某废弃化工场地重金属污染土壤健康风险评估

Health risk assessment of heavy metal contaminated soil in an abandoned chemical site

选择我国某废弃化工场地为研究对象,以《污染场地风险评估技术导则》等为理论基础,并参考国内外相关风险评价方法及选择适当的风险评估参数,对场地开展调查、布点采样分析与健康风险评估工作。结果表明:场地内个别点位明显存在砷、镉、钡重金属污染,其中砷暴露途径的致癌风险指数在10^(-6)以上水平,非致癌危害熵远高于1,对人体健康风险的贡献最大。研究认为,该场地在进行居住用地开发利用之前,必须针对某些污染点位进行土壤修复与综合治理,使风险降低到人体健康可接受水平。

The investigation and health risk assessments of soil polluted by heavy metals were conducted at the abandoned chemical site by using domestic and international risk assessment methods and basing on ＂Guidelines for Risk Assessment of Contaminated Sites＂. The results indicated that there were obviously heavy metal pollution of arsenic,cadmium and barium in several points of the site and only existed in the area above 4 m. Arsenic,of which the carcinogenic risk index from various exposure routes was above 10^（-6） and non-carcinogenic hazard quotient was much higher than 1,contributed the most to health risk. Therefore,it is necessary to carry out remediation and comprehensive treatment for some contaminated points for reducing the risk to an acceptable level of human health before site development.