Dhaka:Dhaka ranked 5th among the world's most polluted cities on Thursday morning, with an Air Quality Index (AQI) score of 174 at 1025 am.
According to United News of Bangladesh, the air quality was classified as 'unhealthy', suggesting that the concentration of pollutants in the air had reached levels that could pose health risks to the general population, based on the AQI scale.
Pakistan's Lahore topped the list of polluted cities with an AQI score of 355, followed by India's Delhi at 271 and Kolkata at 208. The AQI scale categorizes readings from 101-150 as unhealthy for sensitive groups, 151-200 as unhealthy, 201-300 as very unhealthy, and scores above 301 as hazardous, posing serious health risks.
The AQI measures daily air quality, indicating pollution levels and potential effects on public health. In Bangladesh, air quality assessments focus on five major pollutants particulate matter (PM10 and PM2.5), nitrogen dioxide (NO2), carbon monoxide (CO), sulphur dioxide (SO2), and ozone.
The World Health Organization estimates that air pollution causes approximately seven million deaths globally each year, primarily due to stroke, heart disease, chronic obstructive pulmonary disease, lung cancer, and acute respiratory infections.