Pakistan emerged as the world's most polluted country in 2025, while Loni in India was identified as the most polluted city globally, according to a new report released by Swiss air quality monitoring firm IQAir.
The report found that Pakistan recorded concentrations of hazardous fine particulate matter (PM2.5) up to 13 times higher than the safety threshold set by the World Health Organization. Loni, located in India's Uttar Pradesh, topped the list of the world's most polluted cities with average PM2.5 levels of 112.5 micrograms per cubic metre, followed by Hotan in China's Xinjiang region at 109.6 micrograms.
Globally, air quality remained a major concern, with 130 out of 143 monitored countries and territories failing to meet the WHO's recommended limit of 5 micrograms per cubic metre. Bangladesh and Tajikistan ranked second and third among the most polluted countries, respectively.
Also Read: Middle East Volatility Could Accelerate Global Green Energy Shift, Says Ex-Niti Aayog Trade Head
Chad, which was statistically the most polluted country in 2024, stood at fourth place in 2025. However, the report cautioned that this apparent improvement may be misleading due to incomplete data.
“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,” news agency Reuters quoted Christi Chester Schroeder, lead author of the IQAir repor, as saying.
The data gap follows a decision by the United States government to shut down a global air quality monitoring programme that relied on embassy and consulate readings, citing budget constraints. As a result, several countries, including Burundi, Turkmenistan and Togo, were excluded from the 2025 analysis.
The report also highlighted that the world's 25 most polluted cities were all located in India, Pakistan and China, underscoring the severity of air quality challenges across South and East Asia.
Also Read: Delhi vs Mumbai: Infrastructure To Pollution — 2026 Budget Comparison | Infographic Story
Only 14% of cities worldwide met WHO air quality standards in 2025, down from 17% a year earlier. Factors such as Canadian wildfires contributed to rising PM2.5 levels across the United States and even parts of Europe.
On a more positive note, 13 countries and territories managed to meet WHO guidelines in 2025, including Australia, Iceland, Estonia and Panama. Countries such as Laos, Cambodia and Indonesia recorded notable improvements in air quality, largely due to wetter and windier La Niña conditions, while Mongolia saw PM2.5 concentrations fall by 31% year-on-year.
Overall, 75 countries reported a decline in PM2.5 levels compared to 2024, while 54 recorded worsening air pollution, according to IQAir.
Essential Business Intelligence, Continuous LIVE TV, Sharp Market Insights, Practical Personal Finance Advice and Latest Stories — On NDTV Profit.