Core--Lead exposure pathways, biomarkers, health effects, & phytoremediation

生活在俄克拉何马州焦油溪超级基金遗址（TCSS）地区的人们高度暴露于铅污染的采矿废物（“chat”）中。大约42%的居民是美国印第安人后裔。初步研究发现，该地区几个城镇中有很高比例（25-63%）的幼儿血铅超过10马克杯/分升，并确定接触“聊天”是血铅水平升高的一个主要独立风险因素。1997年，我们开始与俄克拉何马州东北部一个社区组织的成员合作，致力于解决这些问题（“地方环境行动要求”[L.E.A.D.]）[机构，公司]根据社区关注的问题和优先事项，以社区为基础开展铅接触途径、铅剂量的生物标记、行为影响和植物修复策略的综合社区研究。在本研究的流行病学部分，我们将测量位于TCSS的四所中学的六年级和七年级学生的骨铅水平（使用k -x射线荧光仪）和血铅水平。这些措施将与爱荷华州基本技能测试（一项所有五年级和七年级学生都必须参加的评估工具）的分数以及由家长、老师和学生自己管理的儿童行为检查表的评分有关。我们将验证累积的铅负担是导致认知和行为结果不良的主要风险因素的假设，这些结果在该社区非常普遍。与此同时，我们将调查塔尔溪超级基金遗址的原生植被，以确定植物物种多样性和空间分布，同时测量植物组织和土壤中的铅含量。我们的分析将确定本地植被模式是否预测植物修复过程（植物和土壤铅污染物的相互作用）。我们将整合这些数据，并收集水文地质、园艺和气候因素的新数据，以设计一个基于社区的植物修复计划模型。我们将测试植物修复可以降低目标地区高土壤铅浓度的假设。最后，我们将利用流行病学研究产生的骨和血铅水平数据，对居住在“闲谈”堆附近的高铅负担和低铅负担个体进行目标暴露评估随访研究，并检查空间、生态、家庭和行为因素，这些因素可以预测儿童在高污染环境中是否会出现高铅负担或低铅负担。

Individuals living in the Tar Creek Superfund Site (TCSS) area of Oklahoma are highly exposed to lead-contaminated mining wastes ("chat"). Approximately 42% of residents are of American Indian descent. Initial studies have found high proportions (25-63%) of young children in several of the area's towns with blood leads exceeding 10 mug/dL and identified exposure to "chat" as a major independent risk factor for elevated blood lead levels. In 1997, we began working with members of a Northeast Oklahoma community group dedicated to addressing these issues ("Local Environmental Action Demanded" [L.E.A.D.] Agency, Inc.) To develop, based on community concerns and priorities, and integrated community-based study of lead exposure pathways, biological markers of lead dose, behavioral effects, and phytoremediation strategies. In the epidemiologic component of this study, we will measure bone lead levels (using a K-x-ray fluorescence instrument) and blood lead levels among 6th, and 7th graders at four middle schools located in the TCSS. These measures will be related to scores on the Iowa Test of Basic Skills, an evaluation instrument that all students are already required to take in the 5th and 7th grades, as well as rating on a Childhood Behavioral Checklist that is administered to parents, teachers, and the students themselves. We will test the hypothesis that accumulated lead burden is a major risk factor for poor cognitive and behavioral outcomes, outcomes that have been noted to be highly prevalent in this community. In a parallel effort, we will survey indigenous vegetation on the Tar Creek Superfund Site to determine plant species diversity and spatial distribution with accompanying measurements of lead in plant tissue and soil. Our analysis will determine if patterns of indigenous vegetation predict phytoremediation processes (interaction of plants and soil lead contaminants). We will incorporate this data and collect new data on hydrogeologic, horticultural, and climatic factors to design a community- based model phytoremediation plan. We will test the hypothesis that phytoremediation can reduce high soil lead concentrations in targeted areas. Finally, we will use the bone and blood lead level data generated from epidemiologic study to target exposure assessment follow-up studies of individuals with high and low lead burdens who live in close proximity to "chat" piles, and examine spatial, ecological, home, and behavioral factors that predict whether a child develops high or low lead burdens when living in a highly contaminated environment.