Special Issue on COVID-19 Aerosol Drivers, Impacts and Mitigation (IV)

Rasa Zalakeviciute  1,2, Renne Vasquez2, Daniel Bayas2, Adrian Buenano2, Danilo Mejia3, Rafael Zegarra3, Valeria Diaz4, Brian Lamb5

1 Grupo de Biodiversidad Medio Ambiente y Salud (BIOMAS), Universidad de Las Americas, Quito – EC 170125, Ecuador
2 Universidad de Las Americas, Quito – EC 170125, Ecuador.
3 Carrera de ingeniería ambiental, Facultad de Ciencias Químicas, Universidad de Cuenca, Cuenca 010203, Ecuador
4 Air Quality Monitoring Network, Secretariat of the Environment, Municipality of the Quito Metropolitan District, Calle Rio Coca, Quito – EC 170125, Ecuador
5 Laboratory for Atmospheric Research, Washington State University, Pullman, WA 99163, USA


Received: May 23, 2020
Revised: June 29, 2020
Accepted: July 5, 2020

 Copyright The Author's institutions. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited. 

Download Citation: ||https://doi.org/10.4209/aaqr.2020.05.0254  

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Cite this article:

Zalakeviciute, R., Vasquez, R., Bayas, D., Buenano, A., Mejia, D., Zegarra, R., Diaz, A. and Lamb, B. (2020). Drastic Improvements in Air Quality in Ecuador during the COVID-19 Outbreak. Aerosol Air Qual. Res. 20: 1783–1792. https://doi.org/10.4209/aaqr.2020.05.0254


  • Impact of reduced human activities on urban air quality in Ecuador is investigated.
  • Air quality in Quito, Ecuador improved by 29–68% due to COVID-19 quarantine measures.
  • Geographic dependent pollution reductions vary due to differing preventative measures.


In the beginning of 2020, the global human population encountered the pandemic of novel coronavirus disease 2019 (COVID-19). Despite social and economic concerns, this epidemiologic emergency has brought unexpected positive consequences for environmental quality as human activities were reduced. In this paper, the impact of restricted human activities on urban air quality in Ecuador is investigated. This country implemented a particularly strict set of quarantine measures at the very dawn of the exponential growth of infections on March 17, 2020. As a result, significant reductions in the concentrations of NO2 (–68%), SO2 (–48%), CO (–38%) and PM2.5 (–29%) were measured in the capital city of Quito during the first month of quarantine. This large drop in air pollution concentrations occurred at all the monitoring sites in Quito, serving as a valuable proof of the anthropogenic impact on urban air quality. The spatial evolution of atmospheric pollution using observed surface and satellite data, showed different results for the two major cities: Quito and Guayaquil. While the population in Quito adhered to the quarantine measures immediately, in the port city of Guayaquil, quarantine measures were slow to be adopted and, thus, the effect on air quality in Guayaquil occurred more slowly. This lag could have a considerable cost to the mortality rate in the port city, not only due to the spread of the disease but also due to the poor air quality. Overall, the air quality data demonstrate how quickly air quality can improve when emissions are reduced.

Keywords: COVID-19; Urban air pollution; Quarantine measures.


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Aerosol Air Qual. Res. 20 :1783 -1792 . https://doi.org/10.4209/aaqr.2020.05.0254  

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