Table 1.
Previous air pollution-COVID-19 empirical assessments.
| Author(s) | Country | Sample period | Air pollution variable(s) | Evidence on the effect of air pollution on COVID-19 lethality |
|---|---|---|---|---|
| Wu et al. [29] | 3087 counties in the USA | Up to April 22th 2020 | PM2.5 | Yes |
| Yongjian et al. [30] | 120 cities in China | January 23th-February 29th 2020, | PM2.5, PM10, SO2, CO, NO2 and O3 | Yes |
| Travaglio et al. [31] | 120 sites in England | February 1st to April 8th 2020 | NO2, NOx and O3 | Yes |
| Setti et al. [32] | 8 Italian regions | 10th February-29th February 2020, | PM10 | Yes |
| Conticini et al.[33] | Northern Italy | March 15th 2020 onward | PM10, PM2.5, O3, SO2 and NO2 | Yes |
Source: our elaborations.
Notes: “Yes” means that a significant correlation between air pollution levels and COVID-19 cases/mortality is confirmed.