Novel exposure metrics for assessing the effects of ultrafine and fine particulate matter on asthma in children

项目摘要 众所周知，颗粒物(PM)空气污染会加重儿童的哮喘症状；然而，它仍然是 不清楚PM的哪一项指标(颗粒大小、形态或化学成分)与呼吸最相关 健康。这项工作的广泛目标是确定细微PM的哪些潜在的可修改因素， 包括超细颗粒物(UFP)、微环境和峰值暴露，与呼吸道相关 对市中心哮喘儿童的影响。第二个相关目标是评估这些优秀PM的效果 超重儿童哮喘的影响因素，这是我们中心最近确认的一个易感人群。至 为了实现这些目标，我们将在一个由50人组成的小组研究中检查PNC和峰值PM暴露的影响 哮喘儿童，每名儿童将被跟踪7天，并持续监测4天的PNC 以及PM2.5质量、地理位置、生物标志物和哮喘结果。在目标1中，我们将评估 UFP和细颗粒物与哮喘症状、肺功能及炎症的关系 生物标志物。我们将使用位置信息将暴露分配到微环境中 儿童花费时间(例如，家庭、学校、交通工具)并评估它们之间的关系 微环境暴露以及暴露的较长期措施对哮喘结果的影响。在AIM 2 我们将开发一个自动峰值检测算法，并评估峰值曝光对 累积暴露量和估计峰值暴露量对哮喘儿童的影响。最后，在目标3中，我们 将评估体重作为UFP、微环境和峰值影响的易感因素的作用 暴露在哮喘结果上。我们希望这项研究的设计，利用最新的技术 进展，将提供前所未有的能力来评估精细PM因素对哮喘的重要性 对儿童的影响。这样的证据将允许个性化的环境干预战略， 以易感人群为目标。

Project Summary Particulate matter (PM) air pollution is known to exacerbate asthma symptoms in children; however, it is still unclear which metric (particle size, morphology or chemical composition) of PM is most relevant to respiratory health. The broad objective of this work is to determine which potentially modifiable factors of fine PM, including ultrafine particles (UFP), microenvironment, and peak exposure, are associated with respiratory effects in inner-city children with asthma. A second, related objective is to evaluate the effects of these fine PM factors on overweight children with asthma, a susceptible population recently identified by our Center. To accomplish these objectives, we will examine the effects of PNC and peak PM exposure in a panel study of 50 children with asthma, each of whom will be followed for 7 days with 4 days of continuous monitoring of PNC and PM2.5 mass, geographic location, biomarkers, and asthma outcomes. In Aim 1 we will evaluate the relationship between UFP and fine particles and asthma symptoms, lung function and inflammatory biomarkers. We will use the location information to apportion exposure into the microenvironments in which children spend time (e.g. home, school, transit) and evaluate the relationships between these microenvironmental exposures, as well as longer-term measures of exposure, on asthma outcomes. In Aim 2 we will develop an automated peak detection algorithm and evaluate the contribution of peak exposures to cumulative exposure and estimate the effects of peak exposures on children with asthma. Finally, in Aim 3, we will evaluate the role of weight as a susceptibility factor for the impact of UFP, microenvironmental, and peak exposures on asthma outcomes. We expect that this study design, taking advantage of recent technological advancements, will provide unprecedented ability to assess the importance of fine PM factors on asthma outcomes in children. Such evidence will allow for individualized environmental intervention strategies that target susceptible populations.