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Sections:
Contaminants and Health Risks
Implementing and Determining Solutions
Information about BPH, DNR and DEP Collaboration
Advisory Information/Fish Preparation
Contaminants and Health Risks
(click here for print version)
Contaminants
-- Fish and
other aquatic organisms are indicators of the environmental health of our
waterways. Certain chemicals tend to accumulate in fish. The chemicals
currently of greatest concern in
West Virginia
are dioxin, polychlorinated biphenyls (PCBs) and mercury. The West
Virginia Bureau for Public Health (BPH) also encourages anglers and
consumers to review the United States Environmental
Protection Agency's (EPA) and Food and Drug Administration's (FDA)
recent national revised advisory notification issued in 2004 at,
http://www.epa.gov/waterscience/fishadvice/advice.html which warns pregnant women, women of childbearing age, nursing mothers,
and children about the health concerns of consuming fish that may be
contaminated with mercury.
According to the
EPA, the current major source of dioxins is from incineration. Dioxins are
produced in small quantities during the combustion of fossil fuels, wood, and
municipal and industrial waste. Bleaching processes used in pulp and paper
production also produce dioxins, and they occur as contaminants during the
production of some chlorinated organic chemicals. Dioxins have been detected in
soil, surface water, sediment, plants, and animal tissue in all regions of earth
and are highly persistent in the environment. Dioxins in surface waters and
sediments are accumulated by aquatic organisms and bioaccumulated through the
aquatic food chain.
Past industrial
activities in the lower Kanawha Valley, especially near the city of
Nitro,
West Virginia, have resulted in several dioxin-contaminated sites. Dioxin likely
originated with the production of industrial solvents and the herbicide 2,4,5-T
at facilities in and around Nitro. Disposal practices earlier in the 20th
century-- including burial of drums, dumping of dioxin-contaminated liquid
wastes, and incineration of dioxin-contaminated material-- spread dioxin
throughout the Nitro area. Areas downstream of Nitro likely became contaminated
through the release and transport of dioxin into the Kanawha River and its
tributaries. The Kanawha River and two of its tributaries, the Pocatalico River
and Armour Creek, have been the focus of a total maximum daily load (TMDL) study
and preliminary federal Superfund investigations to determine the location and
extent of the dioxin sources.
In
March 2004, EPA entered into an administrative order to conduct an Engineering
Evaluation/Cost Analysis to study dioxin-contaminated sediment in the
Kanawha River.
The purpose of this is to evaluate response alternatives that would protect
public health, welfare, and the environment and to provide sufficient
information for EPA to determine the necessity, feasibility, and
effectiveness of particular non-time critical removal actions. Although the
manufacture of PCBs has been banned since 1979, these compounds were used
extensively for heat transfer agents, lubricants, plasticizers, and
waterproofing. Due to indiscriminate disposal and atmospheric transport, PCB
residues are found worldwide and continue to persist in the environment.
Mercury is
a naturally occurring metal found in the environment. Inorganic mercury may
enter the air through burning of fossil fuels, mining, and waste or industrial
emissions. In freshwater bodies, small organisms convert inorganic mercury to
the organic form, methylmercury, which enters the aquatic food chain by binding
with particles and sediment eaten by the fish. Large fish will accumulate
mercury when they eat smaller mercury-contaminated fish. Fish eliminate mercury
at a very slow rate; therefore, mercury tends to accumulate in their tissues and
organs. Mercury has been detected in most fish species sampled from freshwater
bodies in West Virginia and other states. However, the range is quite broad and
varies by water body and by species of fish. Sources of mercury emissions in
West Virginia have been identified and are reported in "Atmospheric Mercury
Emissions in West Virginia"(Updegrave, 2004). This report is available at
http://www.wvdep.org/Docs/10805_Becky%20Report.pdf.
Selenium is a
naturally occurring mineral that is widely distributed in most rocks and soils.
It is a component of pigments in plastics and paints. Selenium is also used in
the preparation of pharmaceuticals, pesticides and rubber. Selenium can be
released into the environment during the combustion of fossil fuels and when
metals are smelted. It is present in the leachate from coal fly ash disposal
areas. In West Virginia selenium has been found downstream of large-scale earth
disturbance activities.
Health
Risks -- Health risks are categorized as acute (immediate) or chronic
(long-term). There are no known acute health risks at low levels of contaminants
in fish tissue. However, there are chronic concerns. The fish-related
carcinogenic risks are greatest for anglers who frequently consume large
quantities of fish from contaminated waters. One useful way of placing these
advisories into broader perspective is to consider how the health risks
associated with eating contaminated fish compares to other everyday risks.
Cancer will affect about one in every three people in
West Virginia,
primarily due to tobacco use, poor diet and heredity factors. The risk of
contracting cancer as a result of PCBs, dioxins and other contaminants in fish
is much lower. As a policy, the Bureau for Public Health (BPH), Division of
Natural Resources (DNR) and Department of Environmental Protection (DEP) seek to
reduce risks associated with chemical exposure to no more than 1 in 10,000.
Because the current risks associated with specific species located within the
advisory areas exceed this goal, BPH, DNR and DEP are recommending that the
public reduce or eliminate consumption of contaminated fish.
Your risk of
cancer from eating contaminated fish cannot be predicted with certainty.
Exposure to contaminants in the fish you eat may not increase your cancer risk
at all. Children, women of childbearing age and people who frequently eat fish
are particularly susceptible to contaminants that build up in the body over
time. If you follow this advisory over your lifetime, you will minimize your
exposure and reduce whatever cancer risk is associated with those contaminants.
Long lasting
contaminants such as PCBs and dioxin build up in your body over time. It may
take months or years of frequently eating contaminated fish to build up amounts
that are a health concern. Health problems which may result from the
contaminants found in fish range from small barely detectable health changes to
cancer. Adults are less likely to have health problems at the low levels that
affect children.
People who
consume moderate amounts of fish in a varied diet typically are not at risk of
exposure to high levels of mercury. However, mercury may cause damage to the
nervous system of an unborn child. Pregnant women who have high amounts of
mercury in their body pass some directly to the fetus. Because the effect
mercury has on the nervous system is so well documented and because the
developing fetus is highly sensitive, the BPH recommends that, pregnant, women
of child bearing age, nursing mothers, and children follow both the West
Virginia Sport Fish advisory recommendations and the USEPA/FDA recommendations
on restaurant and grocery-acquired fish.
Selenium in an
essential nutrient and is frequently a component of multiple-vitamin
supplements. Excessive exposure to selenium may disrupt endocrine function and
growth hormones and cause dermatologic effects, such as hair and nail loss.
Understanding
fish consumption guidelines will help you make informed choices. It is important
to consider both meal frequency and portions sizes when consuming sport-caught
fish. If a fish is listed in the “one meal per month” category, refer to the
“Meal Size” table to determine the appropriate meal size for you or your child.
If the guidelines are followed, eating such fish no more often than one meal per
month should cause no significant health risks. The fish consumption advice, if
followed for a 30 - year period has a health impairment risk factor of 1 in
10,000. Since most people would not eat that much fish from public waters, it
is easy to see that these guidelines are very conservative.
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Implementing and Determining
Solutions
Informing the public -- The advisories are intended to provide the public with
information to make an informed decision regarding fish consumption. The
information will be distributed to the media and through local and state
health departments, DNR's fishing regulations and DEP regional offices.
Phone numbers and website locations for the three agencies will be
included on all materials so that the public can easily obtain answers to
their questions.
Reducing
pollution in our waterways --
West Virginia's
water quality management goal is to reduce these advisories by eliminating the
sources of pollution. DEP is aggressively working toward this goal through the
state hazardous waste management and environmental remediation programs and
through the federal Superfund program, the non-point source pollution program,
control of combined sewer overflows, the sediment and storm water control
program, and other activities. A study performed by the USEPA in 2000 (Dioxin
TMDL Development for Kanawha River, Pocatalico River, and Armour Creek, West
Virginia, September 14, 2000) indicated that a 99 percent reduction in existing
load from ground water sources and a 92 percent reduction in load from soils
during wet weather events would be necessary for the Kanawha River to be in
compliance with the state’s dioxin water quality standard. As mentioned
previously, the EPA is continuing to assess the extent and magnitude of
dioxin contamination in the Nitro area.
Additional fish contamination monitoring -- Fish contamination is a measure of
environmental health as well as a potential source of human illness. BPH, DNR,
and DEP are striving to improve the understanding of fish contamination
throughout
West Virginia.
In 2001, DEP secured a grant from the USEPA to conduct a two year statewide
evaluation of fish for PCB and mercury contaminants.
The DEP, DNR, BPH and the
West Virginia University/US Geological Cooperative Fish and Wildlife Research
Unit conducted this research. The study was finalized in 2004 and supplied the
basis for the 2005 Fish Consumption Advisories. Unfortunately, funding for
continuing tissue collection and analysis remains an issue, especially if the
program is to include dioxin monitoring. Dioxin sampling is prohibitively
expensive, and unless substantial financial resources are located, no further
testing for dioxin is scheduled or anticipated.
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Information about BPH, DNR
and DEP Collaboration
Information about fish contamination in West Virginia has been collected
since the late 1970s. Beginning in the 1980s, the Division of Natural
Resources and the Bureau for Public Health were issuing advisories and
posting notices in the area of affected waters.
Starting in 1992, the DNR, BPH, and DEP maintained an informal technical work group composed of
staff from each agency to assess, manage, and consistently communicate to
the public issues related to fish contamination. Through Governor
Underwood's
September 2000 Executive Order,
however, the agencies started a more formalized collaborative process
through an
interagency agreement (PDF
format) to guide activities associated with fish consumption advisories.
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Advisory
Information/Preparation Advice
West Virginia
has implemented risk-based principles to determine whether fish consumption
advisories are needed. These advisories are intended to inform and educate the
public so they can make decisions about eating fish caught in West Virginia
waters. The advisories inform the public about elevated levels of chemicals in
fish while still allowing people an opportunity to enjoy recreational fishing
and appropriate consumption. The risk-based approach estimates the probability
of adverse health effects. The principles consider information on:
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the concentration of
contaminants in the edible portion of the fish;
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the type of adverse health
effects associated with the detected contaminants;
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the relationship between the
dose (a ratio between the contaminant concentration, human body weight and
time) and the human health response; and
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the expected exposure of the
contaminants to the human population through fish consumption.
The information
we gather by monitoring contamination in fish results in a statement on the
health risk posed to the angler and particularly high-risk groups such as women
of childbearing age and children. Advisories include advice on proper fish
preparation to reduce and minimize risk. The intent is that fish consumers
should be given information needed to evaluate risk.
Evaluating
health risks of eating contaminated fish should be balanced with the knowledge
that fish are nutritious and good to eat. When properly prepared, fish provide
numerous health benefits. The American Heart Association recommends eating two
to three fish meals each week. The benefits of eating fish include:
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Fish offer high-quality
protein with fewer calories than a similar-sized portion of meat. For example,
both catfish and ground beef are about 18 percent protein. But for an eight
ounce meal, the catfish has about 232 calories while the ground beef has about
640 calories.
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Fish are low in sodium and
are a good source of potassium, vitamins and other minerals.
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Fish are generally low in
cholesterol and saturated fats, which have been associated with heart disease.
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While the health benefits of
fish are still being studied, much of the current research is focused on
various kinds of beneficial fats in fish, particularly the kind called omega-3
fatty acids found in some fish and fish oils. Some studies have indicated that
these fatty acids have favorable effects on health conditions such as
hardening of the arteries and high cholesterol.
Preparation Advice --
You can further reduce your exposure to contaminants by following
these recommendations:
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Eat smaller fish. As a
general rule, larger, older fish may be more contaminated than smaller,
younger fish.
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Vary the kind of fish you
eat. Trout and sunfish, such as bluegills, eat insects and other aquatic life
that are less likely to contain high levels of contaminants. Top predators
like bass and walleyes may have higher levels of contaminants. If you eat
these species, eat the smaller fish to minimize your exposure.
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Clean and cook fish
properly. How you clean and cook fish can reduce the level of contaminants by
as much as half in some fish. Some contaminants concentrate in the fatty
tissues and internal organs of fish. Filleting, removing the skin and internal
organs, and trimming the fat along the back, side, and belly of the fish
reduces the contaminants you eat. While cooking does not destroy contaminants,
heat from cooking melts some of the fat and allows some of the contaminated
fat to drain away. Broil, grill, or bake the trimmed, skinned fish on a rack
so that the fat drips away. Deep-fat frying removes some of the contaminants,
but you should discard the oil after you cook the fish. Pan frying does not
remove much of the contaminants.
Graphic
reprinted with permission from the Georgia Department of Natural Resources
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