The extreme change in human behavior has most likely affected air quality worldwide. This article examines and compares pollution levels during the pre-COVID period (January '20 till March '20), the COVID-19 period (March 13–April 21st '20) as 'current' data, and 2017–2019 representing ‘historical’ data.
The PM2.5 reduction is larger in places where non-essential business closures were instituted early.
Sofia is an urban city and early in the pandemic, non-essential businesses were closed therefore the statistic would in some way apply to Bulgaria, too.
Don't get fooled, though. The PM2.5 has always been high because it is mainly affected by food industries and plantations which do not get closed during the lockdown period. And generally in Sofia during the colder months, the PM is very high and easily noticeable in the air because many people use personal transportation rather than public transport which will probably get more popular because of COVID. That is why it is important to know how to protect ourselves.
That is because of the damage the PM2.5 causes on the lungs and heart which are the primary organs attacked by this virus.
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