(VCCEP) Tier 1 Pilot Submission for BENZENE - Tera

Table 7.30: Average of Mean In-Vehicle Concentrations
Chang et al. (2000)
Benzene VCCEP Submission
March 2006
Study Description
Urban, Baltimore in Summer 1998
and Winter 1999
130
Mean In-Vehicle
Concentration
(µg/m 3 )
Batterman et al. (2002) Urban commute, Detroit, fall 1999 4.5
Fedoruk and Kerger (2003)
10.2
Urban communte, Los Angeles ,
1997
2.4
Average of study means 5.7
Due to various driving conditions under which a person may be exposed to in-vehicle
concentrations of benzene, mean concentrations best portray long-term exposure
concentrations. An average concentration was derived using the means of each of the three key
studies above. This average is used as the typical representative in-vehicle exposure
concentration and is considered to be an average of a high-end scenario, as it is representative
of urban exposures where traffic densities are highest.
Age-specific in-vehicle benzene exposures were quantified according to the following equation:
where:
C × ED × EF × ET × IR × ABSi × CF
ADD =
BW × AT
ADD = average daily dose (mg/kg-day)
C = concentration of benzene in vehicle air (µg/m 3 )
ED = exposure duration (years)
EF = exposure frequency (days/year)
ET = exposure time (hours/day)
CF = conversion factor (0.001 mg/µg)
ABSi = benzene inhalation absorption factor; 0.5 (unitless)
IR = inhalation rate (m 3 /hour)
BW = body weight (kg)
AT = averaging time (days)