The Commuter Exposure Study: Linking Exposure, Source-Receptor Models, and Health

描述(由申请人提供)：机动车排放一种复杂的有毒化学物质混合物，这在很大程度上增加了该国空气污染暴露的负担。虽然已经证明环境空气污染和心肺影响之间存在一致的联系，但关于交通相关空气污染的暴露和健康影响，特别是在通勤期间，人们知之甚少。即使在背景空气污染水平较低的社区，通勤期间也存在强烈的短期暴露，这可能会对健康造成不利影响。在以前的空气污染研究中，健康的运动人群(如骑自行车的人)被忽视了。这类活动会增加肺部剂量的人群在通勤者中是一个潜在的弱势群体。因此，有必要提高我们对交通相关空气污染的来源、暴露和健康影响之间的相互作用的理解。这项研究的目的是应用创新的建模和暴露评估及建模技术，以提高我们对与交通相关的空气污染对人类暴露和健康的影响的理解。为了实现这一目标，我们提出了以下具体目标：(1)对不同交通方式(汽车、自行车)和路线(高流量和低流量)的通勤者个人暴露于与交通相关的空气污染进行为期两年的研究；(2)开发和评估一个暴露建模系统，该系统集成了空气污染的机械性命运和运输建模、路径跟踪暴露估计和贝叶斯更新；以及(3)评估早晨通勤期间个人暴露水平与亚临床呼吸和心血管反应的短期关联，这些反应是将空气污染与心血管事件联系起来的假想生物途径的核心。我们假设，对于骑自行车的人(与汽车司机相比)和在高流量路线(与低流量路线相比)，个人暴露在与交通相关的空气污染中的风险将显著更高，并且我们的模型系统将成功预测不同路线/方式组合的通勤者的平均累积暴露。我们还假设，在通勤期间个人暴露在与交通相关的空气污染中的增加将与心血管和呼吸反应的急剧增加(从通勤前到通勤后)相关。该项目解决了影响大多数美国人口的空气污染源的暴露和相关健康影响方面的知识空白。鉴于越来越多的证据表明与交通有关的空气污染的不利影响，从这项研究中获得的信息可以使公民能够减少他们每天接触与交通有关的空气污染。日常通勤，无论是骑自行车、机动车还是其他方式，几乎是所有美国人都有的经历。尽管环境空气污染通常被认为是一种无处不在的、非自愿的危害，但开发新知识以减少通勤期间暴露于与交通相关的空气污染的研究可能会对公众健康产生重大影响。

DESCRIPTION (provided by applicant): Motor vehicles emit a complex mixture of toxic chemicals that contributes substantially to the burden of air pollution exposure in this country. While a consistent link between ambient air pollution and cardiopulmonary effects has been demonstrated, very little knowledge exists regarding exposures and health effects of traffic- related air pollution specifically during the commute. Even in communities with low background levels of air pollution, there are intense, short-term exposures during commutes that may contribute to adverse health effects. Healthy, exercising populations (such as cyclists) have been neglected in previous air pollution research. Such populations with activities that increase lung dose are a potentially vulnerable subgroup among commuters. Therefore, a need exists to improve our understanding of the interactions between sources, exposures, and health effects of traffic-related air pollution. The objective of this research is to apply innovative modeling and exposure assessment and modeling techniques to improve our understanding of the impact of traffic-related air pollution on human exposure and health. To achieve this objective we propose the following specific aims: (1) Conduct a two-year study of commuters' personal exposures to traffic-related air pollution among different modes (car, bike) and routes (high- and low-traffic); (2) Develop and evaluate an exposure modeling system that integrates mechanistic air pollution fate and transport modeling, path-following exposure estimation, and Bayesian updating; and (3) Evaluate the short-term association of personal exposure levels during morning commutes with subclinical respiratory and cardiovascular responses that are central to the hypothesized biologic pathway linking air pollution with cardiovascular events. We hypothesize that personal exposures to traffic-related air pollution will be significantly higher for cyclists (vs. car drivers) and on high-traffic routes (vs. low-traffic), and that our model system will successfully predict average cumulative exposures for commuters traveling different route/mode combinations. We also hypothesize that increased personal exposure to traffic-related air pollution experienced during a commute will be associated with acute increases (from pre- to post-commute) in cardiovascular and respiratory responses. This project addresses knowledge gaps on the exposures and related health effects of a source of air pollution that affects the majority of the U.S. population. Given the emerging evidence on the adverse effects of traffic- related air pollution, information gained from this study can empower citizens to reduce their daily exposures to traffic-related air pollution. The daily commute, whether by bicycle, motor vehicle, or other mode, is an experience shared by nearly all Americans. Although ambient air pollution is generally considered a ubiquitous, involuntary hazard, research that develops new knowledge to reduce exposures to traffic-related air pollution during commuting has the potential to produce a substantial public health impact.