某化工厂铬渣堆场及周边土壤重金属污染风险评估研究

针对某搬迁化工厂铬渣堆场及周边土壤,分层分区采集样品分析重金属含量,从生态和人体健康角度对土壤Cr,Ni,Cu,As进行风险评估。结果表明土壤Cr、Cr(Ⅵ)污染较为严重,集中在第一(0 m~1.5 m)和第二层(1.5 m~3 m);Cu、As、Ni污染较轻,集中在第一层。生态风险评估表明随深度增加,潜在生态危害指数降低。生态风险顺序为CrNiAsCu。健康风险评估表明各层土壤均存在Cr(Ⅵ)致癌风险,其余重金属在第一和第二层存在可接受非致癌风险。

Risk Assessment of Heavy Metal Pollution in Soil Around Chrome Reside PollutedSite at a Chemical Plant

The distribution of heavy metals in soil around the chromium slag contaminated site at a chemical plant was investi-gated by collecting soil samples in different parts of layers. At the same time, a health risk assessment model and Hakanson＇s po-tential ecological risk assessment model were used to evaluate the soil quality based on contents of heavy metals （ Cr, Ni, Cu, As）.The results showed that Cr, Cr（ VI ）had reached the severity pollution level which mainly distributed on the first layer（0 - 1.5 m）and second layer （ 1.5 m - 3 m）. Ni, Cu and As were in minor pollution level which mainly distributed on the first layer.Hakanson＇s potential ecological risk index evaluation showed that the values of ecological risk index were decreasing while thedepth increased. The order for Hakanson＇s potential ecological risk indexofheavy metals were Cr 〉 Ni 〉 As 〉 Cu. The human riskassessment indicated that adults and childrenexposed to Cr（ VI ） in all layers would suffer carcinogenic risk. The hazard indices ofCr, Ni, Cu and As lessthanunity mean thatthenon - carcinogenicheahhrisk was acceptable.