Only 222 cities of the 6,475 analyzed had average air quality that met WHO’s standard. In the United States, IQAir found air pollution exceeded WHO guidelines by 2 to 3 times in 2021. “(Fine particulate matter) kills far too many people every year and governments need to set more stringent air quality national standards and explore better foreign policies that promote better air quality.”IQAirAbove: IQAir analyzed average annual air quality for more than 6,000 cities and categorized them from best air quality, in blue (Meets WHO PM2.5 guildline) to worst, in purple (Exceeds WHO PM2.5 guideline by over 10 times). It’s the first major global air quality report based on WHO’s new annual air pollution guidelines, which were updated in September 2021. China — which is among the countries with the worst air pollution — showed improved air quality in 2021.