<div><b><span style="font-size: 1rem;">With an air quality index (AQI) score of 37 at 11am Sunday, the metropolis ranked 49th in the list of world cities with the worst air quality.</span><br></b></div><div><br></div><div>An AQI between 0 and 50 is considered "good," 50 and 100 "moderate," and 101 and 200 "unhealthy," particularly for sensitive groups.</div><div><br></div><div>Similarly, 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.</div><div><br></div><div>Pakistan's Karachi, Serbia's Belgrade, and Italy's Milano occupied the first three spots in the list, with AQI scores of 159, 157, and 157, respectively.</div><div><br></div><div>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.</div><div><br></div><div>In Bangladesh, the AQI is based on five criteria pollutants – Particulate Matter (PM10 and PM2.5), NO2, CO, SO2 and Ozone.</div><div><br></div><div>Dhaka has long been grappling with air pollution issues. Its air quality usually turns unhealthy in winter and improves during the monsoon.</div><div><br></div><div>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.</div><div><br></div><div>According to 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. UNB</div><div><br></div><div>bnbd24/kh</div>