, Feb. 1 -- Dhaka has once again topped the list of cities worldwide with the worst air quality. The AQI score of Dhaka's air quality was 254 at 9 am on Thursday.

Dhaka's air was classified as "very unhealthy", posing serious health risks to residents, according to the air quality index.

Ghana's Accra, India's Mumbai and Nepal's Kathmandu occupied the second, third and fourth spots on the list, with AQI scores of 191, 179 and 173, respectively.

As cold weather continues, Dhaka's air quality still 'unhealthy'

When the AQI value for particle pollution is between 101 and 150, air quality is considered "unhealthy for sensitive groups", between 150 and 200 is "unhealthy", between 201 and 300 is said to be "very unhealthy", while a reading ...