Abstract:
To investigate the levels, compositions, distributions and sources of PAHs in the surface soil of Altay, Xinjiang. Totally 14 samples collected from the surface soil in October 2018 were analyzed for 16 USEPA priority PAHs by gas chromatography-mass spectrometry (GC-MS). The total PAHs concentrations ranged from 3.48 to 103.81 ng·g
-1, with an average of 32.24 ng·g
-1, which were mainly composed of three-rings and four-rings PAHs. In addition, the total concentrations of seven carcinogenic PAHs ranged from 0.32 to 50.95 ng·g
-1, with an average of 11.20 ng·g
-1. Lower levels of PAHs contamination were found in surface soil of study area, and there was no significant correlation between PAHs level and altitude (
r=-0.471,
P=0.668). The results of PAHs isomeric diagnosis ratios show that the main sources of soil PAHs in Altay Area were fossil fuels and biomass combustion, and vehicle emissions contributed more to PAHs. Three sources including vehicle emissions, coke ovens and coal combustion, and biomass combustion were quantified by the PCA-MLR model, accounting for 62.8%, 28.2% and 9.0% of the total PAHs, respectively. Compared with emission contribution sources in 2012 of Xinjiang, the vehicle emissions, coke ovens and coal emissions showed an increasing trend.