Dhaka:Dhaka's air quality deteriorated to a 'very unhealthy' level on Friday morning, with an Air Quality Index (AQI) score of 203 at 840 am. This placed the capital city fourth among the world's most polluted cities, According to AQI scale.
According to United News of Bangladesh, the 'very unhealthy' air quality level indicates that everyone, regardless of their health condition, may experience more serious health effects or discomfort from air pollution. Even short-term exposure can affect anyone's health.
Pakistan's Lahore topped the list of polluted cities with an AQI score of 456, followed by India's Delhi at 251 and Kolkata at 221. On the previous day, Dhaka ranked fifth in the world for pollution, recording an AQI score of 174 at 1025 am.
The AQI scale categorizes air quality with readings of 101-150 considered unhealthy for sensitive groups, scores of 151-200 indicating unhealthy air quality, readings of 201-300 classified as very unhealthy, and scores above 301 deemed hazardous, posing severe health risks.
In Bangladesh, air quality assessment is based 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 contributes to approximately seven million deaths globally each year, primarily from stroke, heart disease, chronic obstructive pulmonary disease, lung cancer, and acute respiratory infections.