Air Pollution and Children's Cognitive and Health Outcomes

描述（由申请人提供）：空气污染仍然是一个严重的公共卫生问题，特别是对于儿童来说，他们比成年人更容易受到环境空气污染的不利影响，因为他们在户外度过的时间更长，户外体育活动的发生率更高，并且仍在发育的生物和免疫系统。大量文献已将暴露于标准污染物（颗粒物、地面臭氧、一氧化碳、硫氧化物、氮氧化物和铅）与儿童的不良健康结果联系起来，然而，这些文献大多基于横断面研究，因此尚不清楚这些关系是否仅仅反映了选择的影响或未观察到的混杂因素。大多数研究都是基于地理上有限的样本，因此限制了普遍性。此外，尽管污染对儿童认知结果的影响研究有限

DESCRIPTION (provided by applicant): Air pollution remains a serious public health concern, particularly for children who are more susceptible to the adverse effects of ambient air pollution relative to adults because of more time spent outdoors, higher incidence of outdoor physical activity, and still developing biological and immune system. A substantial body of literature has linked exposure to criteria pollutants (particulate matter, ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead) with adverse health outcomes in children, however, much of this literature is based on cross-sectional studies and therefore it is not clear whether these relationships merely capture the influence of selection or unobserved confounders. Most studies are based on geographically- limited samples thereby limiting generalizability. In addition, there is limited research on pollution's effects on children's cognitive outcomes despite preliminary evidence identifying a potential biological link. In this study, we propose to use longitudinal data on a nationally representative sample of children in the U.S and quasi-experimental methods to estimate the relationship between ambient air pollution exposure during the elementary and middle school years on children's health and cognitive outcomes. Our study has three specific aims: 1. Describe the short and long-term exposure to ambient air pollution in a nationally representative sample throughout elementary and middle school years and identify individual, family, and contextual factors that predict exposure. 2. Estimate the relationship between ambient air pollution exposure and children's health and cognitive outcomes including respiratory health problems, general health status, cognitive learning disabilities, cognitive development, and school absences. 3. Examine whether the estimated relationships between air pollution and children's outcomes vary with observable child characteristics including gender, race-ethnicity, socioeconomic status, participation in outdoor activities, and health characteristics. The analyses will link individual level data from the Earl Childhood Longitudinal Study - Kindergarten Cohort (ECLS-K) to the Environmental Protection Agency's criteria pollutant data. We will examine children's outcomes from all waves of the panel starting in kindergarten (n=21,260) through 8th grade (n=9,725). Given the complexities of addressing the potential endogeneity of pollution exposure, we will undertake several well- established econometric approaches including propensity score weighting, instrumental variables estimation, and child fixed effects models. Our findings will provide important evidence regarding whether reductions in air pollution are linked to children's health and cognitive outcomes, and consequently whether we can expect future efforts to control pollution to do so.