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 (Taichung) and determine factors that
affect VOC concentrations. Twenty-two VOC compounds were
determined on six roads using US E.P.A method TO-17, 0.2 g
of Carbopack B was used as an adsorbant collector and
thermal desorption and gas 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), respectively). Except for Ta-Ya Road and Chung-Kang
Road, motorcycle commuters were exposed to higher VOC
concentrations than their driving counterparts. Four
sampling periods were used in the study; exposure to VOC
concentrations was 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
concentrations 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 (PVL), 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, combined with other
published data, strongly suggest a vehicular source for
hydrocarbons in Taichung. Comparing these concentrations,
Taichung was slightly lower than Taipei but 2-30 times
higher than cities of other countries. It is concluded that
the chronic exposure to high concentrations of hydrocarbons
may pose a serious health risk to commuters in Taichung (C)
2000 Elsevier Science Ltd. All rights reserved.