Lahore ranked first in world's most polluted cities
Lahore, Pakistan's cultural capital, has been renamed the as the most polluted city in the world with a PM or Particulate Matter index of 423
Karachi, the financial capital of Pakistan, also ranks 7th in the index.
New Delhi, India is ranked the second most polluted city in the world with an air pollution index of 229. Kathmandu, Nepal is ranked third in the list with a PM index of 178.
Colombo, Sri Lanka is ranked 612 in the list of most polluted cities in the world reflecting that the air pollution in Sri Lanka is minimal.