Table 10.
Relative percentage difference of pollutants before and during the lockdown in different regions of the world [115].
| Pollutants | Region | Before Lockdown | During Lockdown | Relative Percentage Difference (%) |
|---|---|---|---|---|
| SO2 (µg/m3) | Hubei (China) | 15.81 | 13.83 | −13.36 |
| SO2 (DU) 1 | Malaysia | 1.42 | 0.99 | −35.68 |
| Sale (Morocco) | 6.6 | 3.3 | −0.49 | |
| CO (ppbv) 2 | Chennai (India) | 44.1 | 45.2 | −2.46 |
| Delhi (India) | 1.03 | 0.72 | −30.35 | |
| Hubei (China) | 1.207 | 1.02 | −16.79 | |
| Kolkata (India) | 0.6 | 0.5 | −18.18 | |
| Malaysia | 0.8 | 0.49 | −48.06 | |
| PM2.5 | Chennai (India) | 29.38 | 27.33 | −7.23 |
| Delhi (India}) | 80.51 | 37.75 | −53.11 | |
| Hubei (China) | 81.83 | 65.81 | −21.70 | |
| Malaysia | 32.3 | 22.34 | −36.46 | |
| Sao Paulo (Brazil) | 12.9 | 12.5 | −3.6 | |
| Wuhan (China) | 65.5 | 40.11 | −48.08 |
1 DU: Dosbin Unit, ppbv: 2 Parts per billion by volume