Dhaka, Nov. 17 -- Dhaka's air quality continued to be in the 'unhealthy' zone as winter is approaching.

With an air quality index (AQI) score of 161 at 9:03am today (Thursday), Dhaka ranked sixth in the list of cities worldwide with the worst air quality.

An AQI between 101 and 200 is considered 'unhealthy', particularly for sensitive groups.

India's Delhi, Pakistan's Lahore, and India's Kolkata occupied the first three spots in the list, with AQI scores of 261, 246 and 204, respectively, reports UNB.

An AQI between 201 and 300 is said to be 'poor', while a reading of 301 to 400 is considered 'hazardous', posing serious health risks to residents.

In Bangladesh, the AQI is based on five criteria pollutants -- Particulate Matter (PM10 ...