8.1 million people worldwide died due to air pollution in 2021, making it the second leading risk factor for death.

8.1 million people worldwide died due to air pollution in 2021, making it the second leading risk factor for death, according to the Health Effects Institute's (HEI) fifth edition of the State of Global Air report. The report reveals that children under five are particularly vulnerable, accounting for over 700,000 deaths in 2021. Burning fossil fuels and biomass in sectors like transportation, residential homes, wildfires, and more caused more than 90% of global air pollution deaths.