The densely populated capital of Bangladesh continues to wait for cleaner air, despite slipping a couple of notches in the list of world cities with the worst air quality.
Dhaka has, in fact, been ranked the fourth-most polluted city in the world. The capital's air quality index (AQI) was recorded at 188 around 10.15am on Thursday. The air was classified as ‘unhealthy’.
India’s Delhi, Mongolia’s Ulaanbaatar and Pakistan’s Lahore occupied the first three slots in the list of cities with the worst air quality with AQI scores of 376, 243 and 233, respectively.
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.
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.
A report by the Department of Environment (DoE) and the World Bank in March 2019 pointed out that the three main sources of air pollution in Dhaka "are brick kilns, fumes from vehicles and dust from construction sites".
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.
As per the World Health Organization (WHO), air pollution kills an estimated seven million people worldwide every year, largely as a result of increased mortality from stroke, heart disease, chronic obstructive pulmonary disease, lung cancer and acute respiratory infections.