| Q: |
Why has Illinois issued a statewide methylmercury advisory?
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| A: |
The
Illinois Fish Contaminant Monitoring Program (IFCMP)* has issued a statewide
advisory for predator fish in Illinois waters due to methylmercury. The change
is based on recent studies that have shown adverse effects to the developing
nervous system of fetuses that could result in lower IQ, abnormal muscle tone
and slowed motor function. The advisory has been established to protect the
most sensitive populations: pregnant and nursing women, fetuses, women of
childbearing age and children younger than 15 years of age. *IFCMP includes staff from the departments of
Agriculture, Natural Resources and Public Health and the Illinois Environmental
Protection Agency. |
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| Q: |
Why is there a special methylmercury advisory for these populations?
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| A: |
Pregnant and nursing women, women of childbearing age and children
younger than 15 years of age are at high risk for adverse health effects
because the developing nervous systems of infants and children are more
sensitive. |
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| Q: |
Has the concentration of mercury increased in Illinois predator sport
fish? |
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| A: |
No.
Methylmercury levels detected in predator sport fish have remained about the
same. The advisory has been issued based on the results of recent scientific
studies indicating that methylmercury is more toxic than previously thought.
Based on the study results, the guidelines that are used to establish the
Illinois fish advisories have been lowered for methylmercury. |
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| Q: |
Why is the statewide methylmercury advisory only for predator
species? |
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| A: |
Mercury stays in the environment for a long time. Small organisms
absorb mercury from water and sediment; these organisms then are eaten by
smaller fish. Predator fish eat the smaller fish and methylmercury is
accumulated up the food chain. Larger fish have the highest amounts of
methylmercury stored in their bodies. Predator species for Illinois include
all species of black bass (largemouth, smallmouth and spotted), striped bass,
white bass, hybrid striped bass, walleye, sauger, saugeye, flathead catfish,
muskellunge and northern pike. |
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| Q: |
Is mercury stored in the human body for long periods of time?
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| A: |
When
methylmercury is ingested, most of it is absorbed through the gastrointestinal
tract into the bloodstream where it is rapidly carried to other parts of the
body. It takes about 70 days for half of the mercury that has entered the body
to be removed. The remaining mercury is slowly removed from the body over
several months, mainly in feces. |
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| Q: |
How does methylmercury get into bodies of water in Illinois?
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| A: |
Mercury is a metal that occurs naturally in small amounts in the
environment. It also comes from burning coal or trash and from industry.
Mercury gets into lakes and rivers in several ways, including rain and runoff.
When conditions are right in the water, certain kinds of bacteria change
metallic mercury into the more toxic methylmercury. Methylmercury is stored in
the muscle of fish, the part of the fish people eat. |
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| Q: |
What are the potential health effects for people who eat fish
contaminated with methylmercury? |
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| A: |
A:
The developing nervous systems of fetuses and children could be damaged if
exposed to even small amounts of methylmercury. At high doses, methylmercury
can affect the central nervous system (causing such health problems as memory
loss and slurred speech) and can cause kidney damage and failure, and
gastrointestinal damage. The possible health effects depend on how much
methylmercury is stored in the fish and how much fish is eaten over a period of
time. Based on the amounts of methylmercury detected in predator sport fish in
Illinois, it is unlikely that people would experience adverse health effects
associated with exposure to high doses. |
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| Q: |
What about the fish I buy in the grocery store? Should I be concerned
that they may be contaminated with mercury? |
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| A: |
Fish
such as shark, swordfish, king mackerel and tilefish contain high levels of
methylmercury. The U.S. Food and Drug Administration (FDA) is advising pregnant
women, women of childbearing age and children not to eat these fish. The FDA
advisory acknowledges that seafood can be an important part of a balanced diet
for pregnant women and women of childbearing age. The FDA advises these women
to select a variety of other kinds of fish, such as shellfish, canned fish
(including tuna), smaller ocean fish or farm-raised fish. These women
can safely eat 12 ounces per week of cooked fish. A typical serving of fish is
from 3 ounces to 6 ounces. |
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| Q: |
Should I be concerned about children swimming in bodies of water in
Illinois because of mercury contamination? |
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| A: |
No.
Contact with, or the accidental swallowing of, the water will result in minimal
exposure to methylmercury. |
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| Q: |
Why is there a special mercury advisory for some bodies of water in
the state? |
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| A: |
Laboratory results from predator sport fish in some bodies of water
have shown more
contamination than what has typically been found in other bodies of water.
Based on these higher concentrations of methylmercury, a more restrictive
advisory is necessary to protect public health. |
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| Q: |
What is being done to reduce the amount of mercury entering the
environment from man-made sources? |
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| A: |
There
are several actions being taken at the national, regional, state and local
levels. |
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- At the national level, the U.S. Environmental
Protection Agency (USEPA) is developing standards for mercury-emitting air
pollution sources that should be released soon. USEPA also is working on
regulations on air pollution controls to limit the amount of mercury emitted
from coal-burning power plants, which have been identified as significant
sources of airborne mercury.
- At the regional level, some of the approaches
for voluntary reductions in mercury releases developed by the U.S.-Canadian
Binational Toxics Strategy group are being implemented in the Great Lakes
basin.
- At the state level, the Illinois Environmental
Protection Agency (IEPA) is researching sources of mercury release to the air
and identifying opportunities for mercury reductions through regulations and
air pollution permits. IEPA also has sponsored several bills to reduce or eliminate mercury in consumer products.
- At the local level, there are a few
fluorescent lamp recycling programs. A list can be found at www.epa.state.il.us/land/citizen-involvement/recycling/index.html.
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