5 of top 10 most polluted cities in India
What's the story
Loni in Uttar Pradesh has been named the world's most polluted city in 2025, according to the latest World Air Quality Report by IQAir. The report was released on March 24 and highlights alarming PM2.5 levels in Loni. The World Health Organization (WHO) recommends a PM2.5 concentration of less than five micrograms per cubic meter, meaning Loni's levels are nearly 22 times higher than this limit.
Pollution hotspots
Other Indian cities in top 10
The report also lists four other Indian cities among the top 10 most polluted in the world. Byrnihat in Meghalaya is ranked third with a PM2.5 level of 101.1, while Delhi and Ghaziabad are ranked fourth and fifth with levels of 99.6 and 89.2, respectively. Ula (Birnagar) in West Bengal is ranked 10th with a PM2.5 level of 86.8 micrograms per cubic meter.
Report coverage
Report based on PM2.5 data from over 9,400 cities
The 2025 IQAir World Air Quality Report is based on PM2.5 data from 9,446 cities across 143 countries and territories. The data was collected from over 40,000 regulatory monitoring stations and low-cost sensors operated by various contributors. These include government agencies, universities, non-profit organizations, private companies, and citizen scientists worldwide.
Pollution leaders
Pakistan most polluted country
Pakistan has been named the world's most polluted country in 2025, with PM2.5 levels up to 13 times higher than the WHO-recommended level. The report found that only 14% of global cities met the WHO's annual PM2.5 guideline in 2025, a decline from 17% in 2024. Only French Polynesia, Puerto Rico and other select regions met these standards, while almost 91% of countries exceeded them.