Dhaka maintained a ‘moderate’ level of air quality on Monday morning (October 6), ranking 33rd among cities with the worst air pollution, according to the Air Quality Index (AQI). The capital recorded a score of 66 at 9:20am — identical to its reading on Sunday, when it ranked 31st globally.

An AQI score between 51 and 100 is classified as ‘moderate’, indicating that air quality is acceptable, though there may be a slight health concern for individuals who are unusually sensitive to air pollution.

The AQI categorises pollution levels as follows:

0–50: Good

51–100: Moderate

101–150: Unhealthy for sensitive groups

151–200: Unhealthy

201–300: Very unhealthy

301 and above: Hazardous

Tashkent (Uzbekistan), Kolkata (India), and Wuhan (China) topped the list on Monday with AQI scores of 195, 157, and 151 respectively, placing them in the ‘unhealthy’ category.

Bangladesh’s AQI is calculated based on five major pollutants: particulate matter (PM2.5 and PM10), nitrogen dioxide (NO?), carbon monoxide (CO), sulfur dioxide (SO?), and ozone (O?).

Air quality in Dhaka often worsens in the winter due to dry weather and increased pollutant concentration, while conditions tend to improve during the monsoon season.

According to the World Health Organization (WHO), air pollution causes around seven million premature deaths globally each year, linked to illnesses such as stroke, heart disease, chronic respiratory diseases, lung cancer, and acute infections.