United (States
        Environmental-Protection
        Agency
ERA 540-K-99-003
OSWER 9285.7-30
December 1999
www.epa.gov
        Superfund  Risk

        Assessment—

        What it's all about
        And how you can help

We at EPA would like you to help us learn about the
health risks of the Superfund site in your commu-
nity. That's why we want to tell you about risk
assessment, a tool we use in deciding how to clean
up sites.
We hope that the more you know about risk assess-
ment, the more you can help us. And the more you
know, the more you'll understand the risks the site
may pose to you;and your family. You'll also see
that your interest in the site can improve cleanup.

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Risk Characterization
Risk Characterization, the final step of the process, sums it
all up. It reveals which chemicals are posing the risks and
what the health risks are. It also says how sure we are about
the results. Since some uncertainty about risk estimates is
unavoidable, we build in a large margin of safety to prevent
underestimation of the risks. These safeguards are intended
to protect the exposed public.

We now can use the risk assessment to develop a cleanup
plan that will make the site safe for current and future uses.
Here's how to get more
information
    Call the toll-free Superfund/RCRA Hotline at 1-800-
    424-9346 or the Community Involvement Coordinator
    in the EPA regional office for your state.
    Information is available on the Superfund home page
    (www.epa.gov/superfund) under the Community Tools
    and Technical Resources subheadings.

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Here's a brief review of
Superfund risk assessment

We study health risks based on what people do and are
likely to do on the site. Our goal is to protect everyone
who could come in contact with chemicals from the site
especially children, women of childbearing age, the
elderly, and others who may be at greatest risk.
                      Risk Assessment
                               Data
                     /\v Collection & Evaluation /\
                  , Exposure
                  Assessment
 Toxicity
Assessment
                                Risk
                            Characterization
We use a four-part
process to esti-
mate the chance
that contact with
chemicals from a
site will harm
people now or in
the future. This
process gives us
numbers that show
how great (or
small) the risks
may be. It also points to who is at risk, what is causing
the risk, and how sure we are about the numbers.

Data Collection and Evaluation

The first step of the pirocess is Data Collection and Evalu-
ation. We find out what has happened at and around the
site and where chemicals may have been left. We collect
samples of the soil, water, air, fish, garden vegetables,
and other things that might contain chemicals from the
site. From these samples, we try to find out what chemi-
cals are there and
how much. You can
help us find out
where chemicals
might be and how
                     You can help us find out—
                       Where chemicals are located
                       What people do on or near
                       the site

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they got there. For instance, you may have seen someone
dumping something or know about the history of the site.
This information helps us get better samples.
Exposure Assessment
                         People must come in contact with
                         chemicals from thesile to heatrisk
In the next step—Exposure Assessment—we use the data
collected in the first step to find out how much of each
chemical people rnay be exposed to. People must come in
contact with the chemicals to be at risk. The amount of
exposure depends a lot on how much of each chemical is
there, who might be exposed, and how they are exposed.
For instance, children might play in a polluted stream.
People might drink polluted well water or eat polluted
fish. You can tell us about these activities, which helps us
identify everyone who could be exposed. Your assistance
helps us estimate the highest exposure  anyone is likely to
receive from the site.
Toxicity Assessment
                         "The dose makes the poison" (Paracelsus,
                         Ii67) which means as dose rises, the
                         risk of harm rises
Toxicity Assessment is how we learn about which ill-
nesses or other health effects may be caused by exposure
to chemicals. It also says at what dose harmful health
effects will occur. This is the same as saying how much
of each chemical it takes to cause harm. The higher the
dose, the more likely a; chemical will cause harm.

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