ABSTRACT

The current study evaluated ozone levels through passive samplers installed in 4 different points in a medium-sized city (Rio Grande, Brazil) with naturally low NO₂ levels during a week of COVID-19 lockdown. Additionally, we evaluated the consequences of this response with regard to human health risk assessment and reduction of hospital admissions and ozone-related deaths. The reduction in ozone levels, one month after the implementation of containment measures, varied between 26 and 64% (average of 44%), in the different studied sites. The reduction of human mobility during the pandemic reduced the levels of ozone in Rio Grande city and consequently will bring benefits to health services in the municipality. This unexpected reduction in O₃ levels must be related to the low ‘natural’ levels of NO₂ in the city, which make the contribution of other precursors important for the fluctuation of O₃ levels.

摘要

目前的研究通过安装在一个中等城市（巴西里奥格兰德）的 4 个不同点的被动采样器评估臭氧水平，在 COVID-19 封锁的一周内， NO _{2水平自然较低。}此外，我们评估了这种响应在人类健康风险评估以及减少住院和臭氧相关死亡方面的后果。在实施控制措施一个月后，不同研究地点的臭氧水平降低了 26% 到 64%（平均为 44%）。大流行期间人员流动性的减少降低了里奥格兰德市的臭氧水平，因此将为该市的卫生服务带来好处。_{O 3}的这种意外减少水平必须与城市中 NO ₂的低“自然”水平有关，这使得其他前体的贡献对 O ₃水平的波动很重要。