India’s neighbour ranked as most polluted country in 2025. Check full list

Pakistan recorded the highest air pollution levels globally in 2025, with PM2.5 concentrations reaching up to 13 times above the safe limit set by the World Health Organization, according to a report released on Tuesday by IQAir.

According to the report, only 13 countries and territories maintained average PM2.5 levels within the WHO guideline of less than 5 micrograms per cubic metre in 2025, an increase from seven in 2024. However, 130 out of 143 monitored countries failed to meet the standard.

Bangladesh and Tajikistan ranked second and third among the most polluted countries. Chad, which was the most polluted in 2024, dropped to fourth place in 2025.


As per the report, this decline may reflect gaps in data rather than an actual improvement in air quality.

In March last year, the United States shut down a programme that collected pollution data from its embassies and consulates. The move affected data availability in several regions.

"The loss of the data in March made it appear there was a significant drop in PM2.5 levels (in Chad), but the fact of the matter is that we don't know," said Christi Chester Schroeder, lead author of the IQAir report.

Due to missing data, countries such as Burundi, Turkmenistan and Togo were excluded from the 2025 assessment.

At the city level, Loni in India recorded the highest pollution levels globally, with an average PM2.5 concentration of 112.5 micrograms per cubic metre. Hotan in China’s Xinjiang region followed with 109.6 micrograms. According to the report, all of the world’s 25 most polluted cities were located in India, Pakistan and China.

Globally, only 14% of cities met the WHO air quality standard in 2025, down from 17% in the previous year. The report linked rising pollution levels in some regions to factors such as Canadian wildfires, which impacted air quality across the United States and parts of Europe.

Some countries showed improvement. Australia, Iceland, Estonia and Panama met the WHO standard in 2025. Laos, Cambodia and Indonesia reported notable reductions in PM2.5 levels, largely due to wetter and windier La Nina conditions. Mongolia also saw a 31% drop in average concentrations to 17.8 micrograms per cubic metre.

Overall, 75 countries recorded lower PM2.5 levels compared to 2024, while 54 countries saw an increase, the report said.