| Summary: | 碩士 === 國立陽明大學 === 環境衛生研究所 === 88 === There are many traffic problems caused by increased amount of vehiclesin Taipei. The government established some strategies to solve these problems. Establishing exclusive bus lanes is one of the important implement, but which may bring another suffer for people. In addition , an alternative of anti-knocking chemical-MTBE has been proved to be an animal carcinogen recently, and has raised public concern as well.
The purpose of this study were to realize the concentrations and the spacial distributions of airborne volatile organic compounds (VOCs) at main roads, sidewalk bus stops, exclusive bus lane stops and gasoline stations in Taipei City, and the personal exposure levels of gasoline station workers. This study collected air samples from five main roads, four sidewalk bus stops, three exclusive bus lane stops, eight gasoline stations, and twenty-six gasoline station workers. Charcoal tubes were used to collect VOCs in air, and a GC/FID was used to analyze the concentrations of MTBE, n-hexane, benzene, toluene, ethylbenzene, and xylene.
The results showed the average concentrations of VOCs were the highest at gasoline stations, and decreased in sequence of main roads, exclusive bus lane stops, and sidewalk bus stops., the concentration were 75.8, 51.6, 113.4, 305.2, 45.0, 121.1 and 66.4μg/m3 for MTBE, n-hexane, benzene, toluene, ethylbenzene, m,p-xylene for o-xylene at main roads; respectively. These were 41.3、27.6、101.2、221.5、40.0、124.8 and 50.7 μg/m3 at exclusive bus lane stops, respectively. These were 42.1、16.7、71.8、115.7、23.7、40.2 and 17.3 μg/m3 at sidewalk bus stops, respectively.
Toluene was the major airborne VOCs, the concentrations were 305.2 at main roads and 166.6 μg/m3 at bus stops. The concentrations of VOCs in rush hours were higher in the afternoon than thos in the morning. The concentrations of VOCs at exclusive bus lane stops were significantly higher than that at sidewalk bus stops, and the former was several-fold than the latter.
At gasoline station, the airborn concentrations of MTBE, n-hexane, benzene, toluene, ethylbenzene, m,p-xylene and o-xylene was 685.3、212.9、203.7、577.5、86.1、234.5 and 93.9 μg/m3, respectively. The personal exposure of gas station workers was far belows the PEL of Taiwan OSHA regulation. The VOCs levels were not difference between private and public gas stations. Personal exposure levels of VOCs for gasoline station workers were significantly higher than that for ambient air.
|
|---|
