Dhaka, capital city of Bangladesh, has been ranked the worst again in Air Quality Index (AQI).
Dhaka had a score of 242 around 8am on Tuesday (Nov 26), which means the air quality was very unhealthy during that time, news agency UNB reports.
India's Kolkata, Pakistan's Lahore and Mongolia's Ulaanbaatar occupied the next three spots with scores of 211, 198 and 198, respectively.
When the AQI value is between 201 and 300, every city dweller may begin to experience health effects.
Children, adults, and people with respiratory diseases are advised to avoid outdoor activities while everyone else is suggested to limit outdoor exertion in this situation, according to UNB.
The air quality is categorized as good when the AQI score remains below 50. The air is classified as moderate when the score is from 51 to 100. But when the number is between 101 and 150, the air is classified as unhealthy for sensitive groups.
According to UNB, the AQI, an index for reporting daily air quality, tells people how clean or polluted the air of a certain city is, and what associated health effects might be a concern for them.
Bangladesh's overcrowded capital has been grappling with air pollution for a long time. The air quality usually improves during monsoon.