Impact of SARS-CoV-2 lockdown and de-escalation on air-quality parameters. (February 2021)

• Record Type: Journal Article
• Authors: Viteri, G.; Díaz de Mera, Y.; Rodríguez, A.; Rodríguez, D.; Tajuelo, M.; Escalona, A.; Aranda, A.
• Is Part Of: Chemosphere. Volume 265(2021)
• Publication Date: 2021-02
• Subjects: SARS-CoV-2 -- Covid-19 -- Lockdown -- de-escalation -- Air pollutants -- Ozone; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2020.129027
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: The SARS-CoV-2 health crisis has temporarily forced the lockdown of entire countries. This work reports the short-term effects on air quality of such unprecedented paralysis of industry and transport in different continental cities in Spain, one of the countries most affected by the virus and with the hardest confinement measures. The study takes into account sites with different sizes and diverse emission sources, such as traffic, residential or industrial emissions. This work reports new field measurement data for the studied pandemic period and assesses the air quality parameters within the historic trend of each pollutant and site. Thus, 2013–2020 data series from ground-air quality monitoring networks have been analysed to find out statistically significant changes in atmospheric pollutants during March–June 2020 due to this sudden paralysis of activity. The results show substantial concentration drops of primary pollutants, including NOx, CO, BTX, NMHC and NH3 . Particulate matter changes were smaller due to the existence of other natural sources. During the lockdown the ozone patterns were different for each studied location, depending on the VOCs-NOx ratios, with concentration changes close to those expected from the historical series in each site and not statistically attributable to the health crisis effects. Finally, the gradual de-escalation and progressive increase of traffic density within cities reflects a slow recovery of primary pollutants. The results and conclusions for these cities, with different sizes and population, and specific emission sources, may serve as a behavioural model for other continental sites and help understand future crises. Graphical abstract: Image 1 Highlights: SARS-CoV-2 lockdown and de-escalation's effects on air quality in different size cities in Spain. Significant and fast reduction of NOx, CO, BTXs, NMHC and NH3 have been observed. Lower changes in PM were found during the crisis and not clear trends for O3. Pollutant levels remained below pre-lockdown values despite gradual de-escalation.