Profiles and source apportionment of PAHs in particulate matter from resuspended dust in coal mining areas: Implications for atmospheric pollution

Abstract

This study collected particulate matter (PM) samples from 20 dust samples in the Zhubai mining area, Linyi City, Shandong Province, China, using a laboratory resuspension particle sampling system. Polycyclic aromatic hydrocarbons (PAHs) in PM_2.5, PM₁₀, and total PM (PM_total) were quantified using GC/MS/MS, identifying 32 aromatic compounds. PAH concentrations decreased in the order of PM_2.5 (66.46 ± 43.56 μg/g), PM₁₀ (19.96 ± 10.95 μg/g), and PM_total (15.13 ± 12.09 μg/g), with levels significantly higher than previous reports in soil/dust systems. PM_2.5 and PM₁₀ profiles were similar, dominated by low-ring PAHs like naphthalene and phenanthrene, while high-ring PAHs associated with combustion appeared at very low levels. PM_total differed markedly, with reduced naphthalene and increased proportions of combustion-related PAHs like fluoranthene, chrysene, and benzo[g,h,i]perylene. The coefficient of divergence (CD) suggested that particle size impacts PAH composition, indicating that distinguishing fine and coarse particles is crucial for accurate pollution assessment. Diagnostic ratio characteristics revealed mixed PAH sources, emphasizing the need to consider local pollution sources for accurate source apportionment. The Positive Matrix Factorization (PMF) model identified three primary PAH sources: coal/coal gangue particles (42.2%), coal/biomass combustion (34.6%), and traffic emissions (23.3%). Surface dust from coal mining areas, influenced by unburned coal and coal gangue, likely significantly contributed to atmospheric particulate matter once resuspended.