Exposure Assessment of Children & Metals in Mining Waste

儿童暴露评估

• 批准号: 6968757
• 负责人: James P Shine
• 金额: $ 6.01万
• 依托单位: HARVARD SCHOOL OF PUBLIC HEALTH
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-01 至 2009-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6968757
• 关键词: Native Americans; X ray spectrometry; air sampling /monitoring; children; clinical research; culture; dust; environmental exposure; gene expression; human subject; lead poisoning; manganese; metal poisoning; microarray technology; minings; neurotoxicology; particle; sulfides; water sampling /testing

Project #2 explores the transport and fate of metals from mine wastes (chat) that could potentially lead to adverse exposure in children in communities surrounding the Tar Creek Superfund Site. Although metals in mining waste have been thought by some to be relatively unavailable for geochemical mobilization or biological uptake (due to interactions with reactive sulfides), we hypothesize that reactions releasing metals from the sulfides may make metals from mining waste more bioavailable than expected. They may also favor the release of some metals (such as Zn and Cd) over others (such as Cu and Pb). Thus, the mixture of metals to which children are exposed may be very different from the mixture of metals present in the parent chat. In addition, metals that have mobilized off the chat piles into other exposure media such as soil, water, airborne particulates and indoor dust, may have a higher relative bioavailability when compared to parent waste material. We propose to test this hypothesis, and determine whether the types and bioavailability of metals to which children are exposed can be better understood through a more sophisticated consideration of the underlying geochemistry of metals in mine wastes. Specifically, we will study which metals are enriched in down-gradient exposure media relative to metals in chat, and use sequential extraction techniques (and X-Ray Absorption Spectroscopy) to demonstrate that metals in these down-gradient media have a higher relative bioavailability. In conjunction with Project #1, we will use these data to conduct a nested case-control study to examine the extent that environmental and behavioral factors, including diet and activity patterns, may explain differences in blood levels of Pb and Mn in children from the Tar Creek area with high and low levels of Pb and Mn in their blood. We will use the samples we have collected in this project to supply the animal studies (Projects 3 and 4) with well characterized exposure material with respect to the concentrations and potential bioavailability of metals within each media. Finally, in parallel with the exposure assessment, we will conduct microarray experiments and assess their utility as part of an overall exposure/adverse health outcome assessment.

项目2探讨了来自矿山废物(CHAT)的金属的运输和命运，这可能会导致焦油溪超级基金场地周围社区的儿童受到不良影响。虽然一些人认为采矿废物中的金属相对不能用于地球化学活化或生物吸收(由于与活性硫化物的相互作用)，但我们推测，从硫化物中释放金属的反应可能会产生金属。 从采矿废物中获得的生物利用率比预期的要高。它们还可能有利于某些金属(如锌和镉)的释放，而不是其他金属(如铜和铅)。因此，儿童接触的金属混合物可能与父母聊天中存在的金属混合物非常不同。此外，与母体废物相比，从聊天堆中转移到其他暴露介质中的金属，如土壤、水、空气颗粒物和室内粉尘，可能具有更高的相对生物利用度。我们建议检验这一假设，并确定是否可以通过更复杂地考虑矿山废物中金属的基本地球化学来更好地了解儿童接触的金属的类型和生物可利用性。具体地说，我们将研究相对于ChAT中的金属，哪些金属在下行介质中富集，并使用顺序提取技术(和X射线吸收光谱)来证明这些下行介质中的金属具有更高的相对生物利用度。结合项目1，我们将利用这些数据进行嵌套病例对照研究，以考察环境和行为因素(包括饮食和活动模式)可能在多大程度上解释焦油河地区血液中铅和锰含量高低的儿童的血液铅和锰水平的差异。我们将使用我们在本项目中收集的样本为动物研究(项目3和4)提供关于每种介质中金属的浓度和潜在生物可利用性的详细描述的暴露材料。最后，在进行暴露评估的同时，我们将进行微阵列实验，并评估其效用，作为整体暴露/不良健康后果评估的一部分。