Dhaka, the densely populated capital of Bangladesh, ranked seventh among the world’s most polluted cities on Friday morning, recording an Air Quality Index (AQI) of 117 at 9:10 am.

According to the AQI scale, the air quality was classified as “unhealthy for sensitive groups,” indicating potential health risks for vulnerable individuals.

Nepal’s Kathmandu, India’s Delhi, and Thailand’s Chiang Mai topped the list of most polluted cities, with AQI scores of 235, 231, and 165, respectively.

An AQI reading between 101 and 150 is considered “unhealthy for sensitive groups,” while 151–200 is deemed “unhealthy.” Levels between 201 and 300 are classified as “very unhealthy,” and readings above 301 are considered “hazardous,” posing serious health risks.

The AQI measures daily air quality, indicating how clean or polluted the air is and outlining potential health effects on the population.

In Bangladesh, AQI calculations are based on five major pollutants: particulate matter (PM10 and PM2.5), nitrogen dioxide, carbon monoxide, sulphur dioxide, and ozone.

Dhaka has long struggled with severe air pollution, which typically worsens during the winter months and improves during the monsoon season.

According to the World Health Organization, air pollution causes approximately seven million deaths globally each year, primarily due to stroke, heart disease, chronic respiratory illnesses, lung cancer, and acute respiratory infections.