(VCCEP) Tier 1 Pilot Submission for BENZENE - Tera

Table 7.44: Dermal Benzene Absorption Factors
% Dose Absorbed Exposure Species Reference
0.07% Neat Benzene Human Maibach 1980
0.08%
Benzene in solvent
(0.36%)
Rhesus Monkey Maibach and Anjo
1981
0.2%
Benzene in toluene
(0.5%)
Human Franz 1984
6.2%
Benzene
(0.5%)
in water Human Franz 1984
These studies indicate that a very low proportion of the applied volatile chemical is actually
absorbed by the skin.
In an occupational setting such as the petroleum processing or chemical manufacturing
industries, benzene or benzene containing products are handled in nearly 100% closed
systems. Thus, dermal exposure to the product is not common except under “upset” conditions,
where personal protective clothing including gloves and suits would be worn. Because of the
low probability for dermal contact with benzene in an occupational setting and the low dermal
absorption of benzene from a solvent-type mixture, dermal exposures for the prospective
parents have not been quantified.
Occupational Exposure Calculation
In evaluating the prospective parent’s occupational benzene exposure, the average of 0.11 ppm
(0.35 mg/m 3 ) and 95 th percentile value of 0.39 ppm (1.22 mg/m 3 ) from the ACC BTX Consortium
benzene survey have been used as typical and high-end exposure concentrations. It should be
noted that these values are below the current OSHA PEL of 1 ppm and action level of 0.5 ppm.
Exposures were quantified according to the following equation:
where:
Benzene VCCEP Submission
March 2006
C × ED × EF × ET × IR × ABSi
ADD =
BW × AT
ADD = average daily dose (mg/kg-day)
C = concentration (mg/m 3 )
ED = exposure duration (years)
EF = exposure frequency (days/year)
ET = exposure time (hours/day)
IR = inhalation rate (m 3 /hour)
ABSi = inhalation absorption factor (50%)
BW = body weight (kg)
AT = averaging time (days)
The typical and high-end occupational intakes for prospective parents are presented in Table
7.45.
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