World Air Quality Report 2021 – UPSC GS3
World Air Quality Report 2021: Report presented an overview of the state of global air quality in 2021. Report prepared by IQAir, a Swiss group that measures air quality levels based on the concentration of Particulate Matter (PM) 2.5. Need of World Air Quality Report: Air pollution is now considered to be the world’s largest environmental health threat, accounting for seven …