交通相关空气污染暴露评估方法研究进展

Research progress on methods to estimate health effects of traffic-related air pollution exposure

本文总结了在评估交通相关空气污染(traffic-related air pollution,TRAP)健康效应研究中定量TRAP的主要方法及其优缺点。TRAP暴露评估的研究目前主要集中在外暴露和内暴露两种评估手段。交通外暴露的定量工作主要依赖于交通相关指标(距离道路远近、交通强度等)或基于模型(空气质量扩散模型、土地利用模型、混合个体模型等)对交通相关空气污染物浓度进行预测;前者作为TRAP长期效应的一种可替代指标,能够在较小的空间尺度范围内捕捉交通排放的长期变化,且是考虑了除交通相关空气污染物以外其他环境风险的综合性指标,但往往会忽视受到众多不同交通水平的道路复合影响的住宅及个体,并且无法考虑气象等条件的影响,而后者可以在不建立密集监测网络的前提下较好地描述污染物的时空变异性,但数据质量和精度是限制模型输出精度的主要条件。还有部分研究选取特异性生物标志物作为交通内暴露的替代,如苯巯基尿酸、反式,反式-戊酸、1-羟基芘、微核率。本综述旨在为评估TRAP和不同疾病之间相关性的流行病学研究提供理论依据,深入探寻相关机制问题。

This review summarized the main methods for the quantification of traffic exposure in studies assessing the health impacts of traffic-related air pollution(TRAP). External and internal exposure assessments are two main approaches to estimate TRAP exposure. In most studies, the quantitative estimation of TRAP external exposure mainly depends on traffic-related metrics(e.g. distance to roads, traffic density) and the prediction of TRAP concentrations based on various models(e.g. air dispersion model, land use regression model, hybrid individual-exposure model). The former is considered as a set of alternative indicators for the long-term effect of TRAP, which can capture long-term changes in traffic emissions at a small spatial scale, and focuses on comprehensive indicators of environmental risks other than traffic-related air pollutants. But it always ignores individuals who are affected by the combined effects of many roads with different traffic levels, and fails to take the effects of conditions such as weather into account. While the latter can better describe the spatiotemporal variability of pollutants without the establishment of intensive monitoring network, but the data quality and accuracy are the main constraints to the accuracy of the models. Additionally, researchers have tried to explore some specific biomarkers to be the proxy of TRAP exposure, such as S-phenylmercapturic acid, trans, trans-muconic acid, 1-hydroxypyrene, and micronucleus frequency. The review was expected to provide a theoretical basis for epidemiological studies to evaluate the correlations between TRAP exposure and different diseases in human, and to give a deeper insight into the related mechanisms.