Sylhet:Residents in the north-eastern divisional hub of Sylhet continue to breathe the cleanest air among the country's major urban regions, according to environmental data.
According to Bangladesh Sangbad Sangstha, data from the IQAir Real-Time City Ranking reveals that the Air Quality Index (AQI) in Sylhet sits at a moderate level of around 81 to 86, meaning the air is generally acceptable but can pose minor health risks to unusually sensitive individuals.
The yearly average air pollution data, generated by the Department of Environment (DoE), shows Sylhet had the cleanest air among all divisional cities in 2025 with 50.32 µg/m³ (microgram/cubic metre) of PM2.5. In contrast, Rangpur recorded the highest yearly average PM2.5 in 2025 at 105.83 µg/m³, followed by Rajshahi, Dhaka, Mymensingh, Chattogram, Khulna, and Barishal.
In Sylhet, higher annual rainfall and abundant greenery help wash particulate matter out of the atmosphere, though levels still remained 1.44 times above the national limit. Dr. Mohammad Abdul Motalib, DoE deputy director (air quality), attributed the relatively low air pollution level to Sylhet's geographical location and greenery.
A report by the World Bank highlights that while air pollution remains a nationwide challenge, the eastern regions, specifically the Sylhet division, consistently experience the lowest levels of fine particulate matter (PM2.5) in the country. On the other hand, cities like Dhaka, Rangpur, and Rajshahi register significantly higher concentrations of particulate matter.
Environmentalists credit Sylhet's clean air advantage to its unique geographic positioning, surrounded by expansive tea gardens and a hilled landscape, as well as a lower concentration of heavy industrial brick kilns. However, during the dry winter months, atmospheric inversions can temporarily worsen air quality.
Local civic groups, including Bangladesh Paribesh Andolon (BAPA), emphasize the need for active municipal management to maintain air quality. Challenges include unplanned construction dust, domestic waste management, and increasing vehicular traffic. The DoE's air quality monitoring network and standards categorize AQI scores to indicate different pollution levels, from 'Good' to 'Hazardous'.