In order to evaluate health risk of the exposure of typical local inhabitants of Nandan to heavy metals via con-sumption of vegetable, impacts of mining activities on content of heavy metals in soil and vegetable in Dachang, Chehe, and Changlao and in Liuzhai as check were investigated. Through a consecutive 3-day household diet survey, the data of vegetable consumption rate were obtained. And at the same time, soil samples from 37 vegetable fields and 166 vegetable samples were collected for analysis of contents of As, Pb, Cd, Cu, Zn and Sb. In addition, the potential health risk of the exposure of local people to heavy metals via consumption of the vegetable was assessed using the pollution index method and the data of intake of heavy metals. Results show that in terms of concentration of heavy metals in the soils and vegeta-bles, the four sites followed a decreasing order of Dachang>Chehe>Zhanglao>Liuzhai;the vegetables produced in mining-affected areas had about 5. 60%, 71. 1% and 32. 3% exceeding the criteria for As, Pb and Cd set, respectively, in the national standard for food safety while the vegetable produced in Liuzhai had 57. 1% and 37. 5%, exceeding the criteria for Pb and Cd, respectively;the adult inhabitants in Dachang and Chehe took in much more As, Pb, Cd, Cu, Zn and Sb via consumption of vegetables than those in Liuzhai did daily. The target hazard quotients ( THQ) of As, Pb, Cd and Sb in vegetable were all higher than that of Cu and Zn in the four areas, and the target cancer risk ( TR) of As in vegetable to individual human health reached 10. 64 × 10-5 and 10. 20 × 10-5 a-1 , respectively, in Dachang and Chehe, significantly higher than the criteria set in the standard (i.e. 10-6-10-4) of United States Environmental Protection Agency (USEPA) and the standard (i.e. 5×10-5) of International Commission on Radiological Protection (ICRP), which indicates that Pb and Cd are the major heavy metal elements posing health risks to health of the inhabitants in the mining area and that the inhabitants in mining concentrated areas are facing severe risks of exposure to heavy metals.%为评估"有色金属之乡"——南丹典型村庄常住居民蔬菜消费中重金属暴露风险,对矿业活动影响区大厂镇、车河镇和长老乡及对照区六寨镇典型村庄蔬菜和菜地土壤重金属含量进行调查.通过连续3d入户膳食调查获得蔬菜消费量数据,并采集37个菜地土壤样品及166个蔬菜样品,分析其As、Pb、Cd、Cu、Zn和Sb含量,通过污染指数法和重金属摄入量评估暴露接触的人体健康风险.结果表明,不同地区土壤与蔬菜中重金属含量由高到低依次为大厂镇、车河镇、长老乡和六寨镇;矿业影响区蔬菜As、Pb和Cd的超标率分别为5.60%、71.1%和32.3%,对照区蔬菜Pb和Cd的超标率分别为57.1%和37.5%;大厂镇和车河镇成人经蔬菜途径进入人体的As、Pb、Cd、Cu、Zn和Sb含量显著高于六寨镇;4个地区蔬菜As、Pb、Cd和Sb对应的目标危险系数均高于Cu和Zn.风险评价结果表明,大厂镇和车河镇蔬菜As的年健康风险分别为10.64×10-5和10.20×10-5 a-1,远高于国际放射防护委员会推荐的标准,表明居住在矿业密集区的居民面临较严重的重金属接触暴露风险,且显著高于对照区.
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