7 COVID-19: Disaster or an Opportunity …
175
restricting economic activities and personal mobility during COVID-19 improved the
air quality remarkably and brought down the PM 2.5 concentration by 25% which is
capable of averting premature deaths due to air pollution [28]. Marlier et al. (2020)
in their study quantified the changes in the concentration of air pollution in China for
the month January and February of 2019 and 2020. There was a reduction of 48% in
PM 2.5 concentrations, 11% in sulphur dioxide and 49% in nitrogen dioxide during a
3 week period after the Lunar New Year (LNY) in 2020 compared to 2019 which was
mainly due to measures taken for quarantine and decrease in transportation, industrial
pollution and economic activity during COVID-19 [42]. Cadotte (2020) compared
air quality of February 2019 and 2020 in six cities Shanghai, Wuhan, Milan, Hong
Kong, Seoul and Kyoto where restrictions were imposed due to COVID-19 and found
decline in major air pollutants indicating that air quality can be improved through
change in policy by the government [6]. Almond et al. (2020) in their study concluded
that COVID-19 had indefinite impacts on pollution in China. The improvement in
air quality was much less than that expected near the epicentre of the pandemic,
i.e. province of Hubei but the concentration of ozone increased in both absolute and
relative terms [1]. Kuzemko et al. (2020) found that the emission level recorded in
April, 2020 was as low as 10 years ago with Carbon dioxide emissions showing
reduction of 17% in April 2020 as compared to April 2019, due to reduction in
transport [36]. Connerton et al. (2020) studied the air pollution effects caused due
to social distancing and quarantine policies in four megacities: Paris in France, New
York and Los Angeles in the United States, Sao Paulo in Brazil by analysing the
levels of air pollutants such as O 3 , CO, NO 2 and PM 2.5 during 2015–2019 and
for the month of March 2020 and found that statistically significant reduction in
their levels. This is beneficial for cleaning the air and decreasing the deaths caused
by COVID-19 epidemic by reducing pressure on health equipment and hospitals
[12]. Bekbulat et al. (2020) found that particulate matter levels are 3% higher and
ozone levels are lowered by 4% than expected after 6 weeks of passing of orders
for stay at home. Further nitrogen dioxide is associated with traffic and showed
30% lower concentration during post-COVID [5]. Chen et al. (2020) in their study
across United States found non-uniform reductions of carbon monoxide (CO) up to
37% and nitrogen dioxide (NO 2 ) by 49% during the early phase of lockdown (15
March–25 April 2020) in comparison to a pre-lockdown mainly due to decrease in
transportation, potentially benefiting the health of the public [9]. Rodríguez-Urrego
and Rodríguez-Urrego (2020) in their study on 50 capital cities which are most
polluted in the world according to the WHO found that particulate matter PM 2.5
decreased by an average of 12% measured before and after the quarantine period
[55]. Saadat, Rawtani and Hussain (2020) stated that COVID-19 pandemic caused
the drop in water pollution and improvement in air quality in some parts of the world
mainly due to change in the life style of the people and shutting down of businesses
in order to control the virus [57]. Tracker (2020) stated that emissions reductions will
not be sustained unless recovery packages are implemented by the government to
enable low carbon societies and economies [70]. Shrestha et al. (2020) investigated
the six air pollutants between February, March 2019 and 2020 in 40 cities and found
PM 10 and PM 2.5 levels lower than in 2019 for the month of February and March 2020
175
restricting economic activities and personal mobility during COVID-19 improved the
air quality remarkably and brought down the PM 2.5 concentration by 25% which is
capable of averting premature deaths due to air pollution [28]. Marlier et al. (2020)
in their study quantified the changes in the concentration of air pollution in China for
the month January and February of 2019 and 2020. There was a reduction of 48% in
PM 2.5 concentrations, 11% in sulphur dioxide and 49% in nitrogen dioxide during a
3 week period after the Lunar New Year (LNY) in 2020 compared to 2019 which was
mainly due to measures taken for quarantine and decrease in transportation, industrial
pollution and economic activity during COVID-19 [42]. Cadotte (2020) compared
air quality of February 2019 and 2020 in six cities Shanghai, Wuhan, Milan, Hong
Kong, Seoul and Kyoto where restrictions were imposed due to COVID-19 and found
decline in major air pollutants indicating that air quality can be improved through
change in policy by the government [6]. Almond et al. (2020) in their study concluded
that COVID-19 had indefinite impacts on pollution in China. The improvement in
air quality was much less than that expected near the epicentre of the pandemic,
i.e. province of Hubei but the concentration of ozone increased in both absolute and
relative terms [1]. Kuzemko et al. (2020) found that the emission level recorded in
April, 2020 was as low as 10 years ago with Carbon dioxide emissions showing
reduction of 17% in April 2020 as compared to April 2019, due to reduction in
transport [36]. Connerton et al. (2020) studied the air pollution effects caused due
to social distancing and quarantine policies in four megacities: Paris in France, New
York and Los Angeles in the United States, Sao Paulo in Brazil by analysing the
levels of air pollutants such as O 3 , CO, NO 2 and PM 2.5 during 2015–2019 and
for the month of March 2020 and found that statistically significant reduction in
their levels. This is beneficial for cleaning the air and decreasing the deaths caused
by COVID-19 epidemic by reducing pressure on health equipment and hospitals
[12]. Bekbulat et al. (2020) found that particulate matter levels are 3% higher and
ozone levels are lowered by 4% than expected after 6 weeks of passing of orders
for stay at home. Further nitrogen dioxide is associated with traffic and showed
30% lower concentration during post-COVID [5]. Chen et al. (2020) in their study
across United States found non-uniform reductions of carbon monoxide (CO) up to
37% and nitrogen dioxide (NO 2 ) by 49% during the early phase of lockdown (15
March–25 April 2020) in comparison to a pre-lockdown mainly due to decrease in
transportation, potentially benefiting the health of the public [9]. Rodríguez-Urrego
and Rodríguez-Urrego (2020) in their study on 50 capital cities which are most
polluted in the world according to the WHO found that particulate matter PM 2.5
decreased by an average of 12% measured before and after the quarantine period
[55]. Saadat, Rawtani and Hussain (2020) stated that COVID-19 pandemic caused
the drop in water pollution and improvement in air quality in some parts of the world
mainly due to change in the life style of the people and shutting down of businesses
in order to control the virus [57]. Tracker (2020) stated that emissions reductions will
not be sustained unless recovery packages are implemented by the government to
enable low carbon societies and economies [70]. Shrestha et al. (2020) investigated
the six air pollutants between February, March 2019 and 2020 in 40 cities and found
PM 10 and PM 2.5 levels lower than in 2019 for the month of February and March 2020