Dhaka's air quality was marked as 'unhealthy for sensitive groups' on Wednesday morning. 

With an air quality index (AQI) score of 110 at 8:26am, Dhaka ranked 7th on the list of cities worldwide with the worst air quality, according to IQAir.

Jakarta of Indonesia, Santiago of Chile and Johannesburg of South Africa occupied the first three spots on the list, with AQI scores of 155, 154 and 150 respectively.

An AQI between 50 and 100 is considered ‘moderate’ with acceptable air quality. However, there may be a health concern for a very small number of people who are unusually sensitive to air pollution. AQI between 101 and 150 is considered ‘unhealthy', and between 201 and 300 is said to be 'very unhealthy', while a reading of 301+ is considered 'hazardous', posing serious health risks to residents.

In Bangladesh, the AQI is based on five criteria pollutants: particulate matter (PM10 and PM2.5), NO2, CO, SO2 and Ozone.

Dhaka has long grappled with air pollution issues. Its air quality usually turns unhealthy in the winter and improves during the monsoon.