宁夏北部农田重金属污染源解析及居民健康风险评估与时空预测研究

Heavy metal pollution in rural land of our country is a matter of concern which causes great threat to safety of agricultural product, eco-environmental security and human health. However, most studies focused on the more developed eastern region, for Ningxia province (more remote) there was no systematic and elaborate study. Hence in this survey, we focus on the farmland in northern area if Ningxia where heavy metal concentration is high, and evaluate human health for the residents in the area. Firstly, we investigate pollution status of heavy metals in crops and soil through field sampling survey. Furthermore we build a source list of heavy metals and analyze the source of heavy metals by isotope method, statistical analysis and GIS spatial analysis; secondly, we evaluate carcinogenic risk and non-carcinogenic risk by dietary survey of the resident and health risk assessment model, and analyze uncertainty by probability evaluation model to calculate the contribution of different exposure factor; lastly, we use situation prediction method combined with GIS spatial analysis method to do spatiotemporal forecasting and put forward pollution control and management countermeasures. The achievements of our survey will provide a reference for the prevention and repair of heavy metal, ensure health and reduce risks of residents in these areas, which will be of great importance theoretically and practically.

我国农村土地重金属污染对于农产品安全、生态环境安全和人类健康造成了极大的威胁，但是目前多数研究集中于东部较发达地区，对于较为偏僻的宁夏还没有系统详尽的研究。因此本项目对重金属背景值较高的宁夏北部农田及附近居民健康进行关注并进行系统评估。首先从大田采样调查着手，研究农田及作物中重金属的污染现状，建立重金属源清单，并通过同位素法、统计分析法以及地理信息系统（GIS）空间分析法进行重金属源解析；其次通过对居民的膳食调查，结合健康风险评估模型对居民基于重金属污染的致癌风险和非致癌风险进行评估，并通过概率评估模型进行不确定性分析，得到不同暴露因子的贡献率；最后通过情景预测法结合GIS空间分析法对研究区域进行时空预测并提出污染防治与管理对策。本项目的实施对宁夏北部农田重金属的防治修复提供依据，对保障居民健康以及降低风险提供数据支撑，在理论与实际应用上均具有重要的意义。

我国农村土地重金属污染对于农产品安全、生态环境安全和人类健康造成了极大的威胁，但是目前多数研究集中于东部较发达地区，对于较为偏僻的宁夏还没有系统详尽的研究。本项目对重金属含量较高的宁夏北部重点关注，完成了研究区域内农田、农作物及灌溉水中重金属现状调查及附近居民健康风险的系统研究。首先从采样调查着手，研究农田、作物及灌溉水中重金属的污染现状，对土壤进行生态风险评估，并通过同位素法、统计分析法以及地理信息系统（GIS）空间分析法进行土壤重金属源解析；其次通过对居民的膳食调查，结合健康风险评估模型对居民基于重金属污染的致癌风险和非致癌风险进行评估，并通过概率评估模型进行不确定性分析，得到不同暴露因子的贡献率；最后通过情景预测法结合GIS空间分析法对研究区域进行时空预测并提出污染防治与管理对策。本项目的实施对宁夏北部农田重金属的防治修复提供了依据，对保障居民健康以及降低风险提供了数据支撑。