西北典型河谷城市儿童铅暴露特征、来源与健康风险

Lead Poisoning (LP)in children due to lead exposure is becoming a global problem in public health.The character, source and risk of lead exposure to children through multimedium and multipathway contact in the regional area are the hotspot in environment health research.However,the quantitive analysis of lead exposure to children has not been well documented.Based on our previous researches,in this current research, we would choose the typical valley cities in northwestern China as the research field,and choose less than 6 children with different age and different ethnic as our research target. The quantitive analysis of lead exposure to children via mutimedium and multipathway is the core and objective of my whole research.According to the research proposal,the lead concentration distributing in urban soil,urban dust,air,drinking water and children meal would be initially evaluated by instrument analysis technique, and also monitored lead content in children blood by clinical examination method. Combining the lead isotopic ration determined by ICP-MS technique,the source of lead exposure to children would be discriminated. Consequently, the relationship between lead in multimedium environment and children blood lead would be quantitively identified. Integrating the survey and statistic of children's behavior and individual exposure monitoring, the exposure factors of children related to ingestion, inhalation and dermal contact would be proposed, then, the exposure level through above three multipathway would be quantitive calculated according to the exposure factors introduced. Finally, the risk of lead pollution in blood and lead exposure to children would be assessment with GIS techniques and USEPA models. The project will provide the scientific references to set up the children's exposure factor data and environmental qulity standards, and also to forecast, prevent and defend the lead exposure to children in China.

环境铅暴露致儿童铅中毒已成为全球性的重大公共卫生问题。在区域尺度下,儿童多介质-多途径铅暴露特征、来源与风险是目前研究的核心和尚待解决的问题，也是环境健康等交叉学科的前沿热点和长期关注的焦点。本项目结合课题组前期研究结果，以西北典型河谷城市为研究区域，以≤6岁不同年龄与民族儿童为研究对象，以儿童多介质多途径铅暴露定量分析为核心，运用环境监测与临床检验技术，分析环境介质土壤、灰尘、大气、饮用水及儿童膳食中铅污染与儿童血铅水平；利用铅同位素技术，解析儿童血铅污染的主要暴露途径和来源,阐明多介质环境铅暴露与儿童血铅定量关系及特征。结合儿童行为模式调查和个体暴露监测，建立儿童呼吸、手口和皮肤的暴露参数，确定儿童多途径铅暴露量；采用GIS与USEPA铅暴露风险评价法，评价预测儿童血铅污染与铅暴露的区域风险。为我国区域环境质量标准制定、儿童暴露参数建立、铅暴露风险评价、预警与综合防控提供科学理论依据。

0-6岁儿童铅暴露是我国西部儿童健康领域突出的新问题，在区域尺度下,低幼儿童多介质-多途径铅暴露是目前尚待解决的科学问题。课题组以多介质环境铅与0-6岁儿童多途径铅暴露为核心，踏足2600多公里的西部典型河谷型城市西安、榆林、延安、兰州、西宁、乌鲁木齐，展开了野外与入户调研、采集3825个样品与分析、暴露分析与风险预警等研究。系统调查了西部0-6岁儿童环境铅暴露，阐明了城市土壤铅与儿童血铅定量关系特征；探索了多介质铅等多元素污染特征与环境来源；明确了0-6岁儿童多介质环境铅等元素暴露途径与暴露剂量；解析了0-6岁儿童血铅污染与暴露来源；评估了0-6岁儿童多介质-多途径铅暴露风险；预测了区域0-6岁儿童血铅；探索了铅环境地球化学过程与城市污染修复新方法。研究建立了西部典型河谷型城市多介质环境铅等多元素的赋存清单和城市特征污染物；完善了基于重金属生物有效性和毒性系数的生态风险评价模型；明确了环境中细颗粒物是引起儿童血铅水平升高的主要粒级组成，发现了赋存细颗粒组分的铅氧化物是儿童血铅污染的主要化学形态和物相；实现了西部河谷型城市0-6岁儿童血铅预警与风险调控；建立了西部河谷型城市多介质环境铅与多途径0-6岁儿童暴露参数等关键基础数据；有效地解决了关键性科学问题，全面完成了研究计划任务，达到了预期的目标，取得了创新性成果。项目先后发表学术论文30多篇，出版科学研究专著1部、组织国际环境研究与公众健康杂志专题1期；举办环境与健康国际会议3次和环境与健康国际暑期学校2次；参加学术会议学术报告15次；开展“儿童铅暴露风险调控与儿童健康保育”讲座近10场；获陕西省科学技术奖等3次；培养近20名博士硕士研究生；获批陕西省污染暴露与生态环境健康国际联合研究中心、陕西师范大学青年创新研究团队和项目集群。研究成果为西部河谷型城市区域环境质量基准的建立、低幼儿童铅暴露预警与流行病综合防控、生态健康城市建设与污染综合治理提供重要的科学理论基础和技术支撑。