黄河全流域岸边表层土壤中PAHs的分布、来源及风险评估

为研究黄河流域表层土壤的多环芳烃（PAHs）污染水平，于2015年5月期间采集了39个黄河全流域岸边表层土壤样品.研究了土壤中∑₂₅PAHs和∑₇carc PAHs的空间分布特征，利用同分异构体比值法和主成分分析法对其进行来源解析，并采用BaP毒性当量和超额终生癌症风险增量模型（ELCR）对多环芳烃进行风险评估.结果表明，黄河流域表层土壤样品中∑₂₅PAHs浓度范围为18.23~6805.49ng/g，均值为343.764ng/g；∑₇care PAHs含量为2.23~2796.34ng/g，均值为126.6ng/g.PAHs含量整体趋势为中上游高于下游，多数土壤样品中Ant/（Ant+Phe）<0.1，0.2-6~10^-4之间，处于潜在风险水平.享堂ELCR值为10^-3，呈现较高健康风险水平.

Distribution,source and risk assessment of PAHs in surface soil of the Yellow River Basin

The contamination status of polycyclic aromatic hydrocarbons (PAHs) and the spatial distribution of ∑₂₅ PAHs and ∑_7carc PAHs were investigated based on 39 surface soil samples collected in May 2015 from the Yellow River Basin. The sources of PAHs were obtained by the isomer ratio method and principal component analysis method, and the health risk assessment of PAHs was evaluated by the BaP toxic equivalent and the excess lifetime risk model for cancer (ELCR). The results showed that the concentrations of mesenteric twenty-five PAHs in the surface soil ranged from 18.23 to 6805.49ng/g with an average value of 343.764ng/g; and the concentration of ∑₇ care PAHs ranged from 2.23 to 2796.34ng/g with an average value of 126.6ng/g. In general, the concentration of PAHs was higher in the middle and upper stream areas than in the downstream areas. In the majority of samples, we found that Ant/(Ant+Phe)<0.1, 0.2-6~10^-4, a level having potential health risks. While the value of ELCR in Xiangtang was higher at 10^-3, a level posting relatively high health risks.