Study to examine impact of mercury in Grand Lake fish

By Wally Kennedy

wkennedy@joplinglobe.com

MIAMI, Okla. — Within three years or so, people who eat fish from Grand Lake will know how much mercury may be on their dinner plates, too, following a $1 million study.

Mercury is a neurotoxin that can hurt the brain, spinal cord, kidneys, lungs and liver. It is especially dangerous to fetal development.

“We might find out that you can eat fish and be just fine,” said Bob Lynch, with the University of Oklahoma Health Sciences Center, a member of the study team. “But it might not be fine. It could well come out, from what we already know, that certain fish consumed in certain quantities are a problem,’’ he said.

“We hope we can tell people it is OK. But we don’t know that. That’s the point of this research,’’ he said.

What is known, said Earl Hatley, an environmental activist with the LEAD Agency in Miami, another member of the study team, is that airborne mercury from coal-fired power plants is falling into the lake and its watershed. Grand Lake’s watershed includes the Spring and Elk rivers in Missouri, and the Neosho River in Kansas. Tar Creek, a source of heavy metals from the Picher Mining Field, is part of the watershed, too. The water column in the lake also is affected by nutrient runoff and bacterial loading.

When mercury moves through the environment, it goes through a series of complex changes, Hatley said.

“It’s the conversion of mercury into methyl mercury,’’ he said. “It’s the organic form of mercury. For that to happen, you have to have nutrients and bacteria.’’

Methyl mercury enters the food chain and accumulates most readily in fish at the top of the food chain, including all species of bass, walleye, saugeye and flathead catfish. It enters the food chain via algae, which is consumed by small fish, which, in turn, are eaten by bigger fish.

Widespread

Scientists have long known that mercury is present in fish. In fact, just last fall, the Environmental Protection Agency released a comprehensive study on mercury and other pollutants in fish sampled from more than 500 lakes nationwide. Mercury concentrations in fish fillets exceeded the EPA’s guidelines in 49 percent of the samples.

The EPA already recommends that “sensitive populations” — pregnant women, women who could become pregnant, nursing mothers and children younger than the age of 13 — eat no more than one serving of fish per week caught in any lake or river in the country because of mercury.

A report released in January 2009 by the Oklahoma Department of Environmental Quality also found that some of Oklahoma’s southeastern lakes have high levels of mercury. Fish-consumption advisories specific to those lakes have been issued.

The new study wants to go beyond that, however.

“We also know that the ODEQ has issued a fish-consumption advisory for mercury involving all water bodies in the state. That includes farm ponds,’’ Hatley said. “We know there is mercury in the water and we know there is mercury in the fish. What we don’t know is how that is affecting the people who eat the fish.’’

Another partner in the research is the Harvard School of Public Health. The plan is to find 150 volunteers who eat fish from the lake and have them fill out food frequency questionnaires four times per year. The questions will be about the types and frequency of fish eaten. The participants also will provide a hair sample, which will be measured for mercury by researchers at Harvard.

“Hair is often used as a biomarker of mercury exposure,’’ Hatley said. “Analyzing the amount of mercury in a person’s hair will provide an indication of the amount of mercury in his or her diet.’’

Participants will receive the results of their mercury measurements, along with general information about mercury to help interpret the results.

Funding research

The research team is being funded by a grant of $250,000 annually over four years by the National Institute of Environmental Health Sciences, Hatley said.

Lynch said, “What we want is a more specific idea about the situation here. After we have done this, people in other places with similar conditions can compare. We will know more about how mercury moves in the atmosphere and is transformed in the environment.

“The data will be useful in that it will not be site specific. The sampling techniques and the recruiting of people will give us a statistically accurate picture of what is going on here. It would be applicable to any place similar to Grand Lake,’’ he added.

The study will examine all types of fish — some 20 species — commonly caught and consumed from Grand Lake and its tributaries. It will include not only predator fish, which are expected to have higher levels of mercury, but also fish that are lower on the food chain. Several samples will be taken from a single species to determine how much a mercury level might vary within a species.

“A person might get as much exposure from eating a certain species of fish that is not a predator fish,’’ Lynch said. “What we know about what’s in the fish is fairly limited.’’

The data gathering will take about a year. Toward the end of the third year, the data will be analyzed and released. The volunteers, he said, will get back data about their exposure level within two to three months.

Unregulated

Ken Midkiff, with the Sierra Club of Missouri, said much of the mercury in fish comes from coal-fired power plants.

“Further compounding what we put into the air is the mercury contamination coming from China and other parts of the world,’’ he said. “The state of Missouri has issued an advisory about consuming fish because of the mercury. Almost every water body in the state of Missouri is impaired by mercury.

“There are no state or federal rules in effect now for mercury,’’ he added.

Dan Riedinger, a spokesman for Edison Electric Institute, which represents investor-owned utilities, said the EPA is moving forward with plans to regulate mercury, and is working with utilities to gather emissions data, but consumers need to expect higher costs and any EPA steps may not necessarily alleviate the problem.

Pollution control technologies can cost utilities millions of dollars, he said, and it’s difficult to know what the impact will be on consumers because mercury is only part of a larger effort to control other emissions, such as greenhouse gases. But there will be costs, he said.

Additionally, he said, some industry and EPA studies indicate 50 percent or more of the mercury coming down in the country is from sources outside U.S. borders, and whether new EPA rules will result in cleaner American lakes and streams remains to be seen.

“We need to make reductions in mercury emissions,” Riedinger said. “The question becomes in part one of expectations.”

Amy Bass, director of corporation communications for The Empire District Electric Co., said the Joplin-based utility continues to follow mercury issues and “will comment on any proposed regulations to protect the best interests of our customers and shareholders.

“We will comply with any new regulations,” she added.

Close to home

“Atmospheric deposition of mercury, it is true, might come from the far West or even Southeast Asia, but the heaviest deposits of mercury fall nearest to the emitting coal-fired power plant,’’ Midkiff said. “The states should be regulating that, but they are not.’’

Said Hatley: “Grand Lake is surrounded by power plants. A 1998 study by the EPA found that 14 percent of the mercury from a power plant falls out within a 13-mile radius and that 48 percent of the mercury falls out within a 60-mile radius.

“Sixty to 80 percent of the mercury in any given region is from local sources,’’ he said. “We have six plants within a 60-mile radius of the lake.’’

Hatley said it is a rite of passage in Oklahoma for a grandson or granddaughter to be taken to the farm pond to catch their first fish.

“My first fish was a perch,’’ he said. “I think farmers would be shocked to know that every water body in the state, including their farm pond, has been impacted by mercury.’’



Mad hatter

Mercury affects the central nervous system. The phrase “mad as a hatter’’ reflects a period in hatmaking when hatmaters used mercury to cure hats.



Mercury discharges

Total releases of mercury

United States-122,198

Kansas-682

Missouri-155

Oklahoma-254

Total releases of mercury compounds

United States-6,069,232

Kansas-2,353

Missouri-7,203

Oklahoma-20,103

Source: Environmental Protection Agency’s Toxic

Release Inventory for 2008, the last year the

information is available. The figures are for all

discharges of mercury into the air, water and land.





























Mercury discharges

United States Kansas Missouri Oklahoma

Total releases of mercury: 122,198 682 155 254

Total releases of mercury compounds: 6,069,232 2,353 7,203 20,103

Source: Environmental Protection Agency’s Toxic Release Inventory for 2008, the last year the information is available. The figures are for all discharges of mercury into the air, water and land.

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