Environmental Health Criteria 214

HUMAN EXPOSURE ASSESSMENT
1984; Akland et al., 1985; Johnson et al., 1986). About 800 people in
DC and 450 in Denver were monitored for 24 h (48 h in Denver) using
electrochemical carbon monoxide monitors with specially designed data
loggers. The data loggers were capable of sampling the current from
the monitor about 4 times a second. They were equipped with buttons
that the subject could press when one activity ended and the next
began; at that point, the logger would average all preceding values
from the time the activity began. (There was also an automatic
averaging every hour.) The result was an extraordinarily rich
database, with approximately 1200 people averaging 40 activities per
day, each with an associated average carbon monoxide level. At the end
of the monitoring period, each subject provided a breath sample. Major
findings of the study included the following:
* Commuters had the highest exposures to carbon monoxide in general,
averaging up to 13 µg/g. Parking garages had the highest carbon
monoxide levels of any microenvironment, with churches and schools
among the lowest.
* The main indoor sources of carbon monoxide were gas stoves and
cigarettes. Gas stoves increased levels by about 2.5 µg/g when
being used; homes with smokers had increases of about 1.5 µg/g on
average.
http://www.inchem.org/documents/ehc/ehc/ehc214.htm
Page 209 of 284
6/1/2007