Dhaka: Dhaka, the densely populated capital of Bangladesh, ranked third among the world’s most polluted cities on Wednesday morning, recording an Air Quality Index (AQI) of 222 at 10:20 am. Today, the city’s air was classified as ‘very unhealthy’, indicating a serious health threat, according to the AQI report.
According to United News of Bangladesh, Lahore in Pakistan, Dakar in Senegal, and Kolkata in India occupied the first, second, and fourth spots on the list, with AQI scores of 254, 225, and 201 respectively. The AQI scale categorizes a reading between 50 and 100 as ‘moderate’, which is generally acceptable though sensitive individuals should limit prolonged outdoor exertion. Levels of 101-150 are ‘unhealthy for sensitive groups’, 151-200 is ‘unhealthy’, 201-300 is ‘very unhealthy’, and readings above 301 are considered ‘hazardous’, posing severe health risks.
The AQI, which reports daily air quality, informs residents how clean or polluted the air is and highlights potential health effects. In Bangladesh, the AQI is calculated based on five key pollutants: particulate matter (PM10 and PM2.5), nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), and ozone. Dhaka has long struggled with air pollution, with air quality usually deteriorating in winter and improving during the monsoon season.
The World Health Organization (WHO) estimates that air pollution causes about seven million deaths worldwide each year, primarily from stroke, heart disease, chronic obstructive pulmonary disease, lung cancer, and acute respiratory infections.