Ozone (O) pollution is a global concern. The real-time ultraviolet (UV) photometric method is commonly employed at the majority of O regulatory monitoring stations around the world. High concentrations of volatile organic compounds (VOCs) have been confirmed to interfere with the real-time O monitoring by this method. However, it is unknown whether VOCs emission in the urban environment has an impact on the O regulatory monitoring. Here we revealed that high VOCs concentration in an urban industrial zone may result in positive artifacts in O measurement at a nearby atmospheric monitoring station. These VOCs were dominated by styrene with concentrations at a mg/m level, which was closely related to the abnormally higher O measurements observed in this station at night. Experimental validation confirmed that benzene homologues could induce evidently O measurement artifacts by the regulatory UV photometric method. By equipped with a temperature control system for the O measurement scrubber to desorb VOCs adsorbed by O the scrubbing catalyst, the O measurement artifacts showed an effective decline with a maximum of 30 ppb in the field cases. This study shed light on the improvement of the air quality assessment by coordination of the monitoring stations and approaches in the future.

中文翻译：

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挥发性有机化合物（VOC）排放干扰城市大气中臭氧的实时监管监测

臭氧（O）污染是全球关注的问题。全球大多数 O2 监管监测站普遍采用实时紫外线 (UV) 光度测定方法。已证实高浓度的挥发性有机化合物 (VOC) 会干扰该方法的实时 O 监测。但城市环境中VOCs排放是否对O监管监测产生影响尚不清楚。在这里，我们发现城市工业区的高 VOC 浓度可能会导致附近大气监测站的 O 测量出现正伪影。这些挥发性有机化合物以苯乙烯为主，浓度为毫克/立方米水平，这与该站夜间观测到的异常较高的氧气测量值密切相关。实验验证证实，苯同系物可以通过监管紫外光度法明显诱导 O 测量伪影。通过为 O 测量洗涤器配备温度控制系统，以解吸 O 洗涤催化剂吸附的 VOC，在现场案例中，O 测量伪影显示出有效下降，最大可达 30 ppb。这项研究为未来通过协调监测站和方法来改进空气质量评估提供了线索。