Contamination Characteristics and Risk Assessment of Polycyclic Aromatic Compounds in Surface Dust of Suntuan Mining Area in Huaibei

Abstract

The Suntuan mining area of Huaibei is a typical coal resource mining base in the Huainan-Huaibei areas in North China. Previous environmental studies related to surface dust in coal mining areas mainly focused on heavy metals and water-soluble ions, with little research on polycyclic aromatic compounds (PACs). In this study, gas chromatography-triple tandem quadrupole mass spectrometry (GC-MS/MS) was used to determine the contents of 16 parent polycyclic aromatic hydrocarbons (16PAHs), alkyl polycyclic aromatic hydrocarbons (aPAHs), and some oxygenated polycyclic aromatic hydrocarbons (OPAHs) in surface dust from the Suntuan mining area and surrounding environment. The results showed that the ΣPACs concentration range of surface dust in the Suntuan mining area was 283.8-36852.5 μg·kg-1 (mean:4114.2 μg·kg-1). ΣaPAHs (mean:2593.8 μg·kg-1) was 2.4 times higher than Σ16PAHs (mean:1074.9 μg·kg-1), which was the main contributor to PAC pollution. The composition of 16PAHs and aPAHs in surface dust was dominated by low molecular polycyclic aromatic hydrocarbons. The average OPAH content was 445.6 μg·kg-1. At the same time, PAC pollution was mainly concentrated around the mining area and near the road of a coal gangue landfill. Based on the positive matrix factor (PMF) analysis, it was inferred that the study area was mainly affected by petroleum sources, followed by coal and biomass combustion, and traffic sources and petroleum product leakage accounted for a relatively small proportion. Based on the ratio and distribution pattern of 16PAHs and aPAHs, it was inferred that when Σ16PAHs/ΣPACs<0.25, it was mainly polluted by the coal mining area. The results of PMF combined with lifetime carcinogenic risk (ILCR) showed that there were potential carcinogenic risks for children near the study area, mainly from coal and biomass burning and coal mining. There are many coal mining areas in Huaihe River Basin in China. The results of this study can provide reference for pollution prevention and control of PACs in these coal mining areas.