典型岩溶区土壤和地下水中多环芳烃的分布特征及健康风险研究

以重庆市典型岩溶槽谷为研究区，采集其地下河流域内的土壤和地下水样品，分析了16种优控多环芳烃（PAHs）的含量、时空分布特征及致癌、非致癌健康风险.结果表明，土壤和地下水在不同样点间的PAHs含量及健康风险差异明显，与国内外其它地区相比，青木关和南山流域内土壤和地下水PAHs的污染水平较低，两地下河流域内土壤PAHs的组成以高环为主，地下水中则以低环为主，土壤PAHs的健康风险值为5.53×10^-8~4.57×10^-7，整体处于低致癌风险水平，其中，二苯并a，h]蒽（DahA）的致癌风险最高，贡献率达80%以上；地下水PAHs的健康风险值为5.83×10^-8~1.32×10^-6，经口摄入途径的致癌风险水平较高.南山地下水样点间健康风险值波动比较大，受点源污染影响明显，其地下水的健康风险已超过可接受水平（1.0×10^-6）.

Distribution characteristics and health risks of PAHs in soils and groundwater in typical Karst areas

In this paper, soil and groundwater samples were collected from the typical Karst valleys in Chongqing.The contents, temporal and spatial distribution characteristics, carcinogenic and non-carcinogenic health risks of 16 PAHs in soil and groundwater samples were analyzed.The results showed that the content and health risk of soil and groundwater were significantly different in different sampling sites.Compared with other regions, the pollution level of PAHs of soil and groundwater in Qingmuguan and Nanshan catchments was lower.PAHs in soil in this study were dominated by high rings, while those in groundwater were dominated by low ring.The range of health risk values of PAHs in soil in this study is from 5.53×10^-8 to 4.57×10^-7, and the level of carcinogenic risk was low.DahA has the highest carcinogenic risk and contributes more than 80%.The range of the health risk value of PAHs in groundwater is from 5.83×10^-8 to 1.32×10^-6, the carcinogenic risk level by drinking water route is higher.The health risk values in Nanshan groundwater samples fluctuates greatly, which is obviously affected by point source pollution.The health risk of groundwater has exceeded the acceptable level (1.0×10^-6).