People of the urban areas of the country have, of late, been seen to wear protective masks on their faces whenever they are out on the streets of the metropolis. They certainly do not do so to evade the attention of their creditors, but just to protect themselves from the polluted air that has been increasingly getting polluted. 

It is time that the concerned authorities do something to keep the level of air pollution in and around the urban areas, especially those that have industrial zones around them.

The urban and semi-urban population of the country have, of late, been getting increasingly concerned about the worsening air pollution situation in the country, although the concerned authorities are yet to take matching steps to redress their concern or the physical dangers that they face. 

They continue, rather inexorably, as it were, to breathe toxic fumes emitted by faulty, badly or inadequately serviced motor vehicles and the chimneys of mills, factories and industries that dot the densely populated spots. Anyone having a look at the metropolis from a high-rise building is sure to get scared about the prospects that are far from bright. 

The vehicles that worsen the scenario are faulty buses, trucks, mini-buses two-stroke engined-auto rickshaws and motor-bikes, drivers of which often use impure fuels. From all these sources emit a great deal of carbon monoxide, hydrocarbons, nitrogen oxides, sulphur dioxide and lead particles. 

The Department of Environment (DOE) estimates that more than 80 per cent of more than 200,000 auto-vehicles on the streets of the metropolis emit dangerous black smoke - beyond the permissible limits. 

The two-stroke auto-rickshaws have been identified (popularly known as Baby taxis) as the worst culprits. According to official estimates, more 35,000 of them are doing more damage to the atmosphere of the capital city than anything else.

The increasing magnitude of air pollution in the Dhaka city has, meantime, drawn the attention of such international agencies as the International Development Association (IDA), which has approved US$ 177 million credit to help cope up with Dhaka’s worsening air pollution and traffic crisis. 

In the developed countries, methods for controlling air pollution include removing the hazardous material before it is used, removing the pollutant after it is formed, or altering the process so that the pollutant is not formed or occurs only at very low levels. Car exhaust pollutants can be controlled by burning the fuel as completely as possible, by recirculating fumes from fuel tank, carburettor, and crankcase, and by changing the engine exhaust to harmless substances in catalytic converters. Industrially emitted particulates may be trapped in cyclones, electrostatic precipitators, and filters. 

Pollutant gases can be collected in liquids or on solids, or incinerated into harmless substances. Not that environmentalists in Bangladesh do not know about these but they are yet to make a beginning in this regard. 

The Bangladesh Atomic Energy Commission (BAEC) scientists have calculated that about 50 tonnes of lead is emitted in and around Dhaka city per year. The density of lead in air, they have pointed out, during the dry season reaches 463 nanograms - one nanogram equalling one billionth of a gram per cubic meter - which happens to be highest in the world! There are reasons to be worried indeed! 

No wonder, increasing number cases of acute asthma and other respiratory diseases, fatigues, headaches, high blood pressure, various heart diseases and cancer among the urban population of the country are being detected with every passing day. 

Environmental activists also point to the textile and dying mills that burn or dispose of their solid wastes by way of unscientific burning. 

Tanneries, pulp and paper, cement manufacturing unit and fertiliser factories also continue to make their mindless contribution to the worsening air quality of the country - notwithstanding the very many legislations that have been made by the parliament. 

The DOE is apparently much too under-staffed, ill-equipped and handicapped by limitation of resources to the gigantic problem. 

The most important task of increasing public awareness is yet to reach even a reasonable magnitude. This continues to be so despite the fact that a World Bank (WB) report had recently attributed 15,000 premature deaths and several million cases of serious sickness in and around the metropolis to worsening air pollution.

Source: The Financial Express, 10 June,2001