(VCCEP) Tier 1 Pilot Submission for BENZENE - Tera

Parental/Fetal Exposure
Occupational
Production/Processing
Manufacturing
Miscellaneous
Benzene VCCEP Submission
March 2006
Figure 7.1
Benzene Exposure Assessment
Personal
Outdoor
– Ambient (rural/urban)
– Industrial source area
Indoor
–Home
–Tobacco smoke
Fuels
–Automobile
–Small engine
Food/Water
97
Parental
Child
Personal
Breast milk Outdoor
– Ambient (rural/urban)
– Industrial source area
Indoor
– Home/school
– Tobacco smoke
Fuels
– Automobile
– Small engine
Food/Water
Benzene exposures to children and the prospective parents have been quantified by evaluating
the ambient or background benzene levels in a child’s/parent’s air (indoor and outdoor), diet,
and water as well as specific sources and microenvironments to which subpopulations of
children may be exposed. Available data indicate that all children are exposed to background
levels of benzene in the ambient air, water, and food supply as a result of releases from natural
sources, mobile sources, and the chain of commerce sources described in Section 5. In
addition to these ubiquitous sources, certain subpopulations of children may be exposed to
benzene in microenvironments depending on specific activities, such as use of equipment or
vehicles with internal combustion engines or living in a home where tobacco smoking occurs
(either used by parents or teenage children).
For most people, exposure to benzene is a daily occurrence. Inhalation is the primary and
dominant pathway of exposure, comprising the major component of individuals’ total benzene
exposure (WHO, 1993). Also, benzene has been shown to occur at low levels in a large
number of foods as the result of naturally occurring levels or possibly as a result of cooking
processes. Although dermal exposures to benzene are generally insignificant due to its high
volatility, this exposure route was also evaluated.
Benzene exposures vary by age. This age variation occurs because individuals interact with
different sources in different ways at different ages. Thus, a small child may be passively
exposed to benzene while riding in a car, whereas only an older child (teenager) or an adult will
have an exposure when actively refueling the car. Age variation also occurs because exposure-
related characteristics such as body weight, breathing rate, and diet vary with age. As such,
exposure scenarios have been developed for different age groups. Five age groups have been
chosen based on relevant activities upon which children spend substantial amounts of time