São Paulo’s atmospheric pollution reduction and its social isolation effect, Brazil

Abstract

Since January 2020, studies report reductions in air pollution among several countries due to social isolation measures, which have been adopted in order to contain the coronavirus outbreak progress (COVID-19). This study aims to evaluate the change in the atmospheric pollution levels by NO and NO 2 in São Paulo City for the social isolation period. The NO and NO 2 hourly concentrations were obtained through air quality monitoring stations from CETESB, from January 14, 2020 to April 12, 2020. Mann-Kendall and the Pettitt tests were performed in the air pollutant time series. We observed an overall negative trend in all stations, indicating a decreasing temporal pattern in concentrations. Regarding NO, the highest absolute decrease rates were observed in the Congonhas (− 6.39 μg m −3 month −1 ) and Marginal Tietê (− 6.19 μg m −3 month −1 ) stations; regarding NO 2 , the highest rates were observed in the Marginal Tietê (− 4.45 μg m −3 month −1 ) and Cerqueira César (− 4.34 μg m −3 month −1 ) stations. In addition, we identified a turning point in the NO and NO 2 series trends that occurred close to the start date of the social isolation period (March 20, 2020). Moreover, from statistical analysis, it was found that NO 2 is a suitable surrogate for monitoring economic activities during social isolation periods. Thus, we concluded that social isolation measures implemented on March 20, 2020 caused significant changes in the air pollutant concentrations in the city of São Paulo (as high as − 200% in NO 2 levels).

The relationship between the number of COVID-19 cases, meteorological variables, and particulate matter concentration in a medium-sized Brazilian city

“…Several social distancing measures have been adopted worldwide in an attempt to contain the advance of the COVID-19 outbreak, and, in general, had a direct impact on anthropogenic activities, such as decreased vehicular traffic and reduced industrial activities (Chen et al, 2020;Selvam et al, 2020;Rosse et al, 2021), changing the atmospheric emissions and improving the air quality in several countries (Chauhan and Singh, 2020), such as Spain (Tobías et al, 2020), China (Chu et al, 2021) and India (Singh and Chauhan, 2020).…”

“…In Latin America, some studies have also been carried out, such as in Ecuador (Zambrano-Monserrate and Ruano, 2020) and Brazil (Dantas et al, 2020;Nakada and Urban, 2020;Rosse et al, 2021;Rudke et al, 2021). In a way, the measures adopted during the pandemic provided an opportunity to investigate the behavior of air pollutants, such as in situations of lower vehicle traffic (Krecl et al, 2020;Rosse et al, 2021;Rudke et al, 2021).…”