Table 5.

Relationship between PM and COVID-19 infection.

S. No.	PM type	Country/Location	Period	Observation	Reference
1.	PM10 and PM2.5	China	January 26th - February 29th, 2020	PM2.5 has the potential of COVID-19 transmission	Li et al. (2020)
2.	PM10 and PM2.5	China	January 23rd - February 29th, 2020	Positively correlated with the risk of COVID-19 infection	Zhu et al. (2020)
3.	PM10 and PM2.5	China	January 25th - February 29th, 2020	PM2.5 increases the risk of COVID-19 infection	Jiang et al. (2020)
4.	PM10 and PM2.5	China	Upto March 22nd, 2020	Rise of every 10 $\mu g/m^3$ of PM10 and PM2.5 was linked with increased COVID-19 mortality rate with 0.24% and 0.26%, respectively	Yao et al. (2020b)
5	PM10 and PM2.5	United States	March 4th -April 24th, 2020	Showed significant correlation between PM and COVID-19	Bashir et al. (2020)
6.	PM10 and PM2.5	France	March 18th - April 27th, 2020	Direct association with COVID-19 mortality	Magazzino et al. (2020)
7.	PM10 and PM2.5	Middle Eastern Countries	n.a.	Indoor burning could enable the possible spread of SARS-CoV-2 virus droplets	Amoatey et al. (2020)
8.	PM10 and PM2.5	Italy	Upto March 31, 2020	Chronic exposure to PM2.5 causes alveolar ACE-2 receptor overexpression that links to COVID-19 infection	Frontera et al. (2020)
9.	PM10 and PM2.5	Italy	Upto April 27th, 2020	Favors the transmission of SARS-CoV-2 infection	Fattorini and Regoli (2020)
10.	PM10	Italy	February 10th - February 29th, 2020	Reported the presence of SARS-CoV-2 on PM	Setti et al. (2020)
11.	PM10	Italy	Upto April 7th, 2020	Transmission of COVID-19 is mainly by the air pollution	Coccia (2020)
12.	PM2.5	United States	Upto April 22nd, 2020	Increase of PM2.5 by 1 $\mu g/m^3$ was connected with an 8% of increased COVID-19 fatality	Wu et al. (2020)
13.	PM2.5	New York	March 1st - April 20th, 2020	PM2.5 was significantly associated COVID-19 infection, but not correlated with mortality	Adhikari and Yin (2020)

Note: n.a. – data not available.