Pedestrians in Bangkok walk along the streets with handkerchiefs covering their noses. This is because nobody would like to inhale the unclean air into their body. As both residents and foreigners who have visited Bangkok know, Bangkok has one of the worst traffic in the world. This is due to the number of motor vehicles running on the roads which has increased significantly over the past few years. And without enough mass transit and road network, it led to traffic congestion. Moreover, since Bangkok is the capital city of Thailand, it is the center of civilization as well as economic growth. Therefore, the number of industries and factories are also growing. Motor vehicles and industries have contributed to the emission of pollutants into the atmosphere, causing air pollution which is perhaps one of the most serious environmental issues in Bangkok.
So what does air pollution mean? Air pollution is the stage in which the air contains gases, dust, fumes or odor in harmful amounts and could affect humans’, animals’, and plants’ health negatively.
Mobile source is one of the major sources of pollutants in Bangkok. The number of vehicles has been increasing dramatically over the past few years. It is also said that the automobile pollution is increasing together with an increase in the number of vehicles on the road in Bangkok. The Strategy and Evaluation Development has presented the latest information that in the year 2008, 26,417,353 vehicles were registered in Thailand. In Bangkok alone, 5,911,696 vehicles were registered. This factor, along with the lack of efficient mass transit system, has led to the city’s traffic problem. The average speed of traffic in the inner zone of Bangkok is as slow as 8-5 km per hour. Researches have shown that vehicles accounted for approximately 80% of NOx emissions, 54% of PM* (particulate matter) emissions and about 100% of hydrocarbon emissions.
According to a research paper on Fighting Urban