Moutinho Jennifer L, Liang Donghai, Golan Rachel, Sarnat Stefanie E, Weber Rodney, Sarnat Jeremy A, Russell Armistead G
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, USA.
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, USA.
Atmos Environ (1994). 2020 Mar 1;224. doi: 10.1016/j.atmosenv.2020.117318. Epub 2020 Jan 31.
Exposure to vehicular emissions has been linked to numerous adverse health effects. In response to the arising concerns, near-road monitoring is conducted to better characterize the impact of mobile source emissions on air quality and exposure in the near-road environment. An intensive measurement campaign measured traffic-related air pollutants (TRAPs) and related data (e.g., meteorology, traffic, regional air pollutant levels) in Atlanta, along one of the busiest highway corridors in the US. Given the complexity of the near-road environment, the study aimed to compare two near-road monitors, located in close proximity to each other, to assess how observed similarities and differences between measurements at these two sites inform the siting of other near-road monitoring stations. TRAP measurements, including carbon monoxide (CO) and nitrogen dioxide (NO), are analyzed at two roadside monitors in Atlanta, GA located within 325m of each other. Both meteorological and traffic conditions were monitored to assess the temporal impact of these factors on traffic-related pollutant concentrations. The meteorological factors drove the diurnal variability of primary pollutant concentration more than traffic count. In spite of their proximity, while the CO and NO concentrations were correlated with similar diurnal variations, pollutant concentrations at the two closely sited monitors differed, likely due to the differences in the siting characteristics reducing the dispersion of the primary emissions out of the near-road environment. Overall, the near-road TRAP concentrations at all sites were not as elevated as seen in prior studies, supporting that decreased vehicle emissions have led to significant reductions in TRAP levels, even along major interstates. Further, the differences in the observed levels show that use of single near-road observations will not capture pollutant levels representative of the local near-road environment and that additional approaches (e.g., air quality models) are needed to characterize exposures.
接触车辆排放物已被证明与众多不良健康影响有关。针对这些日益引起关注的问题，开展了近路监测，以更好地描述移动源排放物对近路环境空气质量和暴露情况的影响。在美国最繁忙的公路走廊之一沿线的亚特兰大，进行了一次密集测量活动，测量了与交通相关的空气污染物（TRAPs）及相关数据（如气象、交通、区域空气污染物水平）。鉴于近路环境的复杂性，该研究旨在比较两个彼此相邻的近路监测器，以评估这两个站点测量结果之间观察到的异同如何为其他近路监测站的选址提供信息。在佐治亚州亚特兰大的两个相距325米以内的路边监测器上，对包括一氧化碳（CO）和二氧化氮（NO）在内的TRAP测量数据进行了分析。同时监测了气象和交通状况，以评估这些因素对与交通相关污染物浓度的时间影响。气象因素对一次污染物浓度的日变化影响大于交通流量。尽管两个监测器位置相近，但CO和NO浓度虽具有相似的日变化相关性，但两个紧邻监测器处的污染物浓度仍存在差异，这可能是由于选址特征的差异减少了一次排放物在近路环境中的扩散。总体而言，所有站点的近路TRAP浓度并不像先前研究中那么高，这表明车辆排放的减少已导致TRAP水平显著降低，即使是在主要州际公路沿线。此外，观察到的水平差异表明，仅使用单个近路观测结果无法获取代表当地近路环境的污染物水平，需要采用其他方法（如空气质量模型）来描述暴露情况。
