Exposure to volatile organic compounds while commuting in Taichung, Taiwan

The objective of this study was to compare volatile organic compounds (VOC) concentrations from six main roads in Taiwan's third largest city (Taichun g) and determine factors that affect VOC concentrations. Twenty-two VOC com pounds were determined on six roads using US E.P.A method TO-17, 0.2 g of C arbopack B was used as an adsorbant collector and thermal desorption and ga s chromatography/mass spectrometry (GC/MS) techniques were used to analyze VOCs, Results showed that car and motorcycle commuters were exposed to the highest VOC concentrations on Ta-Ya Road (2149 and 1343 mu g m(-3), respect ively). Except for Ta-Ya Road and Chung-Kang Road, motorcycle commuters wer e exposed to higher VOC concentrations than their driving counterparts. Fou r sampling periods were used in the study; exposure to VOC concentrations w as highest from 7:30 to 8:30 AM for motorcycle commuters (1515 mu g m(-3)) and from 5:00 to 6:00 AM for car commuters (1071 mu g m(-3)), while concent rations for all commuters were lowest from 2:00 to 3:00 P.M. Concentrations were negatively correlated to percentage of vacant lots along the road (PV L), yet not correlated to traffic volume. The ratios for toluene, benzene, xylene, and ethylbenzene (T : B: X: E) were similar for car commuters (5.5 : 2.1 : 2.6: 1.0) and motorcycle commuters (5.7 : 2.0: 2.6 : 1.0) which, co mbined with other published data, strongly suggest a vehicular source for h ydrocarbons in Taichung. Comparing these concentrations, Taichung was sligh tly lower than Taipei but 2-30 times higher than cities of other countries. It is concluded that the chronic exposure to high concentrations of hydroc arbons may pose a serious health risk to commuters in Taichung (C) 2000 Els evier Science Ltd. All rights reserved.