城市老工业区土壤重金属污染状况与健康风险评价

Heavy Metals Contamination and Health Risk Assessment of Urban Soil in Old Industrial Area

本文对西部某老工业区土壤中As、Pb、Cr、Cd、Hg、Zn的含量、空间分布状况展开了研究,并依据《污染场地风险评估技术导则》对该老工业区的健康风险进行了评价。研究结果表明,该老工业区土壤重金属污染严重,6种元素与陕西土壤背景值相比超标100%,表明其不适宜作为居住用地开发。健康风险评价结果显示,As、Pb、Cr、Cd元素的非致癌风险值分别为3.83、1.7、1.94、1.09,均超过非致癌风险可接受值1,表明该老工业区对人们存在非致癌健康风险;对于致癌风险,As、Cr、Cd元素的致癌风险值远大于致癌风险边界值,分别超过致癌风险值的2个数量级(2.64×10-4)、4个数量级(1.94×10-2)、1个数量级(6.12×10-5),表示As和Cr已经达到了显著致癌风险的水平。

In this paper,concentration and spatial distribution of As,Pb,Cr,Cd,Hg and Zn in the soil of an old industrial area of western China is studied,and health risks of this old industrial area are evaluated based on ＂Risk Assessment of Contaminated Sites Technical Guidelines＂.The results show that the soil in this old industrial areas is heavily polluted by heavy metals,six elements of heavy metals are overweight 100% compared to background values in Shanxi province and it shows that this area is not fitted for residential land development.Health risk assessment results show that As,Pb,Cr,Cd elements values of non-cancer risk are 3.83,1.7,1.94 and 1.09 respectively,all exceeding the acceptable value 1,indicating that there exists non-carcinogenic health risk for people in the old industrial area; for As,Cr and Cd,the values of cancer risk are much greater than cancer risk boundary value,the cancer risk of As,Cr is at significant unacceptable level,is 2 orders of magnitude（2.64 × 10^-4）,4 orders of magnitude（1.94 × 10^-2） and 1 order of magnitude（6.12 × 10^-5） respectively.