HCM CITY — One of the most urgent issues currently affecting Vietnamese cities and their inhabitants is the widespread pollution of the very air they breathe. With a burgeoning population of motorcycles, cars, trucks and motorised three-wheel vehicles, the quality of air in Viet Nam’s 623 urban centres is rapidly deteriorating.

The short and long-term implications of this situation for human health are alarming. This alone should be sufficient to warrant immediate action to curb the systems, policies and behaviours that are perpetrating the problem. The other very real, but less vocal, victim in this equation is the environment, which is struggling to absorb the pressures we exert on it daily.

In 1999, 23 per cent of Viet Nam’s population was located in urban centres. That figure is projected to zoom to 45 per cent by 2020. And there is a direct relationship between the level of urbanisation, the number of vehicles on the road and the number of kilometres driven. Evidence the dramatic increase in two – and three-wheelers in HCM City, from 866,000 in 1993, to more than 1,600,000 in 2000, concomitant with the rapid urban growth rate of 12 per cent per annum. The result is high population density and ultimately, severe air pollution.

Transport is one of the primary causes of air pollution in urban centres such as HCM City. Industries such as thermal power, chemical, building material production, and mineral processing follow closely behind. Vehicles are responsible for emitting a number of noxious gases that are harmful to human health – carbon monoxide, hydrocarbons, nitrogen oxides, ozone (photochemical smog), lead and fine/coarse dust particles.

The list of health hazards is long and ranges from respiratory problems such as aggravation of asthma, sinus congestion and inflammation of the mucous membranes, to more debilitating conditions such as reproductive toxicity and neurodevelopmental retardation.

Vehicular emissions are heavily concentrated at the urban street level where people live, work and play. As is often the case, poor people and those with limited mobility such as the young and old, tend to suffer the most.

Children tend to be the most disadvantaged since many chemicals, lead in particular, target the central nervous system and are able to enter the bloodstream through juveniles’ incompletely developed blood-brain barrier.

And what of the environmental consequences? All the chemicals that are associated with vehicular emissions come under the umbrella term of "greenhouse gases". The Enhanced Greenhouse Effect refers to an artificial change in the mixture of gases that make up the earth’s atmosphere. The blanket of air that surrounds our planet becomes more effective at trapping heat and the result is global warming. When we warm the earth in such an unnatural fashion we jeopardise the delicate balance within our environment.

Global warming is already causing unpredictable climate variability. An increase in severe weather events will have a devastating impact on Viet Nam, given its precarious equatorial and coastal location. For the people of Viet Nam, this will mean more frequent violent rains and storms, floods, droughts and forest fires. An increase in the frequency and severity of extreme weather events is likely to have a direct impact on agricultural production and our ability to sustain ourselves through the provision of adequate food, clothing and shelter.

But the future does not have to be all doom and gloom. The way to abate the damage caused by the pollution and degradation of the air is to directly remove the source. Actions in neighbouring Asian countries to reduce air pollution have focused on incorporating emission control standards and technologies, such as catalytic converters, at the production stage.

Other approaches to tackle the problem include changing the type and quality of fuel available, improving maintenance regimes through vehicle inspection programme, the use of taxation and pricing tools, encouraging alternative modes of transport and investment in cleaner technologies.

Viet Nam has recently implemented a phase out programme for leaded petrol, but this should only be considered a first step in this uphill battle for clean change, and should be complemented by additional tools and a strategically planned regulatory framework.

Winning the battle against air pollution requires the combined actions of governments, the private sector and the community.

The benefits of decreased air pollution would be enormous, with a better quality of life and an increased life span for everyone, and a healthier, more productive environment for life. A few small changes in your behaviour can go a long way to improving conditions for everyone. — VNS

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