Dhaka ranked fifth among 126 cities worldwide in air pollution on Monday, with an Air Quality Index (AQI) score of 169, indicating unhealthy air quality.
Data from Swiss air quality monitoring organisation IQAir showed that the Bangladeshi capital recorded the fifth-highest pollution level on October 26.
India’s Delhi topped the list with an AQI score of 203, indicating very unhealthy air quality. Pakistan’s Lahore ranked second with a score of 197, followed by Karachi at 183. Vietnam’s Hanoi stood fourth with a score of 172, while Dhaka ranked fifth.
According to IQAir’s scale, an AQI score between 0 and 50 indicates good air quality, while a score of 51–100 is considered moderate. Scores between 101 and 150 are classified as unhealthy for sensitive groups.
An AQI between 151 and 200 indicates unhealthy air quality, while scores from 201 to 300 are considered very unhealthy. Readings above 300 fall into the hazardous category.
In Bangladesh, the AQI is calculated using five pollutant indicators: particulate matter (PM10 and PM2.5), nitrogen dioxide (NO2), carbon monoxide (CO), sulphur dioxide (SO2) and ozone (O3).
A 2019 report by the Department of Environment and the World Bank identified brick kilns, vehicle emissions and dust from construction sites as three major sources of air pollution in Dhaka.
According to the World Health Organization, air pollution contributes to increased deaths from stroke, heart disease, chronic obstructive pulmonary disease, lung cancer and acute respiratory infections. The organisation estimates that air pollution causes around seven million deaths worldwide each year.