Influence of the COVID-19 pandemic on nitrogen dioxide pollution in the city of Oran, Algeria

Introduction and objectives: The COVID-19 pandemic has had a significant impact on air pollution around the world. Indeed, the concentration of major air pollutants decreased due to lower activities consuming fossil and and polluting fuels. Among these pollutants, nitrogen dioxide (NO2) is a major indicator of air quality. We observed the same phenomenon in the city of Oran in Algeria, which experienced, during the months of April and May 2020, strict containment to limit the spread of COVID-19. The objective of this work is to assess the evolution of NO2 pollution in the city of Oran during and after confinement during two measurement campaigns. Methods: The level of NO2 pollution was measured during these 2 campaigns, using the APOMOS system (Air Pollution Monitoring System) that we developed. This electronic assembly is equipped with the MICS-6814 electrochemical sensor as well as a GPS module (Global positioning system) allowing the geolocation of measurement points. Results: The Geographic Information System (GIS) that we have also developed has facilitated the analysis and mapping of results which show a downward trend in NO2 pollution during confinement in Oran. Conclusion: This study confirms the impact of road traffic on NO2 pollution, especially in the downtown of Oran city.