Study of Prevalent Neurotoxicants in Children

描述(由申请人提供) 接触多种环境物质，包括铅、汞、多氯联苯和 环境烟草烟雾与不良神经行为有关 效果。尽管如此，测量宫内暴露的理想生物标志物fF 具体的毒物尚未确定，许多毒物的不良影响 潜在的神经毒物还没有经过严格的测试。胎儿暴露在 通常通过自我报告的调查、母亲的血液和尿液或 脐带血。相比之下，胎粪作为生物标志物是一种非侵入性的方法 同时检测大量毒物的累积暴露情况。但它是 不清楚是常规生物标志物还是胎粪水平更具预测性 与特定毒物有关的不良反应。对于铅暴露， 新出现的数据表明，我们的努力应该强调初级预防， 但铅危害控制的有效性尚不确定，特别是对 血铅浓度低的儿童。调查人员提议 对不到16周的400名儿童进行队列研究 妊娠到36个月，如果年龄，检查低水平暴露的影响 流行的神经毒药。端点包括行为问题，例如 行为障碍和ADHD的特征，认知障碍，和 听力损失。调查人员还将进行嵌套、随机 对照试验，以测试铅危害控制的有效性 不良神经行为影响的发展。他们将测试以下内容 假设：1)降铅组的孩子会有血铅 2.7ug/dL(30%)或更低的水平，显著提高认知力 得分、听力损失更少，行为问题比一个对照组更少 36月龄组。2)胎儿和出生后接触杀虫剂， 内毒素和铅(血液水平低于10ug/dL)与不良反应有关 儿童早期的神经行为影响、生长迟缓和听力损失。 3)通过调查(ETS)、母亲和脐带血测量的胎儿接触情况 (铅、甲基汞、农药和其他物质)和尿液(农药)较少 预测毒物对认知、行为的不良影响 问题和听力，与胎粪中的相同毒物相比。 该项目与项目中描述的研究相结合 2，将测试一项干预措施的有效性，用于初级预防 铅毒性，通过铅浓度和神经行为来衡量 在36个月龄时发挥作用，作为评估不利因素的模型 多种流行毒物对胎儿和胎儿的影响 儿童检测胎粪水平作为胎儿暴露于 毒物，并提供住宅的暴露和风险评估数据 杀虫剂。

DESCRIPTION (provided by applicant) Exposure to numerous environmental agents, including lead, mercury, PCBs, and environmental tobacco smoke, has been linked with adverse neurobehavioral effects. Still, the ideal biomarker fof measuring in utero exposure to specific toxicants has not been established and the adverse effects of many potential neurotoxicants have not been rigorously tested. Fetal exposure is typically measured with self-reported surveys, maternal blood and urine, or cord blood. In contrast, meconium as a biomarker is a non-invasive method to simultaneously test for cumulative exposures to numerous toxicants. But it is unclear whether conventional biomarkers or meconium levels are more predictive of the adverse effects linked with specific toxicants. For lead exposure, emerging data indicate that our efforts should emphasize primary prevention, but the efficacy of lead hazard controls are uncertain, especially for children with low blood lead concentrations. The investigators propose to conduct a cohort study of 400 children, followed from less than 16 weeks gestation to 36 months if age, to examine the effect of low-level exposures to prevalent neurotoxicants. Endpoints include behavioral problems, such as conduct disorder and features consistent with ADHD, cognitive deficits, and hearing loss. The investigators will also conduct a nested, randomized controlled trial to test the efficacy of lead hazard controls on the development of adverse neurobehavioral effects. They will test the following hypotheses: 1) Children in the Lead Reduction Group will have blood lead levels that are 2.7 ug/dL (30%) or lower, significantly higher cognitive scores, less hearing loss, and fewer behavioral problems than one Control group at 36 months of age. 2) Fetal and postnatal exposures to pesticides, ETS and lead (at blood levels below 10 ug/dL) are associated with adverse neurobehavioral effects, growth delay and hearing loss in early childhood. 3) Fetal exposures, as measured by survey (ETS), maternal and cord blood (lead, methyl mercury, pesticides and ETS), and urine (pesticides), are less predictive of the adverse effects of toxicants on cognition, behavioral problems and hearing, compared with the same toxicants in meconium. This project, in combination with the research described in Project 2, will test the efficacy of an intervention for the primary prevention of lead toxicity, as measured by lead concentration and neurobehavioral functioning at 36 months of age, serve as a model to evaluate the adverse effects of exposures to multiple prevalent toxicants among fetuses and children test meconium levels as a biomarker of fetal exposure to numerous toxicants, and provide exposure and risk assessment data for residential pesticides.