The New Nation - Internet Edition

Sheikh Arif Bulbon

The volume of poisonous particles in the city air has reached far beyond the permissible level for human body in recent years.

The Dhaka city dwellers are always at a serious health risk due to the highly polluted air, warned health experts.

The increasingly high concentration of toxic elements in the air is causing a foggy blanket in the city sky at present, according to the experts of Air Quality Management Project (AQMP) under the Department of Environment (DoE).

The AQMP, which has been monitoring the air quality of the city since 2002, has recently lunched a website to inform the people about the air quality on daily basis.

The website reveals that the air quality of the city is lethal for human body especially during winter and post winter.

The AQMP advised the city dwellers to stay indoors as much as possible during this time to avoid health hazards from the pollution.

According to the website, poisonous carbon monoxide, sulphur dioxide, nitrogen dioxide, suspended particulate matter (PM-10) and particulate matter (PM-2.5) exist in Dhaka's air beyond permissible level for human body.

Due to increase of PM-10 and PM-2.5, people lose lung function and suffer from chronic respiratory and cardiovascular diseases while nitrogen dioxide increase risks of bronchitis and pneumonia. Nitrogen dioxide causes respiratory infection.

Carbon monoxide reduces delivery of oxygen into the human body, creates severe headache and decreases visual perception and manual dexterity.

Permissible limit of PM-10 is 65 micrograms per cubic metre and for PM-2.5 it is 150 micrograms per cubic metre.

The implementation of the ban on two-stroke three-wheelers in 2003 made some temporary progress in reducing toxic elements from the air but has been marred by the functioning of old motorised vehicles and the brick kilns around the city.

Faulty vehicles are the largest source of air pollution. Only the diesel-run vehicles contribute about 60 per cent of such particles in the air, surveys of the AQMP revealed.

At least 70 per cent of the diesel-run vehicles, mainly buses and trucks, are emitting toxic particles beyond the permissible limit. Brick kilns in the northern edge of the city contribute at least 20 per cent to the air pollution.

There are 4,000 brick kilns around the city, which use tyres, wood and low-quality coal, emitting poisonous particles into the air. But no initiative has been taken yet to measure quantity of poisonous particles emitting from brick kilns.

The chimneys of the brick kilns made higher than 120-feet is not a solution to reducing the air pollution, said the AQMP officials.

The government banned running of buses more than 20 years old in the city but failed to keep those vehicles out of the city.

The height of brick kiln chimneys has been increased to reduce air pollution but the initiative failed as the government failed to ensure quality of fuel used in the kilns.

Mohammad Nasiruddin, Director of the AQMP, said: "Phasing out of the diesel-run old and faulty vehicles could reduce air pollution to half in the city."