家养狗生物标志及同位素指纹技术解析涉铅企业周边儿童铅暴露来源

Children are susceptible to lead exposure. With the frequent occurrence of children’s lead poisoning accidents, lead exposure of children living around lead-related manufactures has becoming an important environmental health issue. While, efficiently source apportionment of lead exposure could be critical to prevent the health risks of lead exposure. Although blood lead is regarded as the most representative biomarker of internal lead exposure, there is few researches focused on the methods of blood lead source apportionment, due to the difficulty of sample collection of children’s blood. Thus, the blood lead isotope-based source apportionment of children’s lead exposure needs more further studies, and the study on alternative biomarkers in identifying children’s lead exposure and pollution source could be of important and practical significance. In this study, the children and their household dogs living near a typical lead-related manufacture will be selected as target subjects. Combined with the methods and techniques including activity patterns survey, lead isotope technique, environmental exposure assessment models, multivariate regression analysis, the blood lead and lead isotope characteristics of children and household dogs would be analyzed, as well as the lead isotope characteristic of external environmental media and potential pollution sources. The exposure pathways and main pollution sources of children and household dog’s lead exposure then would be quantificational identified. Finally, explore whether blood lead isotope fingerprint characteristics of household dog could be applied to do source apportionment of children’s lead exposure, expecting to provide method and basis for the treatment of children's blood lead contamination incidents.

儿童是铅暴露的敏感人群，近年爆发的儿童血铅污染事件使涉铅企业周边儿童铅暴露成为一个重要的环境与健康问题，而有效识别铅暴露途径及污染源是防范铅暴露健康风险的关键。血铅虽被视为体内铅暴露最准确的生物标志物，然而因实际调查中人体血液样本难获取，鲜有关于儿童血铅污染源解析方法的研究。基于血铅同位素特征开展人群铅暴露及污染源解析有待深入研究，选择可替代的生物标志指示儿童血铅及其来源具重要的现实意义。本研究拟将典型涉铅企业周边的儿童及其家养狗为对象，结合环境暴露行为模式调查、铅稳定同位素指纹技术、环境暴露评价模型、多元数据回归分析等方法和技术，通过深入分析儿童和家养狗血铅及铅同位素指纹特征，环境外暴露介质及污染源铅的同位素指纹特征，定量识别儿童和家养狗血铅暴露的途径和来源，探讨基于家养狗血铅同位素指纹技术来解析涉铅企业周边儿童铅暴露及污染源的可行性，以期为儿童血铅污染事件的处理提供方法依据。

涉铅企业周边儿童铅暴露仍然是一个重要的环境与健康问题，而有效识别铅暴露途径及污染源是防范铅暴露健康风险的关键。血铅虽被视为体内铅暴露最准确的生物标志物，然而因实际调查中人体血液样本难获取，基于血液样本开展儿童铅暴露的来源解析实际研究及现场工作中受到一定限制，基于血铅同位素特征开展人群铅暴露及污染源解析有待深入研究，选择可替代的生物标志指示儿童血铅及其来源具重要的现实义。. 基于此，本研究选择铅锌冶炼区、燃煤区和无工业活动的对照区为研究案例区，以案例区的儿童及其家养狗为研究对象，开展儿童和家养狗铅暴露行为模式的调查，建立并完善家养狗血铅同位素指纹特征分析方法；通过深入分析儿童和家养狗血铅及铅同位素指纹特征，环境外暴露介质及污染源铅的同位素指纹征，分别基于铅同位素指纹技术和暴露评价模型解析儿童、家养狗血铅污染来源；探索家养狗血铅暴露及污染源识别指示儿童铅暴露及其污染来源，探讨基于家养狗血铅同位素指纹技术来解析涉铅企业周边儿童铅暴露及污染源的可行性及方法模型。. 结果表明，燃煤区和对照区儿童、家养狗血铅水平分别为8.51±1.04 µg/dL和3.80±0.54 µg/dL，8.29±1.13 μg/dL和 3.60 ± 0.49 µg/dL；冶炼区家养狗血铅水平为17.59±2.53μg/dL，各地区儿童与家犬的铅浓度无显着差异。冶炼区、燃煤区和对照区家养狗血铅207Pb/206Pb同位素特征分别为 0.8694±0.0046，0.8499±0.0052 和0.8381±0.0055。燃煤区与对照区儿童血铅同位素特征分别为0.8501±0.0052和0.8379±0.0056 。儿童和家养狗血铅同位素特征三个地区间差异较大，但同一地区家养狗血铅与儿童同位素比值特征具有极显著的相关性(p<0.01)。通过对潜在污染源(矿渣、矿石、煤、油漆)与血液样品的同位素特征比较，发现狗血铅污染源与儿童血铅污染源一致。矿石冶炼和燃煤是冶炼区家养狗和儿童铅暴露的主要来源，燃煤排放是燃煤区和对照区家养狗和儿童铅暴露的主要来源。研究表明，狗的血铅浓度可能不是评估儿童血铅水平较好的替代指标，但家养狗的血铅同位素测量可以作为确定儿童铅暴露来源的一种替代方法。本研究为家养狗成为人类铅暴露的哨兵提供了相关证据，并为环境卫生管理中儿童铅暴露的源解析提供了可替代的方法。