Construction contributes 30% of Dhaka's air pollution: report

Dhaka is currently in the midst of a silent public health emergency from dangerous air pollution that has killed an estimated 24,000 people between 2005 and 2018. 

In a recent report from Eminence Associates for Social Development, Dr Md Shamim Hayder Talukdarm, CEO, and Md Wahiduzzaman, urban health officer, have compiled alarming facts and figures from multiple studies.

Research has found that construction is the highest contributor to Dhaka's pollution - 30% of the total - as the city sprawled from about 50 square kilometres in 1990 to 300 square kilometres today.

A near second, at 29%, is industrial pollution from the 1,000 brick kilns and other factories across the city. Vehicles emissions add a further 15%; "transboundary pollution" from neighbouring India, Pakistan and Nepal make up 10%.

Activities such as burning waste and wood-fired stoves represent the remainder 

"What's so troubling is how complex and wide-ranging the sources of Dhaka's air pollution are," says the investigator, Majumder A K. "Still, we are a long way from even starting to solve the problem."

Dhaka has consistently ranked in the top five cities with the worst air pollution worldwide. At best it has been classified as "unhealthy" with an AQI(Air Quality Index) score of 160 and above, 16 times the WHO annual air quality guideline value.

In a first study of its kind, analysing 12,000 Bangladeshis, the World Bank last year found that a 1% increase in exposure to PM2.5 above WHO guidelines led to a 12.8% rise in the probability of a person having breathing difficulties and a 20% rise in the probability of depression.

It also found those with higher incomes - one point higher on a socioeconomic indicator known as an asset score - had a 45% lower exposure

PM2.5 particles - small enough to bore through lungs, enter the bloodstream and damage internal organs - are linked to cardiovascular and respiratory diseases and cancer.

In order to reduce such elevated levels of pollution, many steps would need to be taken, albeit in the face of such economic growth it would be a task that the city of Dhaka would be hard pressed to do.

Stricter restrictions on fuels and vehicles allowed on the road would be beneficial in the fight to reduce ambient pollution levels in the air, with the removal of diesel fuel and old fume-producing engines being especially beneficial

Other initiatives involve stricter regulations for factories and building sites, holding organisations responsible for the quantity of pollution they produce, and potentially fining those who exceed harmful pollution and particulate matter thresholds.

Although there are undoubtedly complex factors involved, implementing these initiatives would be a positive step towards improving Dhaka's air quality and raising its PM2.5 and US AQI readings