India’s 5 cities among world’s top 10 most polluted places
Pakistan is the world's most polluted country in 2025, with PM2.5 concentrations up to 13 times the recommended WHO level
A recent report has placed India at the centre of a worsening global emergency, with several of its cities ranking among the most polluted on the planet. Uttar Pradesh's Loni is the world’s most polluted city with alarming PM2.5 levels.
According to the 2025 World Air Quality Report released by IQAir, a Swiss air quality technology company, Loni's PM2.5 level is almost 22 times the prescribed limit.
A total of five Indian cities were among the top 10 most polluted cities in the world, including Loni and Meghalaya's Byrnihat, followed by Delhi, Ghaziabad and West Bengal's Ula (Birnagar). In the second spot in the list is China's Hotan. Four cities in Pakistan also appear on the list of the “World's most polluted cities”.
The 2025 IQAir World Air Quality Report presents PM2.5 air quality data sourced from 9,446 cities spanning 143 countries, regions, and territories. The information is sourced from more than 40,000 regulatory monitoring stations and low-cost sensors, managed by a wide array of contributors.
The information on air quality is obtained from government agencies, universities, non-profit organizations, private enterprises, and engaged citizen scientists around the world.
Pakistan is the world's most polluted country in 2025, with PM2.5 concentrations up to 13 times the recommended WHO level.
As a matter of fact, all 25 of the world’s most polluted cities are located within India, Pakistan, and China - with India alone housing three of the top four. The Indian cities in the top four include Byrnihat on the Assam-Meghalaya border, Delhi and Mullanpur near Mohali.
The high concentration of air pollutants in these cities, apart from other ones that are highly polluted, reflect a toxic mix of rapid urbanisation, industrial emissions, vehicular pollution, and seasonal factors like crop burning.
The report said in 2024, 17% of global cities met the WHO annual PM2.5 guideline, but this declined to 14% in 2025.
According to the WHO, annual PM2.5 - fine particulate matter that gets deep inside the lungs - levels should not exceed 5 micrograms per cubic metre.
India does not feature among the handful of countries that comply, highlighting a systemic and persistent failure to control pollution levels.
For Indian cities, the numbers are not just statistics - they translate into a daily public health emergency.
Loni recorded an annual average PM2.5 concentration of 112.5 g/m, more than 22 times the WHO guideline and a nearly 23 percent increase from 2024. Such levels are linked to rising cases of respiratory illnesses, cardiovascular diseases, cancers and reduced life expectancy.
Northern India, particularly the Indo-Gangetic plain, remains a hotspot due to geographic and climatic factors that trap pollutants close to the ground.
Urban clusters like Delhi-NCR, where Loni is located, exemplify this crisis. Winter months worsen the situation as temperature inversions prevent pollutants from dispersing.
