DHAKA, April 29 -- Dhaka ranked sixth on the list of cities worldwide with the worst air quality, with an AQI score of 152 at 9:00 am this morning.

Dhaka's air was classified as 'unhealthy', according to the air quality index.

Iraq's Baghdad, India's Delhi and Nepal's Kathmandu occupied the first three spots on the list, with AQI scores of 401, 266, and 169 respectively.

Rain expected in Chattogram and Sylhet within 24 hours

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 of 301+ is considered 'hazardous', posing serious health risks to residents.

The AQI...