The majority of our planet suffers from dirty air, according to a new report, with only 12 out 138 countries having air quality below WHO’s annual threshold of 5.0 micrograms per cubic meter of PM2.5 – a harmful particulate that’s 2.5 microns in diameter or smaller.
According to a new 2024 report by the Switzerland-based air pollution watchdog IQAir, most of the world has dirty air.
In their “2024 World Air Quality Report”, published on March 11, 2025, they report that only 12 countries out of 138 (that collectively use 40,000 air quality monitoring stations) have PM2.5 concentrations below the World Health Organization annual guideline of 5.0 μg/m³.
PM2.5 is fine particulate matter that’s less than or equal to 2.5 microns in diameter – reported in micrograms per cubic meter (μg/m³). PM2.5 is one of six key air pollutants recognized and monitored globally due to its significantly adverse effects on human health.
