Kolkata, India

Kolkata, India, ranks 8th with chronic pollution from coal power plants, heavy traffic, and open waste burning, worsened by winter inversions trapping pollutants. The city's PM2.5 of 70 µg/m³ is 30% higher than the national benchmark of 54 µg/m³, yet it is 12% cleaner than #7 Bamako's 75 µg/m³. This data reflects the 15 million inhabitants battling visible haze for 150 days annually.