City pollution at ‘national disaster’ level

Bangkok must upgrade its ultra-fine dust pollution problem to “national disaster” level in order to strengthen protections against its far-reaching health impacts, ranging from heart and brain disorders to cancer.

The call was made yesterday by former Pollution Control Department chief Supat Wangwongwattana, who is worried the threat will not be tackled seriously at its root cause.

Cars and other road vehicles are seen as the primary cause of pollution in the city. Their dust emissions have exceeded “harmful” levels in the capital since last month.

PM2.5 is a major concern as these particles are smaller than the width of a single human hair and bury deep inside the lungs, causing serious respiratory problems.

They can also “enter veins and instigate some [negative] reactions” causing high blood pressure and deep vein thrombosis, Disease Control Department chief Suwanchai Watthanayingcharoenchai warned yesterday.

These conditions can lead to coronary artery disease, strokes and, in the long term, become a precursor to cancer.

Cars, mostly with diesel-powered engines, and factories contribute 52% of the pollutants in the capital, followed by 35% from outdoor burning, Mr Supat said. The rest is brought on by freak weather conditions and other sources.

Mr Supat, an air environment expert and Thammasat University lecturer, insisted Bangkok must limit the number of lorries in city areas and better cope with poorly managed traffic congestion, fuelled by the increasing number of vehicles.

He suggested authorities adopt a threemonth measure, from February to April every year, to extend areas where lorries are allowed to run only during certain hours.

PM2.5 levels often peak during the dry season, especially in the first few months of the year.

If the measure fails to curb dust levels, officials should intensify vehicle controls to cover small trucks during rush hours and even private cars. The latter with even, or odd, number plates should be barred from some city roads on alternate days, he said.

The ultimate solution would see a complete ban on outdoor burning especially in Bangkok’s suburbs and neighbouring provinces, pundits say.

Mr Supat said more drastic efforts would be needed in the future to improve the traffic flow and better control emissions from construction sites in the capital.

Some have called to ban temple crematoria that emit smoke.