AT 8:30 in the morning, Gulistan grinds to a halt. Buses idle in thick columns, rickshaws wedge through slivers of space, and motorcycles sputter past, releasing fumes into the already noxious air. For the office-goer inching forward in the gridlock, it may seem like just another Dhaka morning. But what fills their lungs is far from benign — it is a cocktail of toxic gases and ultrafine particles, invisible yet deadly. According to the Department of Environment, over a third of Dhaka’s fine particulate matter (PM2.5) during rush hour stems from vehicular emissions alone. The World Health Organization draws an even starker parallel: breathing in Dhaka is equivalent to smoking 1.7 cigarettes daily.
The science is unequivocal. Dhaka’s air is saturated with multiple pollutants, each with its chain of destruction. The most damaging among them — PM2.5 — consists of particles small enough to evade the body’s natural filters and embed deep in the lungs. Originating from diesel combustion, construction sites, brick kilns and unpaved roads, these particles inflame lung tissue, scar the alveoli and even enter the bloodstream. Long-term exposure has been linked to chronic bronchitis, lung cancer and heart disease.
Nitrogen oxides, released by vehicles burning fuel at high temperatures, further complicate the air’s chemistry. When nitrogen dioxide interacts with sunlight and volatile organic compounds, it forms ozone — a corrosive gas that attacks the lining of the lungs and intensifies asthma. Sulphur dioxide, mainly from low-grade fuel and coal, reacts with atmospheric moisture to produce acid rain, damaging crops, corroding infrastructure and poisoning water bodies. Carbon monoxide, a product of incomplete combustion, displaces oxygen in the bloodstream and can be lethal in high concentrations. Then there are the VOCs themselves — benzene, formaldehyde, xylene — many of which are known carcinogens.
The issue of lead, though ostensibly resolved with the ban on leaded petrol, still looms large. In slums near informal battery recycling units, lead-tainted dust contaminates the air and soil. Children, most at risk, absorb this neurotoxin readily. Recent studies indicate that over 80 per cent of children in Dhaka’s poorest neighbourhoods have elevated blood lead levels — linked to cognitive impairment and reduced IQ.
Scientific data confirms the scale of the crisis. A BUET study recorded PM2.5 concentrations peaking at 550 µg/m³ in Farmgate and Mohammadpur during traffic surges. The WHO’s safe limit stands at just 50 µg/m³. This elevenfold excess is not a seasonal aberration — it is the everyday reality. PM2.5 triggers oxidative stress by generating reactive oxygen species in the lungs. The ensuing inflammation affects not only the respiratory system but cascades into cardiovascular strain, impaired brain development, and even neurodegenerative conditions.
Children are the silent victims. Their lungs and brains, still in critical stages of development, suffer irreversible damage. At Dhaka Children’s Hospital, nearly half of the children examined now exhibit signs of developmental delay. Asthma among children has surged by 65 per cent in the past five years. In lower-income areas, the situation is worse. Monitoring data show that PM2.5 levels are on average 45 per cent higher in informal settlements near roads than in more affluent zones. This is environmental injustice at its starkest: the poorest are forced to breathe the most poisonous air.
The pollutants do not operate in isolation. They interact with each other, producing secondary compounds often more hazardous than their precursors. PM2.5 acts as a delivery mechanism, ferrying heavy metals and carcinogens directly into the lungs. Nitrogen and sulphur oxides combine with ammonia from sewage and food waste to form ammonium salts, adding to the particulate burden. During winter, a temperature inversion traps these pollutants close to the ground, choking the city in visible smog. These interactions explain why minor emissions reductions often fail to improve air quality meaningfully. Without systemic change, Dhaka’s air remains dangerously unpredictable.
Yet the solutions are known, tested, and technologically within reach. Transitioning to electric vehicles would sharply reduce emissions. Each electric bus alone could offset ten tonnes of CO2 annually. But Dhaka lacks the infrastructure — fewer than 50 charging stations exist for a vehicle population exceeding 2.8 million. Investment in EV infrastructure is long overdue.
Upgrading fuel standards offers another proven route. Bangladesh still uses Euro-2 fuel, which contains 500 ppm of sulphur. Shifting to Euro-6, with just 10 ppm, could slash PM2.5 and nitrogen oxide emissions drastically. Jakarta’s move to Euro-4 in 2021 reduced its SO2 levels by 40 per cent. Bangladesh could follow suit, but it requires political will and regulatory enforcement.
Urban greening must also play a central role. Trees absorb pollutants and cool the environment. Increasing green coverage by 20 per cent could reduce PM2.5 levels by up to 14 per cent. Dhaka, with its shrinking parks and encroached canals, needs urgent reforestation and restoration of green corridors.
Cycling and walking remain underutilised despite the city’s flat terrain. Evidence from Bogotá shows that well-planned cycling infrastructure reduced urban air pollution by 18 per cent. Dhaka has no such lanes and continues to prioritise motorised transport. A shift towards non-motorised mobility, combined with safer public transport, could dramatically lower emissions.
Finally, regulation of small industries and battery recyclers is critical. Without strict environmental oversight, these operations will continue to emit VOCs and expose workers and residents to lead. The government must treat environmental protection as a matter of national health security, not bureaucratic formality.
The cost of ignoring the crisis is no longer speculative. If emissions continue unchecked, the UN warns that by 2030, Dhaka’s air may reach toxicity levels comparable to indoor coal smoke. The International Centre for Diarrhoeal Disease Research, Bangladesh estimates that over 3,000 children each day experience permanent damage to their lungs and brains. The economic toll is just as severe. The World Bank has projected that South Asia could lose over 10 per cent of its gross domestic product by 2060 due to air pollution-related impacts — with Dhaka among the worst affected due to its urban density and chaotic development.
Air pollution in Dhaka is not a technological problem — it is a governance failure. The science is clear. The tools are available. What remains absent is decisive leadership. This is not merely an environmental issue — it is a question of public health, economic stability, and intergenerational justice. Every breath taken in this city is a measure of how deeply we have allowed inertia and neglect to shape our policies. The air is toxic. The evidence is overwhelming. The choice is ours.
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Arghya Protik Chowdhury is a student of environmental science at the Bangladesh University of Professionals.