Studied in 1991 were employees of the U.S. Army working
in Kuwait City (about 20 kilometers from burning oil wells) in May (Group
I) and firefighters and medical personnel who worked at the sites of burning
wells in October (Group II). Participants completed questionnaires and
provided blood samples right after the end of a typical work day. Blood
samples from participants in a U.S. health survey were also collected
(US Group). Blood was analyzed for concentrations of 6 volatile organic
compounds (VOCs) (benzene, ethylbenzene, m-/p-xylene, o-xylene, styrene,
and toluene) via mass spectrometry. Compared to the US Group, median VOC
concentrations were higher in Group II and lower in Group I. Among the
cigarette smokers in Group II, concentrations of benzene and toluene were
significantly higher than among non-smokers. The authors conclude that
exposure to VOCs was higher near the burning oil wells than in Kuwait
City. Although this study did not measure air concentrations of VOCs,
the authors cite data from other investigators who measured higher concentrations
near the oil wells. The authors note that the half-life of VOCs in blood
is less than 4 hours, so measured levels reflect exposures that occurred
over only the past one day. Limitations of the study: study subjects may
not be representative of all Americans in Kuwait at the time of the oil
fires; study subjects were volunteers, a possible source of selection
bias; the two groups were sampled at different times in 1991; the samples
were taken at one point in time and results can not be extrapolated to
describe long term exposure levels for persons in Kuwait; the results
can not be used to assess potential health effects from exposure to VOCs
in Kuwait. |