Dhaka, the densely populated capital of Bangladesh, ranked first among the world’s most polluted cities on Thursday morning, recording an Air Quality Index (AQI) of 271 at 9:13am. The city’s air was classified as ‘very unhealthy’, indicating a serious health threat, according to the AQI report, on Thursday.  Bishkek in Kyrgyzstan, Karachi in Pakistan, and Kolkata... Details