上海市地表灰尘中PAHs分布特征与溯源

Sixteen priority control polycyclic aromatic hydrocarbons (PAHs) in road dust from central urban areas in Shanghai were quantitatively analyzed by GC-MS. The results indicate that the total PAH concentrations over the investigated sites ranged from 1.13 μg/g to 12.02 μg/g with an average of 5.97 μg/g. The highest concentration was recorded at traffic zone, while the lowest one was found at green park area. High-molecular-weight compounds (4-5 rings PAHs) were significantly dominant in the total mass of PAHs, and accounted for 66.29% to 78.61%. The most abundant PAHs congeners were Fluoranthene, Phenanthrene, Pyrene, Chrysene. Diagnostic ratio analysis showed that the road dust PAHs were mainly from the vehicle emissions, and partly derived from combustion of coal and coke. The concentration of benzo[a]pyrene equivalent (BaPeq) varied from 0.10 μg/g to 1.09 μg/g. The six highly carcinogenic PAH species (BaA, BaP, BbF, BkF, DBA, and IcdP) accounted for more than 60% of the total BaPeq concentration. Thus, the toxicity of PAHs in road dust was highly associated with high-molecular-weight compounds.