Dhaka’s air unhealthiest yet again, Wuhan 2nd and Delhi 3rd in AQI

Dhaka's air is once again the world's most polluted.

The capital's air quality index (AQI) was recorded at 269 at 10:11am today.

China's Wuhan and India's New Delhi occupied the next two positions, with AQI scores of 252 and 214, respectively.

An AQI between 201 and 300 is said to be "poor", while a reading of 301 to 400 is considered "hazardous", posing serious health risks to residents.

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".

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.