Air quality during COVID-19 lockdown: Blessing in disguise

Abstract

The world at present is facing a gravest health crisis due to the COVID-19 pandemic. To control its unimaginable transmission worldwide lockdown was implemented resulting in economic deterioration but on the other hand betterment of the environment took place. Therefore this study attempted to analyze the quality of air during the lockdown period and infer its outcome to environment and health. 15 empirical research articles, eight (54%), three (20%), two (13%) and two (13%) from Asia, Europe, South America and North America, respectively have been evaluated. From the studies it was inferred that during the lockdown period, in general, there was a trend of decrease in the level of concentrations of PM10, PM2.5, CO, NO, NO2, NH3, NOx, SO2 and increase in the concentration level of O3 in comparison to either the pre-lockdown period or to the previous year(s) records. Marked decrease in the levels of NO, NO2, NOx were noted. Also PM10, PM2.5, SO2 and CO levels were seen to diminish significantly. The main reasons for such decrease were restricted movements of traffic and temporary closure of factories and industries. However, as the thermal power plants were functional during lockdown so improvement of air quality in those areas was not significant. Overall, significant improvement in the air quality was observed during the lockdown which led to better climatic conditions, lesser pollution and improved many seasonal ailments like asthma and other cardio-respiratory issues in people.