Exposure Assessment of Children & Metals in Mining Waste

儿童暴露评估

• 批准号: 7063367
• 负责人: James P Shine
• 金额: $ 6.23万
• 依托单位: HARVARD SCHOOL OF PUBLIC HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7063367
• 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）的金属的运输和归宿，这些金属可能会导致焦油溪超级基金场地周围社区的儿童受到不利影响。虽然有些人认为采矿废物中的金属相对来说不可用于地球化学动员或生物吸收（由于与活性硫化物的相互作用），但我们假设从硫化物中释放金属的反应可能使金属 比预期的生物利用度更高。它们也可能有利于某些金属（如Zn和Cd）的释放，而不是其他金属（如Cu和Pb）。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，与母体废物材料相比，从聊天堆移动到其他接触介质（如土壤、水、空气中的颗粒物和室内灰尘）的金属可能具有更高的相对生物利用度。我们建议测试这一假设，并确定是否可以更好地了解儿童接触的金属的类型和生物利用度通过更复杂的考虑矿山废物中的金属的基本地球化学。具体来说，我们将研究相对于聊天中的金属，哪些金属在向下梯度暴露介质中富集，并使用顺序提取技术（和X射线吸收光谱法）来证明这些向下梯度介质中的金属具有更高的相对生物利用度。结合项目#1，我们将使用这些数据进行巢式病例对照研究，以检查的程度，环境和行为因素，包括饮食和活动模式，可以解释的铅和锰的血液中的铅和锰的儿童从焦油溪地区与高和低水平的铅和锰在他们的血液中的差异。我们将使用我们在本项目中收集的样品为动物研究（项目3和4）提供关于每种介质中金属浓度和潜在生物利用度的充分表征的暴露材料。最后，与暴露评估平行，我们将进行微阵列实验，并评估其效用作为整体暴露/不良健康结果评估的一部分。