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. 2021 Jun:197:111052.
doi: 10.1016/j.envres.2021.111052. Epub 2021 Mar 19.

Does air pollution upsurge in megacities after Covid-19 lockdown? A spatial approach

Khurram Shehzad  1 , Liu Xiaoxing  2 , Mahmood Ahmad  3 , Abdul Majeed  4 , Farheen Tariq  5 , Salman Wahab  6
Affiliations

Does air pollution upsurge in megacities after Covid-19 lockdown? A spatial approach

Khurram Shehzad et al. Environ Res. 2021 Jun.

Erratum in

Abstract

The current coronavirus (COVID-19) pandemic has a high spreading and fatality rate. To control the rapid spreading of the COVID-19 virus, the government of India imposed lockdown policies, which creates a unique opportunity to analyze the impact of lockdown on air quality in the two most populous cities of India, i.e., Delhi and Mumbai. To do this, the study employed a spatial approach to examine the concentration of seven criteria pollutants, i.e., PM2.5, PM10, NH3, CO, NO2, O3, and SO2, before, during, and after a lockdown in Delhi and Mumbai. Overall, around 42%, 50%, 21%, 37%, 53%, and 41% declines in PM2.5, PM10, NH3, CO, NO2, and SO2 were observed during the lockdown period as compared to previous years. On the other hand, a 2% increase in O3 concentration was observed. However, the study analyzed the National Air Quality Index (NAQI) for Delhi and Mumbai and found that lockdown does not improve the air quality in the long term period. Our key findings provide essential information to the cities' administration to develop rules and regulations to enhance air quality.

Keywords: Air quality; COVID-19; India; Lockdown; Spatial analysis.

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Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Fig. 1
Fig. 1
Spatial investigation of PM2.5, PM10, CO, and NO2 in NCT Delhi and Mumbai.
Fig. 1
Fig. 1
Spatial investigation of PM2.5, PM10, CO, and NO2 in NCT Delhi and Mumbai.
Fig. 1
Fig. 1
Spatial investigation of PM2.5, PM10, CO, and NO2 in NCT Delhi and Mumbai.
Fig. 1
Fig. 1
Spatial investigation of PM2.5, PM10, CO, and NO2 in NCT Delhi and Mumbai.
Fig. 2
Fig. 2
Spatial investigation of SO2, NH3, and O3, in Delhi and Mumbai.
Fig. 2
Fig. 2
Spatial investigation of SO2, NH3, and O3, in Delhi and Mumbai.
Fig. 2
Fig. 2
Spatial investigation of SO2, NH3, and O3, in Delhi and Mumbai.
Fig. 3
Fig. 3
Variations in PM2.5, PM10, CO, O3, NO2, SO2, and NH3 in Delhi.
Fig. 3
Fig. 3
Variations in PM2.5, PM10, CO, O3, NO2, SO2, and NH3 in Delhi.
Fig. 4
Fig. 4
Variations in PM2.5, PM10, CO, O3, NO2, SO2, and NH3 in Mumbai.
Fig. 4
Fig. 4
Variations in PM2.5, PM10, CO, O3, NO2, SO2, and NH3 in Mumbai.
Fig. 5
Fig. 5
National air quality index (NAQI) for Delhi and Mumbai.
See this image and copyright information in PMC

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References

    1. Baldasano J.M. COVID-19 lockdown effects on air quality by NO2 in the cities of Barcelona and Madrid (Spain) Sci. Total Environ. 2020;741:140353. doi: 10.1016/j.scitotenv.2020.140353. - DOI - PubMed
    1. Bao R., Zhang A. Does lockdown reduce air pollution? Evidence from 44 cities in northern China. Sci. Total Environ. 2020;731:139052. doi: 10.1016/j.scitotenv.2020.139052. - DOI - PMC - PubMed
    1. Beig G., Ghude S.D., Deshpande A. Indian Institute of Tropical Meteorology; 2010. Scientific Evaluation of Air Quality Standards and Defining Air Quality Index for India.https://www.tropmet.res.in/~lip/Publication/RR-pdf/RR-127.pdf
    1. Bherwani H., Nair M., Musugu K., Gautam S., Gupta A., Kapley A., Kumar R. Valuation of air pollution externalities: comparative assessment of economic damage and emission reduction under COVID-19 lockdown. Air Qual. Atmos. Heal. 2020;13:683–694. doi: 10.1007/s11869-020-00845-3. - DOI - PMC - PubMed
    1. Blondet I., Schreck E., Viers J., Casas S., Jubany I., Bahí N., Zouiten C., Dufréchou G., Freydier R., Galy-Lacaux C., Martínez-Martínez S., Faz A., Soriano-Disla M., Acosta J.A., Darrozes J. Atmospheric dust characterisation in the mining district of Cartagena-La Unión, Spain: air quality and health risks assessment. Sci. Total Environ. 2019;693:133496. doi: 10.1016/j.scitotenv.2019.07.302. - DOI - PubMed

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