"Benzene Emissions and Exposure - Targeting Sources for the Greatest Benefit"
"Benzene Emissions and Exposure - Targeting Sources for the Greatest Benefit"
ABSTRACT
Issuance of recent air quality construction and operation permits
for iron foundries in Wisconsin has generated public concern over the
air
quality impacts of trace benzene emissions. These emissions are a
product of incomplete combustion which occurs when molten iron comes in
contact with organic binders in the sand core and molds. In
Wisconsin,
approval of industrial benzene emissions requires control by use of
Best
Available Control Technology (BACT) and a demonstration that the
residual
emissions are not injurious to humans or the environment. The
results
of the BACT determination and of the air quality impact analysis for
benzene
are presented at a public hearing prior to permit issuance by the state
agency. To better inform the general public about foundry benzene
emissions, public informational materials were developed by Wisconsin
foundries.
These compare of foundry benzene emissions with other sources of
benzene
exposure. Emissions and exposure data were taken from the permit
support documents for foundries, USEPA National Air Toxics Assessment
and
existing literature. Current benzene emission inventories
indicate
that less than one percent of benzene emissions result from industrial
operations. The remainder is generated by area and mobile
sources.
The predicted health risks due to foundry benzene emissions are much
less
than background concentrations and other common sources of risk.
These comparisons place industrial emissions and impacts in context
with
other more familiar activities. If they were more widely
publicized,
members of the general public would be able to make more informed
decisions
about the risk posed by local industries. These comparisons also
suggest that everyone will benefit if the focus of benzene control
strategies
includes non-industrial as well as industrial sources.