Source: Feng Li / Getty Images News via Getty Images
2. Beijing, China
> Air quality ranking April 8, 2022: 187, 2 worst among 95 major cities
> Avg. annual PM2.5 concentration (μg/m³) in 2021: 34.4
> Worst month in 2021: March (83.1)
> Avg. annual PM2.5 concentration in 2020: 37.5
> Total population in 2022: 21,333,332
Source: hamed / Flickr
1. Tehran, Iran
> Air quality ranking April 8, 2022: 206, 1 worst among 95 major cities
> Avg. annual PM2.5 concentration (μg/m³) in 2021: 31.7
> Worst month in 2021: January (50.0)
> Avg. annual PM2.5 concentration in 2020: 29.0
> Total population in 2022: 9,381,546
