Project 3: Consequences of As & Mn Exposure on Childhood Intelligence

在过去的赠款周期中，在孟加拉国的Araihazar工作，那里有广泛的 砷（As）和锰（Mn）在饮用水中，我们已经证明，这两种元素有不利的， 对儿童智力的影响。本提案旨在进一步检验和阐述以下假设， 在两个不同的人群样本中，砷和锰暴露与智力功能缺陷有关。 第一个是美国人口，我们能够应用标准化分数来估计 与IQ的关联程度。第二个项目利用孟加拉国人口来研究是否或 砷对智力功能的影响不是可逆的;它利用了哥伦比亚地球研究所的一个优势， 在孟加拉国Araihazar，向受影响的人口提供无砷深管井水的倡议。 在新罕布什尔州，我们将对500名四年级儿童进行一项横断面研究， 水体As、Mn与IQ的关系。我们选择了一些学校， 根据美国地质勘探局的数据，70%的人将从砷浓度< 10微克/升的威尔斯井中取水，30%的人将从砷浓度>10微克/升的威尔斯井中取水。 锰在威尔斯井中的分布特征不太清楚，但有限的美国地质勘探局数据表明，大约10%的 该区域的威尔斯井的锰浓度将高于300 ug/L的EPA健康建议水平。 在孟加拉国，我们将检验这一假设，即低砷/低锰威尔斯的供应与以下因素有关： 改善智力功能。我们建议对300名儿童（基线年龄7-9岁）进行为期两年的前瞻性研究 在孟加拉国的Araihazar。对于以下4组中的每一组，将招募75名儿童： Mn; B）低As，高Mn; c）高As，低Mn; d）高As，高Mn。根据EPA指南， “低砷”<10微克/升，“低锰”< 300微克/升。 将为高As威尔斯井提供低As/低Mn社区威尔斯井和教育，以促进他们的 使用.儿童将在补救前和补救后12个月和24个月进行评估。 鉴于在美国，约有130万人暴露于饮用水中> 10微克/升的砷， 和家庭锰，虽然不太好地表征，已知是在几个州（如PA，NH）， 确定对儿童智力不利影响可能对公共卫生和 以及制定减少接触的政策。

During the past grant cycle, working in Araihazar, Bangladesh, where there is a wide range of both arsenic (As) and manganese (Mn) in drinking water, we have demonstrated that both elements have adverse effects on child intelligence. The current proposal seeks to further test and elaborate on the hypotheses that exposure to As and Mn are associated with deficits in intellectual function in two distinct population samples. The first draws on a U.S. population, for whom we are able to apply standardized scores to estimate the magnitude of the association with IQ. The second draws on a Bangladesh population to examine whether or not the effects of As on intellectual function are reversible; it takes advantage of a Columbia Earth Institute initiative to provide As-free deep tube-well water to an exposed population in Araihazar, Bangladesh. In New Hampshire (NH), we will conduct a cross-sectional study of 500 fourth-grade children to examine the relations between water As, water Mn and IQ. We selected schools to yield a sample in which roughly 70% will consume water from wells with < 10 ug As/L, 30% from wells with >10 ug/L, based on USGS data. The distribution of Mn in wells is less well characterized, but limited USGS data indicates that roughly 10% of wells in this region will have Mn concentrations above the EPA Health Advisory Level of 300 ug/L. In Bangladesh, we will test the hypothesis that provision of low As/low Mn tube wells is associated with improved intellectual function. We propose a two-year prospective study of 300 children (baseline ages 7-9) in Araihazar, Bangladesh. For each of the following 4 groups, 75 children will be recruited: a) low As, low Mn; b) low As, high Mn; c) high As, low Mn; d) high As, high Mn. Based on EPA guidelines, the definition of "low As" will be < 10ug/L, and "low Mn" will be < 300 ug/L After their initial intellectual assessment, children with high As wells will be provided access to low As/low Mn community wells and education to promote their use. Children will be assessed before remediation and at 12- and 24-months post-remediation. Given that in the U.S., approximately 1.3 million people are exposed to > 10 ug/L As in drinking water, and household Mn, though less well characterized, is known to be elevated in several states (e.g. PA, NH), identification of adverse effects on childhood intelligence may have significant impact both on public health and on establishment of policies to reduce exposure.