Dhaka, Feb. 11 -- Dhaka, the overcrowded capital city of Bangladesh, has ranked first on the list of cities with the worst air quality with an AQI score of 392 at 9am on Monday. The air was classified as "hazardous," referring to an alarming health risk to residents, according to the AQI index.Though Sunday's air quality was marked as very unhealthy with an AQI score of 201, the air worsened on Monday marking "hazardous."When the AQI value for particle pollution is between 50 and 100, air quality is considered "moderate," usually sensitive individuals should consider limiting prolonged outdoor exertion, between 101 and 150, air quality is considered "unhealthy for sensitive groups," between 150 and 200 is "unhealthy," between 201 and 300 is...