Comparative Assessment of the Impact of COVID-19 Lockdown on Air Quality: A Multinational Study of SARS-CoV-2 Hotspots

Comparative Assessment of the Impact of COVID-19 Lockdown on Air Quality: A Multinational Study of SARS-CoV-2 Hotspots | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comparative Assessment of the Impact of COVID-19 Lockdown on Air Quality: A Multinational Study of SARS-CoV-2 Hotspots Ahmed Ould Boudia, Mohamed Asheesh, Frank Adusei-Mensah, Yazid Bounab This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3881962/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract In response to the global COVID-19 pandemic, nations implemented lockdown measures to contain the virus. This study assessed air pollution levels during and after lockdowns, focusing on heavily affected locations: Oulu and Helsinki in Finland, Paris in France, Madrid in Spain, Milan in Italy, and Wuhan in China. Air Quality Index (AQI) data from these areas over two years were analyzed to understand lockdown effects. COVID-19 lockdowns in six cities were compared with SARS-CoV-2 measures using statistical methods. Pollutant Outdoor variations were evaluated via tests, showing significant differences. Parametric analyses and regression studied lockdown impacts on pollution and relationships. The study comprehensively analyzed COVID-19 lockdowns' effects on air quality, identifying differences, quantifying changes, and exploring patterns in Oulu and Helsinki. Pollutant correlations varied among cities during lockdowns. Regression analysis highlighted independent variables' impact on pollutants. Decreases in NO 2 were seen in Helsinki, Madrid, Oulu, Paris, and Milan, reflecting reduced traffic and industry. PM 2.5 and PM 10 reductions occurred in these cities and also Wuhan, except for O 3 levels which increased. Reduced human activities improved air quality, especially for NO 2 and PM 10 . Regional variations necessitate tailored interventions. We observed that during the COVID-19 lockdowns, there was a substantial decrease in both PM 2.5 and NO 2 levels, indicating a direct correlation between reduced human activities, such as transportation and industrial operations, and improved air quality. This underscores the potential impact of environmental measures and suggests the need for sustainable practices to mitigate urban pollution. Environmental Engineering Environmental Policy Atmospheric Sciences Lockdown Air Pollution Air Quality Pandemic-related lockdown measures COVID-19 pandemic reduction environmental interventions Full Text Additional Declarations The authors declare no competing interests. Supplementary Files Table.docx Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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This study assessed air pollution levels during and after lockdowns, focusing on heavily affected locations: Oulu and Helsinki in Finland, Paris in France, Madrid in Spain, Milan in Italy, and Wuhan in China. Air Quality Index (AQI) data from these areas over two years were analyzed to understand lockdown effects. COVID-19 lockdowns in six cities were compared with SARS-CoV-2 measures using statistical methods. Pollutant Outdoor variations were evaluated via tests, showing significant differences. Parametric analyses and regression studied lockdown impacts on pollution and relationships. The study comprehensively analyzed COVID-19 lockdowns' effects on air quality, identifying differences, quantifying changes, and exploring patterns in Oulu and Helsinki. Pollutant correlations varied among cities during lockdowns. Regression analysis highlighted independent variables' impact on pollutants. Decreases in NO\u003csub\u003e2\u003c/sub\u003e were seen in Helsinki, Madrid, Oulu, Paris, and Milan, reflecting reduced traffic and industry. PM\u003csub\u003e2.5\u003c/sub\u003e and PM\u003csub\u003e10\u003c/sub\u003e reductions occurred in these cities and also Wuhan, except for O\u003csub\u003e3\u003c/sub\u003e levels which increased. Reduced human activities improved air quality, especially for NO\u003csub\u003e2\u003c/sub\u003e and PM\u003csub\u003e10\u003c/sub\u003e. Regional variations necessitate tailored interventions. We observed that during the COVID-19 lockdowns, there was a substantial decrease in both PM\u003csub\u003e2.5\u003c/sub\u003e and NO\u003csub\u003e2\u003c/sub\u003e levels, indicating a direct correlation between reduced human activities, such as transportation and industrial operations, and improved air quality. 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