上海市公园绿地玻璃表面多环芳烃污染特征及源解析

In order to study the pollution characteristics and pollution sources of polycyclic aromatic hydrocarbons (PAHs) on the glass surfaces in the Shanghai park green space， the mass concentrations of 16 types of PAHs were determined by gas chromatography-mass spectrometry (GC-MS)，the seasonal distribution，composition characteristics and potential pollution sources of PAHs on the glass surface were analyzed. In addition，the toxic equivalent factors (TEFs) were used to analyze the toxic equivalents of PAHs on the glass surface. The results showed that the area-normalized mass concentrations of PAHs on the glass surface ranged from 83.6 to 1689.6 ng·m⁻²，with the following characteristics: summer (599.7 ng·m⁻²) > autumn (533.1 ng·m⁻²) > spring (464.2 ng·m⁻²) > winter (351.4 ng·m⁻²). The seasonal deviations in the PAH compositions were evident，such that the proportion of 4-ring PAHs was maximized in spring (43%) and winter (42%). In comparison，the amounts of 2+3 rings accounted for the highest proportion in autumn (57%) and summer (46%). The strong correlation between BghiP and T-PAHs indicated that automobile exhaust gases were the primary contributing source of PAHs on the glass surface. Furthermore，the isomer ratios indicated that the primary pollution sources， including automobile exhaust gases and dust sources (dust fall and exposed topsoil)，were relatively unchanged in different seasons. The mass concentrations of seven carcinogenic PAHs after mass-normalization ranged from 58.3 ng·g⁻¹ to 1311.8 ng·g⁻¹，while the concentration of TEQ followed the order of summer (466.6 ng·g⁻¹) > spring (361.0 ng·g⁻¹) > autumn (262.9 ng·g⁻¹) > winter (214.6 ng·g⁻¹). BAP，DahA and B[b+k]F were the main carcinogenic monomers of PAHs，accounting for 80%—91% of the TEQ concentration.