(VCCEP) Tier 1 Pilot Submission for BENZENE - Tera

Table 7.12: Summary of Benzene Measurements from Attached Garage Studies in Alaska
Study Location
Isbell et al., 1999
Schalapia and
Morris, (1998)
Benzene VCCEP Submission
March 2006
Number of
Small Engines
in Garage
Benzene
Concentration
(µg/m 3 )
Home 1 0 3.8
Home 2 4 230.4
Home 3 0 1.3
Home 4 2 109.4
Home 5 0 16.3
Home 6 0 17
Home 7 0 35.8
Home 8 1 28.2
91 homes with attached
garages
Morris, (2004) 46 single family homes with
attached garages
Study Mean: 55.3
Min = 0.64
Max = 1,161
Arithmetic mean
= 71.5
Geometric mean
= 21
Mean = 24.2
Median = 16.4
Max = 113
7.2.1.6 Daily Doses for Ambient Indoor Air
115
Comments
Fairbanks, AK, July 1998. Benzene
content in gasoline 3 - 4%. Information
about automobiles parked in garages not
given. Reported benzene concentrations
were strongly correlated to the number of
small engines (snowmobiles, snow
blowers, chainsaws, etc.) stored in the
garage. Location(s) sampled within the
home were not discussed.
Anchorage, AK, 1994 – 1996. Benzene
content in gasoline from 2 major
distributors in Anchorage ranged from 2.2
– 4.5%. Homes included single and multifamily
structures, and approximately 15%
of the homes were considered smoking
households. No significant difference was
found between homes with at least one
smoker and those without. Benzene
higher in homes with cars parked in
garages, with forced air heating systems,
a living area above the garage, and a fuel
container opened within 3 days of indoor
air testing.
Anchorage, AK, 2003 – 2004. Benzene
content in gasoline described as 3.9% in
presentation, though source is unclear.
AAM survey indicates benzene levels in
Alaskan gasoline ranged from 3.3 - 3.8 in
2003 and 2.1 – 3.5% in 2004. Homes
included single family homes with
attached garages that were selected as
representative based on age of home and
square footage. Air exchange rates were
measured for each home and the garage.
No significant association was shown
between the benzene level in the garage
and the number of vehicles parked in the
garage, the age of vehicles in the garage,
and the number of trips originating from
the garage.
Age-specific average daily doses were calculated for in-home exposures using 2.5 µg/m 3 as the
typical in-home exposure concentration (average of the median values presented on Table
7.10), and 11.5 µg/m 3 as the high-end exposure concentration from the attached garage study
of Adgate et al. (2004b). Exposures were also quantified for residents in Alaska using the mean
concentration of 24.2 µg/m 3 from Morris (2004). Exposure was quantified according to the
following equation:
C × ED × EF × ET × IR × ABSi × CF
ADD =
BW × AT