某焦化企业周边儿童重金属经口综合暴露健康风险

针对焦化企业开展的研究多关于企业工艺流程、污染物排放特征、周边环境有机物污染特征等方面，鲜有关注企业周边人群的重金属暴露及其健康风险的问题，本研究以我国北方某焦化企业为案例区，以当地儿童为研究对象，基于环境暴露行为模式问卷调查和现场实地样品的采集分析，探讨饮用水、土壤和食物介质中5种重金属（Pb、Cd、Cr、Ni和As）的污染特征，并分析儿童经口途径对饮用水、土壤和食物中重金属的暴露和健康风险水平.研究结果表明，焦化企业周边环境污染尚不突出，但儿童经口综合暴露的非致癌风险水平为0.74~6.30，是可接受风险水平的1~6倍，非致癌风险主要来自食物As暴露.儿童致癌风险水平为1.76×10^-4~7.75×10^-3，是可接受最高风险水平（1.0×10^-4）的几倍至几十倍，且主要归因于Cr经食物的暴露.本研究表明食物的经口暴露是各重金属经口综合暴露的主要途径，占经口综合暴露量的90%以上；焦化企业周边环境重金属污染虽不严峻，但可能会当地儿童带来严重的健康风险，需引起重视.

Health risks of cumulative oral exposure to heavy metals for children living around a coking enterprise

At present, the researches on coking enterprise are mostly focused on technological process, emission characteristics of pollutants, organic pollution in surrounding environment and so on. However, few studies concerned on the exposure and health risks to heavy metals for the population living in the vicinity of coking enterprise. Thus, this study selected a typical coking plant in north China as a model and recruited the local children as subjects. On the basis of environmental related exposure behavior patterns questionnaire survey and field investigation on sample collection and analysis, it explored the pollution status of five heavy metals (Pb、Cd、Cr、Ni and As) in environmental media including drinking water, soil and food, as well as the exposure dose and health risk to the metals via the environmental media through oral exposure. The results showed that the surrounding environment was not heavily polluted by heavy metals. However, the children's cumulative non-carcinogenic risks from various exposure pathways were in the range of 0.74 to 6.30, which was up to 6 times higher than the acceptable level (1), and was attributable to As exposure from food ingestion. The carcinogenic risks was 1.76×10^-4~7.75×10^-3, which was several to dozens of times higher than the acceptable level (1.0×10^-4), and mainly from Cr exposure due to food ingestion. This study indicated that food ingestion was the main pathway for total oral exposure dose, accounting for more than 90% to the total oral exposure dose. It highlighted that although the surrounding environment of coking plant was not heavily contaminated by heavy metals, it would cause severe potential health risks to local children, which need to be paid more attention.