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This evening I will be discussing some of the findings of the Exposure to Mercury in West Virginia – Final Public Health report, WVDHHR’s response to the comments and the report conclusions and recommendations. 
Man’s activities put more mercury in the environment than would otherwise naturally occur.
Exposures to mercury can be reduced, but not eliminated, by restricting the emissions associated with man’s activities.
The report found:
The health effects from mercury exposures are of special concern for unborn babies and young children because it is a neurotoxin.  The public health report estimated possible health effects from exposure to children and adults, including women of child-bearing age and the effect on developing fetuses.
Exposures to mercury in air, drinking water, surface water, sediment, soil and food, including fish, were considered in the public health report.
Mercury spills were not included in this report because each incident is different and no general estimates of exposure can be made. 
Mercury spills are hazardous. 
Elemental mercury vaporizes at room temperature.
People have been exposed to hazardous amounts of mercury without being aware of their exposure because the vapors are colorless and odorless.
Spills must be cleaned up properly to avoid spreading contamination.
Once in the environment, mercury constantly cycles through the air, soil, water, and biota. It is slowly removed from the environment.
It is important to note that mercury can be changed to methylmercury in moist environments.
Methylmercury bioaccumulates in the food chain.
Methylmercury in fish is an important component of man’s exposure to mercury.
The public health report showed that 82-99% of exposure to mercury is from eating fish.
The concentration of mercury in fish and the amount of fish eaten are major factors for man’s exposure to mercury.
Mercury exposure in air is not at levels where breathing it might cause adverse health effects.  This held true even for people breathing air near a chlor-alkali plant.
The amount of mercury in the air becomes important in the methylation and bioaccumulation processes resulting in mercury accumulation in fish tissue.
Even though everyone is exposed to mercury, the amount of exposure in terms of milligrams of mercury per body weight per day is the important factor to determine if adverse health effects might occur.
People who do not eat fish are exposed to  mercury (other than from mercury spills) at levels unlikely to cause adverse health effects.
People who eat a lot of fish containing mercury may be at risk for subtle neurological effects. 
Various fish consumption scenarios are presented in Table 9 of the report indicating different number of meals and different mercury concentrations in fish tissue. Note that a 1 year old child would need to eat four ¼ pound fish meals per month containing 0.25 mg/kg or more to exceed the Minimal Risk Level. Similarly a woman of child bearing age would need to eat about 12 - ½ pound meals per month of fish containing 0.25 mg/kg mercury or more  to exceed the Minimal Risk Level.  Basses are the fish containing the most mercury in West Virginia and the average is 0.25 mg/kg.  Even when the MRL is exceeded, the exposures are not necessarily at levels where adverse health effects might occur.
Subtle neurological effects are apparent only with carefully-designed scientific study. These effects are detected using attention, fine-motor functioning, language, drawing, and verbal memory tests.
Fish are part of a balanced diet.  People can eat fish caught in West Virginia waters without experiencing harm from mercury exposures by following fish advisories.  People should follow national fish advisories for seafood and other fish.  This allows people to :
obtain the benefits from eating fish (such as the omega-3 fatty acids needed for proper neurological development) while
avoiding exposures to chemicals at levels that may affect their health.
Two studies noted in the report indicate the importance of omege-3 fatty acids on brain development.
Babies of mothers who have eaten too little omega-3-fatty acids have lower IQ scores.
In addition, mothers in the Seychelles Islands who ate the most fish had children who performed best when tested for neurological functioning, presumably due to the beneficial effects of omega-3-fatty acids on brain development.
Comments were received from two organizations and one individual before the end of the comment period.  Many of the comments received were suitable for WVDEP response.  Some comments were out of the scope of the Bureau’s authority, such as the request to eliminate coal preparation plants and coal-fired power plants.
We added several issues to the report in response to comments:
The report points out that plant-based sources of omega-3 available.  They are: flaxseed, canola oil, and walnuts.  The type of omega-3 fatty acids found in these foods are inefficiently metabolized to the essential omega-3 fatty acids found in fish. 
Rates of deep-ocean mercury removal are unknown because the global mercury cycle is not understood. 
The EPA estimates it may take 5 to 30 years after mercury emissions are changed for a steady-state to be reached in aquatic environments.
There are major differences between studies of mercury’s effects.  The Faroe Island study found adverse health effects at 1-2 ppm in the mother’s hair, while no effects were seen in the Seychelles Island study at an average of 6.8 ppm in the mother’s hair.  Differences between study design, the population studied, the type of mercury-containing fish eaten (people in the Faroe Islands eat pilot whales containing about 3 ppm mercury, 50% of which was methylmercury), the confounding of other contaminants (PCBs were in the fish eaten in the Faroe Islands). 
Some people have interpreted the Faroe Island study, where a measurable effect was observed in all people in the study, to mean that effects from mercury exposure can be measured for all exposures to mercury.  This is conclusion is incorrect.  As noted previously, other studies have shown no measurable effect for people with more exposure to mercury than in the Faroe Islands.
Six percent of women have mercury levels in their blood between 5.8 and 58 ug/L, within a factor of 10 of the level (58 ug/L) where adverse neurological effects have been observed.
About one in six (or 16%) women in the US have blood mercury levels equal to or greater than 3.5 ug/L.  This blood mercury level is lower than blood mercury levels corresponding to exposures equal to the Reference Dose, 5.8 ug/L.  Human studies have correlated maternal blood mercury levels to health effects occurring to their fetuses.  However, the researchers who believe this correlation has not been adequately considered are those who suspect babies are at “increased risk” of subtle neurological damage when maternal blood levels are 3.5 ug/L.  This opinion is not shared by all researchers. 
It is important to point out that the term “increased risk” is not the same as “measured adverse health effects.”
One comment was that rain in Chicago contained 42 times the mercury allowed by federal standards and 65 times the amount “safe” for humans in Detroit.  It is inappropriate to compare the mercury in rainfall to standards for mercury in Great Lakes and water that is safe for wildlife.  These standards are established to keep mercury in surface waters at amounts where mercury levels in fish and other wildlife should stay below certain amounts.  In fact, the amount of mercury in rain in these cities was much lower than the federal standard for mercury in drinking water. 
Based on the review of information cited in this report and the comments received WVDHHR concluded:
Reducing the amount of mercury in the environment will reduce the amount of mercury available to bioaccumulate in fish tissue.
However, there is inadequate data to allow WVDHHR to estimate the effect restricting mercury emissions in West Virginia might have on this state’s fish.
WVDHHR recommends the following
Even with this limited data, WVDEP should continue to reduce mercury emissions, due to potential adverse health effects from mercury exposure. WVDEP – Water and Waste Management should re-sample fish tissue for mercury residues, as planned, in watersheds where the most restrictive fish advisories occur. WVDNR and/or WVDEP should collect additional data about West Virginian’s fish consumption habits.
WVDHHR should increase the public’s awareness of fish advisories.
WVDHHR encourages the removal and proper disposal of mercury-containing materials from homes, schools, and workplaces.
West Virginian’s should eat fish as part of a well-balanced diet while following fish advisories to avoid harmful amounts of chemicals. People should be especially careful to follow fish advisories during a woman’s childbearing years and when infants and young children are in the household. West Virginian’s, particularly children, should be educated to avoid handling elemental mercury and what should be done should a spill occur. People who eat a substantial amount of fish or work with mercury should mention this to their dentist or other health care provider when mercury-containing dental amalgams are recommended. This is especially recommended for children 6-years-old or younger and women who are pregnant or nursing. In all cases, the choice not to use mercury amalgam should be made in consultation with a qualified dentist (and/or physician) and weighed against the risk of alternative practices or materials.
The report is available at these places. 
Thank you for your attention.