Environmental Health Criteria 214

HUMAN EXPOSURE ASSESSMENT
beverages. Some hydrocarbons are known carcinogens or mutagens (e.g.,
benzene). Almost all cause eye irritation, coughing, drowsiness,
clumsiness and loss of alertness. Acute effects from industrial
exposures at the parts per million (µg/g) level include skin
reactions, dizziness and fainting. Sick building syndrome (SBS) and
multiple chemical sensitivity (MCS) have been associated with
relatively low (ng/g, parts per billion) concentrations of VOCs.
Between 1979 and 1987, the US EPA carried out the TEAM studies to
measure personal exposures of the general public to VOCs in several
geographic areas in the USA (Pellizzari et al., 1987; Wallace et al.,
1987a). About 20 target VOCs were included in the studies, which
involved about 750 people, representing 750 000 residents of the
areas. Each participant carried a personal air quality monitor
containing 1.5 g Tenax. A small battery-powered pump pulled about
20 litres of air across the sorbent over a 12-h period. Two
consecutive 12-h personal air samples were collected for each person.
Concurrent outdoor air samples were also collected in the
participants' backyards. In the 1987 studies, fixed indoor air
samplers were also installed in the living room of their homes.
The initial TEAM pilot study (Wallace et al., 1982) in Beaumont,
Texas and Chapel Hill, North Carolina indicated that personal
exposures to about a dozen VOCs exceeded outdoor air levels, even
though Beaumont has major oil producing, refining and storage
facilities. These findings were supported by a second pilot study in
Bayonne-Elizabeth, New Jersey (another major chemical manufacturing
and petroleum refining area) and Research Triangle Park, North
Carolina (Wallace et al., 1984a). A succeeding major study of 350
people in Bayonne-Elizabeth (Wallace et al., 1984b) and an additional
50 people in a non-industrial city and a rural area (Wallace et al.,
1987a) reinforced these findings (Table 39). A second major study in
Los Angeles and in Antioch-Pittsburgh, California (Wallace et al.,
1988), with a follow-up study in Los Angeles in 1987 (Wallace et al.,
1991a,b) added a number of VOCs to the list of target chemicals with
similar results (Table 40). Major findings of these TEAM studies
included the following:
* Personal exposures exceeded median outdoor air concentrations by
factors of 2-5 for nearly all of the 11 prevalent VOCs (Fig. 41).
The difference was even larger (factors of 10 or 29) when the
maximum values were compared. This is so despite the fact that most
of the outdoor samples were collected in areas with heavy industry
(New Jersey) or heavy traffic (Los Angeles).
* Major sources are consumer products (bathroom deodorizers, moth
repellents); personal activities (smoking, driving); and building
materials (paints and adhesives). In the USA, one chemical (carbon
tetrachloride) has been banned from consumer products and exposure
is thus limited to the global background of about 0.7 µg/m 3 .
* Traditional sources (automobiles, industry, petrochemical plants)
contributed only 20-25% of total exposure to most of the target
VOCs (Wallace, 1991a,b). No difference in exposure was noted for
persons living close to chemical manufacturing plants or petroleum
refineries.
The results of the VOC TEAM study encouraged investigators to
explore the causes for higher personal exposures. In a study designed
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