A new report has revealed that nearly every country in the world has air quality that exceeds the World Health Organization’s (WHO) guidelines for harmful PM2.5 particles, with only seven nations meeting the recommended standards in 2024.
According to the annual survey by Swiss air quality technology company IQAir, Australia, New Zealand, and Estonia were among the few countries with an average PM2.5 level of no more than 5µg per cubic meter, joining Iceland and several small island nations.
The countries with the highest levels of pollution included Chad, Bangladesh, Pakistan, the Democratic Republic of the Congo, and India. In these nations, PM2.5 levels were at least 10 times higher than the WHO’s recommended limit, with Chad’s levels reaching up to 18 times the guideline. PM2.5, tiny particles small enough to enter the bloodstream, are linked to significant health risks and are responsible for millions of deaths each year. Experts say there are no safe levels of exposure to PM2.5.
“Air pollution doesn’t kill us immediately – it takes maybe two to three decades before we see the impacts on health, unless it’s very extreme,” said Frank Hammes, CEO of IQAir. “[Avoiding it] is one of those preventative things people don’t think about till too late in their lives.”
The report, which marks the seventh year of the annual survey, also highlights some positive trends. The proportion of cities meeting the PM2.5 standards increased from 9% in 2023 to 17% in 2024.
Notably, air pollution in India decreased by 7% between 2023 and 2024, despite it housing six of the ten most polluted cities globally. China also saw improvements in air quality, continuing a trend where PM2.5 pollution has nearly halved from 2013 to 2020. In Beijing, air quality is now comparable to Sarajevo, the capital of Bosnia and Herzegovina, which remains the most polluted city in Europe.
Zorana Jovanovic Andersen, an environmental epidemiologist at the University of Copenhagen, who did not contribute to the report, commented on the stark differences in air quality: “Huge disparities are seen even within one of the cleanest continents…there is a 20-fold difference in PM2.5 levels between the most and least polluted cities in eastern European and non-EU Balkan countries.”
