Air Quality in the Maracanã and Deodoro Zones During the Rio 2016 Olympic Games

The air quality during the Summer 2016 Olympic Games in two Olympic zones, Maracanã (Tijuca) and Deodoro, was studied. Volatile organic compounds (VOCs) were collected and analyzed following method TO-15 (United States Environmental Protection Agency), during and in the days after the Games. The total VOC (C4-C12) concentrations were 39.2-160.9 and 36.6-191.4 µg m-3 for Tijuca and Deodoro, respectively. These concentrations were lower than values previously obtained in Tijuca and other areas of the city. VOC speciation and benzene/toluene ratios were also different as a consequence of the restrictions imposed on vehicular transit during the Olympic Games. Concentrations were discussed considering the reactivity and ozone forming potential of individual compounds. Criteria pollutants, determined by the Tijuca Automatic Monitoring Station, were also analyzed. The preventive policies were successful in decreasing the concentrations of CO and PM10, leading to a decrease in mean ozone levels. However, air quality indexes were not dramatically reduced, because of the increase in NOx emissions and isolated events of higher ozone levels.

本研究针对2016年夏季奥运会期间两个奥运赛区——马拉卡纳（蒂茹卡）与德奥多罗的空气质量展开了调研。研究在奥运会举办期间及赛后数日，按照美国环境保护署制定的TO-15方法采集并分析了挥发性有机物（Volatile Organic Compounds, VOCs）。蒂茹卡与德奥多罗的总挥发性有机物（C4-C12）浓度范围分别为39.2~160.9 μg·m⁻³与36.6~191.4 μg·m⁻³。上述浓度均低于此前在蒂茹卡及该市其他区域测得的数值。受奥运会期间车辆通行管制措施影响，VOC组分特征与苯/甲苯比值也出现了差异。研究结合各单体化合物的反应活性与臭氧生成潜势，对污染物浓度展开了讨论。本研究同时分析了蒂茹卡自动监测站测定的环境空气质量标准管控污染物。本次奥运期间实施的预防性管控政策有效降低了一氧化碳（CO）与PM10的浓度，进而使臭氧平均水平有所下降。但由于氮氧化物（NOₓ）排放量上升，以及偶发的高臭氧浓度事件，空气质量指数并未出现显著改善。