Questions and Answers
What is dioxin?
Dioxin is the name of a family of chemical compounds that
are unintentional byproducts of certain industrial, non-industrial
and natural processes, usually involving combustion.
Different dioxin compounds have different toxicities.
Sometimes the term dioxin is also used to refer to TCDD, the
most well studied and most toxic form of dioxin. The
many different types of dioxin actually vary greatly in toxicity
-- some of them 10,000 times less toxic than TCDD.
Where does dioxin come from?
No one makes dioxin on purpose. Historically, incinerators, the manufacture of certain herbicides, and pulp and paper bleaching were among the largest industrial sources of dioxin. However, according to the Environmental Protection Agency (EPA) data, regulations and voluntary changes by industry have dramatically reduced dioxin releases from these industrial sources by 90 80% between 1987 and 2000 1995, with releases expected to drop by more than 90% within the next few years as new regulations are fully implemented.
How much dioxin am I exposed to?
Levels of dioxin in food -- which account for 95 percent
of our exposure to dioxin -- have been cut in half over the
past seven years. 
EPA has clearly emphasized that the U.S. food supply is among
the safest and most nutritious in the world. 
The World Health Organization sets its Tolerable Daily Intake
(TDI) at a range of 1 to 4 pg/kg/bw/day (picograms per kilogram
of body weight per day) for adults. A picogram is one-trillionth
of a gram. EPA estimates that the average U.S. adult intake
is 0.5 to 1 pg/kg/bw/day, clearly within, or below, that range.
People today are exposed to less dioxin than at any time
in the recent past. According to EPA, the amount of dioxin
in the average person's body has declined by more than 50%
since the late 1980s. 
Studies of levels of dioxin in human breast milk, blood and
fat tissue all show significant declines -- with decreases
ranging from 50 to 70 percent between 1980 and 1996. 
Average Body Levels of TCDD Are Down Dramatically
What are the possible health effects of exposure to dioxin?
Over the past 30 years, researchers have conducted many studies
to investigate the potential for adverse health effects from
accumulated levels of dioxin in people's bodies. According
to EPA, "currently there is no clear indication of increased
disease in the general population attributable to dioxin-like
Adverse health effects related to dioxin -- such as chloracne,
a severe skin condition -- have only been seen in people exposed
to extremely large quantities of dioxin. Extensive studies
of people exposed to relatively high levels of dioxin through
occupational exposures, accidents or military service do not
suggest that adverse effects to human health will occur at
the low levels in today's environment.
A large historical study of workers showed increased rates
of cancer, possibly from dioxin. However, those rates were
only seen in workers exposed for many years at amounts 100
to 10,000 times more than the general population. 
Exposure to other chemicals and cigarette smoking may also
have affected the results of the study, published in the May
1999 Journal of the National Cancer Institute.
What are companies and the government doing about dioxin?
Government and industry have worked together to reduce dioxin emissions dramatically since the 1970s. According to EPA data, as a result of these efforts, known industrial emissions in the United States have been ill be reduced by more than 90% since 1987. 
|Environmental Levels of Dioxins
and Furans Have Dropped Dramatically Over
the Past 25 Years 
Is dioxin from local companies creating a risk to my health?
Since 95% of human exposure to dioxin is through the diet,
exposure levels are generally more a function of what we eat
rather than where we live. Our food comes from a wide range
of sources throughout the world. Recent studies suggest that
the source of food items has little impact on dioxin levels
in human blood serum. 
Therefore, living near an industrial facility does not necessarily
mean that you are exposed to higher levels of dioxin than
the overall population.
Is there anything I can do to reduce my exposure to dioxin?
The EPA, FDA and other agencies note that since dioxin accumulates
in animal fats, following normal dietary recommendations for
a healthy, low-fat diet is the best way to reduce the potential
for dioxin exposure.
"The best strategy for lowering the risk of dioxins
while maintaining the benefits of a good diet, according to
the agencies," is to follow the recommendations in the
Dietary Guidelines to choose fish, lean meat, poultry, and
low or fat-free (skim) dairy products and to increase consumption
of fruits, vegetables and grain products..
Yet while recognizing peoples concern over dioxin exposure,
the Environmental Protection Agency, Food and Drug Administration,
and other federal agencies stress that the U.S. food supply
is among the safest and most nutritious in the world.
Neither agency recommends avoiding specific foods or taking
any special precautions to avoid dioxin exposure.
Why am I hearing about dioxins now?
EPAs Toxics Release Inventory was established in 1986
to track information on 650 chemical substances manufactured,
processed or used by U.S. production facilities each year.
EPA may add or remove chemicals to the TRI list based on their
toxicity. Dioxin was added to the TRI for reporting
purposes beginning in the year 2000.
 Assessment of
the Health Risk of Dioxins: Re-Evaluation of the Tolerable
Daily Intake (TDI), Executive Summary, World Health Organization,
 Questions and Answers About Dioxins, Interagency Working Group on Dioxin (representatives from the U.S. Environmental Protection Agency, Department of Health and Human Services, Department of Agriculture, Department of Veterans Affairs, Department of Commerce, Department of State, and the White House Office of Science and Technology Policy), October 2004.
 Draft Dioxin
Reassessment, Environmental Protection Agency, September
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Human Background Data for Germany, a 10-Year Experience,"
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Environmental Protection Agency, Office of Research and Development,
June 12, 2000.
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H. and Walczok, M., "Time Trends in Levels, Patterns
and Profiles for PCDD/PCDF in Sediment Cores of Lake Constance,"
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Ferrario, J., Byrne, C., Dupuy, A.E., Winters, D.L., Lorber,
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PCBs," Organohalogen Compounds 35: 29-32, 1998
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and Answers About Dioxins (see citation #2)