Pakistan was the world’s smoggiest country in 2025 with concentrations of hazardous fine particles known as PM2.5 up to 13 times higher than the World Health Organization’s (WHO’s) recommended level, a report finds.

In its annual report published on Tuesday, IQAir, a Swiss air quality monitoring firm, said only 13 countries and territories managed to keep their average fine particulate levels below the WHO guideline, but that number was up from seven in 2024.

IQAir sourced data from 9,446 cities in 143 countries, regions and territories. Overall, 130 of 143 monitored countries and territories failed to meet the WHO standard.

That standard is based on a measurement of fine particulate matter in the air of 2.5 microns or less in diameter. The WHO standard for healthy air quality is an average PM2.5 of no more than 5 microgrammes per cubic metre. Pakistan’s PM2.5 level was 67.3 microgrammes.

Pakistan’s average PM2.5 concentration in 2024 was 73.7 microgrammes.