Dhaka, the densely populated capital of Bangladesh, continues to gasp for fresh air as the city ranks the world’s third most polluted city.
Dhaka’s air quality index score was recorded 221 at about 8:59am on Tuesday, which is considered ‘very unhealthy’.
India’s Delhi, Pakistan’s Lahore and Uzbekistan’s Tashkent occupied the first, second and fourth spots with AQI scores of 762, 463, and 208, respectively, in the latest list of world cities.
AQI, an index for reporting daily air quality, is used by government agencies to inform people how clean or polluted the air of a certain city is, and what associated health effects might be a concern for them.
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 said to be ‘very unhealthy’, while a reading of 301 and above 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 been grappling with air pollution issues. Its air quality usually turns unhealthy during winter and improves during monsoon.
With the advent of winter, the city’s air quality starts deteriorating sharply due to the massive discharge of pollutant particles from construction works, rundown roads, brick kilns and other sources.
Air pollution consistently ranks among the top risk factors for death and disability worldwide. Breathing polluted air has long been recognised as increasing a person’s chances of developing heart disease, chronic respiratory diseases, lung infections and cancer, according to several studies.
