煤火和车辆排放。最后，根据16种PAH的癌症风险值，仅煤矿区域存在潜在的癌症风险。然而，这个结论缺乏对APAHs的风险评估，低估了实际风险。本研究的结果提高了对煤火和周边区域PAC污染的理解，为环境和健康风险调查提供了参考。© 2023作者，独家许可给Springer Nature B.V.。

The Wuda coalfield in Inner Mongolia is a vital coal base in China, and it is the hardest-hit area for coal fires (spontaneous combustion of coal seams and coal gangue). Using gas chromatography-mass spectrometry, this work tested the concentration and analyzed the characteristics, distribution, sources, and health risks of polycyclic aromatic compounds (PACs) in the surface soil of the Wuda District, including the coal mine, coal fire, agricultural, and background areas. The soil of coal mine and coal fire area were heavily polluted with PACs, with mean concentrations of 9107 and 3163 µg kg-1, respectively, considerably higher than those in the agricultural (1232 µg kg-1) and background areas (710 µg kg-1). Alkyl polycyclic aromatic hydrocarbons (APAHs) were the dominant pollutants among these PACs, accounting for 60-81%. Alkyl naphthalenes and alkyl phenanthrenes are the primary pollutants in APAHs, accounting for 80-90% of the total amounts. Additionally, using the positive matrix factorization method, it can be concluded that the primary PAC sources are petrogenic sources, coal and biomass combustion, coal fires, and vehicle emissions. Finally, according to the cancer risk values of 16 PAHs, only the coal mine area showed a potential cancer risk. However, this result lacks a risk assessment of APAHs and underestimates the actual risk. The results of this study improved the understanding of PAC pollution in coal fire and surrounding areas and provided a reference for environmental and health risk investigations.© 2023. The Author(s), under exclusive licence to Springer Nature B.V.