The legacy lead deposition in soils and its impact on cognitive function in preschool-aged children in the United States
The legacy lead deposition in soils and its impact on cognitive function in preschool-aged children in the United States
复制标题
DOI：
10.1016/j.ehb.2019.03.001
复制
发表时间：
2019-05-01
影响因子：
2.5
通讯作者：
Severnini, Edson
中科院分区：
文献类型：
--
作者：
Clay, Karen;Portnykh, Margarita;Severnini, Edson
长期以来，地表土壤污染一直被认为是人类铅暴露的重要途径，现在是一个全球性的健康问题。这项研究估计了5岁儿童接触表层土壤中的铅对认知能力的因果影响。我们利用2000年美国人口普查的个人水平数据，以及美国地质勘探局关于美国各地各县表土铅含量的数据。使用工具变量的方法依赖于1944年的州际公路系统计划，我们发现，较高的铅在表土大大增加的概率5岁的男孩经历认知困难，如学习，记忆，集中，或决策。生活在表层土铅浓度高于全国中位数的县，5岁男孩有认知困难的概率大约是原来的两倍。然而，它似乎并不影响5岁的女孩，与以前的研究一致。重要的是，即使在美国环保署和州机构的指导方针认为表层土壤铅浓度较低的县，也发现了铅暴露对男孩的不利影响。这些发现令人担忧，因为它们表明，无论是在美国还是在表土中有大量铅沉积的其他国家，遗留的铅可能会继续损害今天的认知能力。(C)2019 Elsevier B.V.版权所有。
Surface soil contamination has been long recognized as an important pathway of human lead exposure, and is now a worldwide health concern. This study estimates the causal effects of exposure to lead in topsoil on cognitive ability among 5-year-old children. We draw on individual level data from the 2000 U.S. Census, and USGS data on lead in topsoil covering a broad set of counties across the United States. Using an instrumental variable approach relying on the 1944 Interstate Highway System Plan, we find that higher lead in topsoil increases considerably the probability of 5-year-old boys experiencing cognitive difficulties such as learning, remembering, concentrating, or making decisions. Living in counties with topsoil lead concentration above the national median roughly doubles the probability of 5-year-old boys having cognitive difficulties. Nevertheless, it does not seem to affect 5-year-old girls, consistent with previous studies. Importantly, the adverse effects of lead exposure on boys are found even in counties with levels of topsoil lead concentration considered low by the guidelines from the U.S. EPA and state agencies. These findings are concerning because they suggest that legacy lead may continue to impair cognition today, both in the United States and in other countries that have considerable lead deposition in topsoil. (C) 2019 Elsevier B.V. All rights reserved.