Exposure to volatile organic compounds: Comparison among different transportation modes

• Published in: Atmospheric environment (1994) 2014-09, Vol.94, p.53-62
• Main Authors: Do, Duc Hoai, Van Langenhove, Herman, Chigbo, Stephen Izuchukwu, Amare, Abebech Nuguse, Demeestere, Kristof, Walgraeve, Christophe
• Format: Article
• Language: English
• Subjects: Air. Soil. Water. Waste. Feeding; Applied sciences; Atmospheric pollution; Belgium; Bicycle; Biological and medical sciences; Car; Commuter exposure; Environment. Living conditions; Exact sciences and technology; Ghent; Inhalation dose; Medical sciences; Pollution; Pollution sources. Measurement results; Public health. Hygiene; Public health. Hygiene-occupational medicine; Tram; Transports; VOC
• ISSN: 1352-2310; 1873-2844
• DOI: 10.1016/j.atmosenv.2014.05.019

The increasing trend of promoting public transportation (bus tram, metro, train) and more environmental friendly and sustainable non fossil-fuel alternatives (walking, cycling etc) as substitutes for auto vehicles brings forward new questions with regard to pollutant levels to which commuters are exposed. In this study, three transportation modes (tram, auto vehicle and bicycle) are studied and concentration levels of 84 volatile organic compounds (VOCs) (hydrocarbons, aromatic hydrocarbons, oxygen containing hydrocarbons, terpenes and halogenated compounds) are measured along a route in the city of Ghent, Belgium. The concentration levels are obtained by active sampling on Tenax TA sorbent tubes followed by thermal desorption gas chromatography mass spectrometry (TD-GC-MS) using deuterated toluene as an internal standard. The median total VOC concentrations for the tram mode (33 μg/m³) is 1.7 times higher than that of the bicycle mode (20 μg/m³) and 1.5 times higher than for the car mode (22 μg/m³). It is found that aromatic hydrocarbons account for a significant proportion in the total VOCs concentration (TVOCs) being as high as 41–57%, 59–72% and 58–72% for the tram, car and bicycle respectively. In all transportation modes, there was a high (r > 0.6) degree of correlation between BTEX compounds, isopropylbenzene, n-propylbenzene, 1,3,5-trimethylbenzene and 1,2,4-trimethylbenzene. When comparing time weighed average concentrations along a fixed route in Ghent, it is found that commuters using the tram mode experience the highest TVOCs concentration levels. However, next to the concentration level to which commuters are exposed, the physical activity level involving the mode of transportation is important to assess the exposure to toxic VOCs. It is proven that the commuter using a bicycle (4.3 ± 1.5 μg) inhales seven and nine times more benzene compared to the commuter using the car and tram respectively, when the same route is followed. •Comparison among three modes of transportation (tram, bike, car) in Ghent, Belgium.•The aromatic compounds are the most abundant class (41–72% of the TVOC).•TVOCs concentration levels observed in the tram are the highest.•The inhaled dose for benzene for the commuter taking the bicycle is the highest.