World Air Quality Report 2025 | 27 Mar 2026

Why in News? 

The 8^th annual World Air Quality Report 2025, released by IQAir, ranked India as the sixth most polluted country in the world based on average PM2.5 concentration levels. 

Key Points 

• India Ranking: India ranked 6^th among 143 countries in terms of PM2.5 pollution levels in 2025 with a national average PM2.5 concentration of 48.9 µg/m³—almost ten times higher than the WHO’s safe limit of 5 µg/m³. 
  • Loni in Uttar Pradesh was the most polluted city, with an annual average PM2.5 concentration of 112.5 µg/m³, marking a nearly 23% rise from 2024 and exceeding the WHO guideline by over 22 times. 
  • 66 of the world’s 100 most polluted cities are in India, including major cities like Delhi, Byrnihat, and Ghaziabad. 
  • New Delhi continued to rank as the most polluted capital city in the world for the eighth consecutive year. 
• Key findings: 
  • Only 14% of cities worldwide met the annual PM2.5 guideline of 5 µg/m³ set by the World Health Organization, a decrease from 17% recorded in the previous year. 
  • Only thirteen countries/territories met the annual average PM2.5 guideline prescribed by the World Health Organization. 
  • 130 out of 143 countries and territories (about 91%) recorded PM2.5 levels higher than the annual guideline value set by the World Health Organization. 
  • The five most polluted countries were Pakistan (67.3 µg/m³), Bangladesh (66.1 µg/m³), Tajikistan (57.3 µg/m³), Chad (53.6 µg/m³), and the Democratic Republic of the Congo (50.2 µg/m³). 
  • Nieuwoudtville in South Africa was recorded as the world’s cleanest city, with an annual average PM2.5 concentration of 1.0 µg/m³.