Dust, not fog, behind Chattogram’s winter haze as PM2.5 spikes

Chattogram is usually expected to be covered in fog during winter. This year, however, the city is blanketed not by fog but by dense dust, with dangerous levels of fine particulate matter in the air.

Although the haze appears like fog to the naked eye, residents say it is dust. Sore throats, persistent coughs, eye irritation, and breathing difficulties have become common complaints among city dwellers.

Data from the Department of Environment and the AQICN air quality monitoring platform show that Chattogram's PM2.5 levels – microscopic dust particles harmful to human health – reached hazardous levels during November and December. On most days, the daily average concentration ranged between 50 and 150 micrograms per cubic metre, while on some days it exceeded 200 to 400 micrograms.

According to the World Health Organization's 2021 air quality guidelines, the safe annual average limit for PM2.5 is 5 micrograms per cubic metre, while the safe daily limit is 15 micrograms. Based on these standards, PM2.5 levels in Chattogram during November–December were 10 to 30 times higher than the safe limit.

Rising patients, mounting pressure on hospitals

Air pollution is having a direct impact on public health, doctors say.

Consultant Najmul Hasnain Naushad of Chest Disease Hospital, Faujdarhat, Chattogram, said 6,520 patients received treatment there in 2024 for breathing difficulties, asthma, and other respiratory illnesses. So far at the end of 2025, the number has risen to 9,166, an increase of around 40% compared to 2024.

Associate Professor Dr Rajat Sanker Roy Biswas of Chattogram Maa-O-Shishu Hospital said dust levels naturally rise during winter, and construction activity and vehicle emissions have worsened the situation.

"Respiratory problems, asthma, allergies, and long-term lung diseases are increasing," he said. "Children, older people, and those with existing respiratory conditions are most at risk."

Long-term exposure to polluted air can worsen disease severity and reduce the effectiveness of medication, he added, advising people to avoid unnecessary outdoor exposure, use masks, and keep indoor air clean.

Construction dust identified as main source

Ongoing development projects and road excavation across the city have been identified as the main sources of dust pollution.

During visits to several areas, road digging linked to the Chattogram Development Authority's one-kilometre expressway project was seen generating large amounts of dust as vehicles passed.

After a bridge collapsed on Bayazid Bostami Road on 7 August, Chattogram City Corporation began reconstruction and repair work, which is still ongoing. Dust levels have also increased due to Wasa pipeline installation in the Chuna Factory Mor area and sewerage projects across the city.

Heavy dust haze is now visible daily on major roads, including Barapole–Nimtala, Sadarghat–Majhirghat, Kadamtali–Barik Building, Barik Building–Customs Mor, EPZ–Cement Crossing, Bahaddarhat–Kalurghat route, Dewanhat, Pahartali Bazar–Alankar, and from Chawkbazar Kachabazar to Rahattarpul.

Mohammad Rashid, a resident of Lalkhan Bazar, said wearing a mask has become unavoidable. "I already have dust allergies, and the problem has become worse. Work requires standing in dust for long periods, and traffic congestion has increased," he said.

Authorities respond

Director of the Department of Environment's Chattogram metropolitan office Sonia Sultana said air pollution is being monitored regularly, and fines and legal action are taken when pollution exceeds permitted levels. 

"Monitoring of construction activities has also been increased," she said.

Chattogram Wasa Superintending Engineer and Sewerage Project Director Mohammad Ariful Islam said some dust generation is unavoidable during construction, but measures such as water spraying, fencing work sites, and covering construction materials are being used. 

"Dust control becomes difficult when roads are left without carpeting after work is completed," he added. 

Chattogram City Corporation Secretary Mohammad Ashraful Amin said dust spread cannot be fully avoided during development work, but regular cleaning operations are being carried out to reduce its impact.

Long-term risks

Health experts warn that long-term exposure to polluted air significantly increases the risk of heart disease, stroke, respiratory infections, asthma, and lung cancer.

Deputy Civil Surgeon of Chattogram Dr Mohammad Towhidul Anwar said respiratory illnesses are rising rapidly in urban areas due to air pollution. 

"Public awareness and coordinated action are essential to address the situation," he said.

Once known as a winter city of fog, Chattogram is now turning into a city of dust. Without swift and effective action, experts warn this silent pollution could develop into a major public health crisis.