USA Today – October 29, 2007
Power plants are focus of drive to cut mercury
By Larry Wheeler, Gannett News Service
Despite decades of government attempts to regulate it, ban it and erase it from household use, the poisonous metal mercury remains a threat to the environment and public health, especially to children and to women of childbearing age.
As many as 600,000 babies may be born in the USA each year with irreversible brain damage because pregnant mothers ate mercury-contaminated fish, the Environmental Protection Agency says. Medical researchers are just beginning to explore such mercury exposure in adults, which can leave some people struggling through life in a disorienting “fish fog.” Nationwide, more than 8,000 lakes, rivers and bays are compromised by mercury’s toxic effects.
Mercury Emitter Map:
Where mercury falls in the USA:
Where our electricity comes from:
Where is all the mercury coming from and can something be done to stop it? A partial answer can be found in the nearly 500 coal-burning power plants that supply half the nation’s electricity. The $298-billion-a-year electric utility industry is the nation’s largest source of mercury air emissions and the latest target of federal and state clean-air regulations.
Mercury emissions in the USA have been cut nearly in half since 1990 as municipal, medical and hazardous-waste incinerators closed or installed modern pollution controls. But mercury from coal-burning power plants has risen, largely because there have been no federal limits on such emissions.
In 2005, about 500 electricity-generating power plants emitted 48.3 tons of mercury, an increase of 1% since 2000, according to a USA TODAY analysis of the EPA’s Toxics Release Inventory. Mercury emissions from all other industrial sources were collectively down 33% in the same period.
The electric power industry, which has plans to build an additional 153 coal-fired plants by 2030, says it is behaving responsibly. It is retrofitting old plants and building new ones with pollution-control equipment that will remove much of the mercury, with other pollutants, from flue gas.
“The industry recognizes that by combusting coal, there are things that get into the atmosphere,” says Michael Rossler of the Edison Electric Institute, an industry trade association. “Our industry has always been very good about wanting to comply with federal and state regulations.”
Two years ago, the EPA issued its first mercury regulation aimed at coal-fired plants. The EPA’s new Clean Air Mercury Rule, effective in 2010, gives energy companies until 2018 to cut mercury emissions to an industrywide 15 tons.
That cleanup timetable is not good enough for environmental advocacy groups. A coalition of more than a dozen states, Native American tribes and environmental groups has filed suit in the U.S. Court of Appeals in Washington, D.C., seeking to overturn the EPA rule and force the agency to get more mercury out of the air sooner.
James Pew, an attorney for Earthjustice, one of the environmental groups, calls the EPA rule a “free pass for the polluters.” It “means more mercury pollution, more waters made unsafe for fishing and more young children made susceptible to mercury contamination,” he says.
The most common route of human exposure to mercury is through eating fish contaminated with methyl mercury. Microorganisms in lakes and streams convert mercury emissions into methyl mercury, which accumulates at unhealthful levels in large fish.
Pew argues that in the waning days of the Clinton administration, the EPA legally committed the government to a more thorough cleanup as required by the Clean Air Act. Now, under pressure from industry, he says, Bush administration EPA officials have crafted their own interpretation of the law, giving power plants more time to meet less stringent emission goals.
EPA officials say that deep, rapid cuts in mercury emissions are unwarranted and too costly to the power industry and would produce nominal health benefits, because, in their view, most of the mercury deposited in U.S. lakes and streams comes from abroad.
“At the end of the day, we didn’t think it was appropriate and necessary” to adopt more stringent regulations, says Bob Meyers, the EPA’s acting chief of air programs.
The EPA mercury program also allows power plant operators to purchase mercury pollution credits from cleaner plants. Critics warn that the trading system could let the worst polluters off the hook and foster “hot spots” with dangerously high levels of mercury.
Effects of a daily diet of tuna
When Luke Lindley arrived at Stanford University in the fall of 2002, he made a decision that threw his health into a tailspin. Allergic to dairy products and nuts, the pre-med student skipped the campus dining hall and began eating canned tuna as an inexpensive, convenient and, he thought, healthful source of daily protein.
“It was just easier to pack a can of tuna and some bread and make a sandwich on campus,” says Lindley, who grew up in Twin Falls, Idaho. For months, Lindley’s daily diet included three to four 6-ounce cans of albacore (white) tuna.
Then the symptoms began. “I couldn’t sleep,” Lindley says. “And when I did manage to get two or three hours of sleep, I would wake up exhausted to the bone.”
Hitting the books, which had always come easily to Lindley, became a chore. “I would study four times as long to retain the same information that should have taken me a very short amount of time,” he says. “Each day was an ordeal.”
Campus doctors were unable to cure Lindley’s insomnia or relieve his agonizing gastrointestinal distress. Despite his growing health problems, Lindley maintained an accelerated class schedule and completed his undergraduate degree early, never suspecting the ever-present cans of tuna in his backpack may have poisoned him.
Once enrolled in medical school at the University of Minnesota in August 2005, Lindley again made his way to the campus clinic. A lab test found that Lindley’s hair had mercury concentrations 44 times the government’s safety threshold. He immediately eliminated tuna from his diet, took a year off from school and waited to get better.
“It took a good eight to nine months before things started to improve,” says Lindley, 23. “Gradually, I was able to sit and read a book without losing focus. My memory improved. I began feeling better about myself. My motor coordination improved, (and) the cramps and diarrhea slowly improved.”
A problem for ‘fishetarians’
Lindley’s troubling story is typical of a largely unrecognized health threat that appears to be linked to mercury in seafood, says Jane Hightower, a San Francisco doctor. Hightower’s 2003 research exposed elevated mercury levels in her own patients and touched off new concern over the issue.
Hightower identified dozens of patients whose blood mercury levels exceeded the EPA’s “safety” threshold of 5.8 micrograms of mercury per liter of blood. Study participants with the highest levels of mercury in their blood reported diets rich in large predator species fish, such as swordfish and ahi tuna. Many of them were affluent and well-educated, yet had no idea their favorite food was contributing to their illness, Hightower says.
“I call them ‘fishetarians,’ ” says Hightower, who also coined the term “fish fog” to describe their foggy mental state. “They are vegetarians, but they eat a lot of fish.”
Hightower’s research, first published in the medical journal Environmental Health Perspectives, brought an avalanche of responses from physicians and individuals, she says. Among them: Lindley and his Minnesota physician.
Hightower’s patients who eliminated or greatly curtailed consumption of fish species with elevated mercury saw their own blood mercury levels drop rapidly. For many, the exhaustion, the sleeping difficulties and other symptoms cleared up. But others said they weren’t the same, mentally, even after other symptoms disappeared, Hightower says.
Hightower and other consumer advocates say the government should do more to warn people about the risks posed by mercury in seafood. “For my patients, especially the fishetarians, I tell them they need to choose the lowest mercury-content fish,” she says.
Low-mercury seafood includes salmon, shrimp, flounder, scallops, anchovies and sardines.
No routine screening
Fish and shellfish are not routinely screened for mercury.
The Food and Drug Administration has a mercury “action level” that, if exceeded, could be used to remove contaminated seafood from the market. Yet the agency rarely exercises that authority.
“I call it the inaction level,” says Caryn Mandelbaum, environmental health analyst for GotMercury.org, a California-based environmental organization that endorses point-of-sale warnings about mercury in seafood.
California’s state attorney general and environmental groups used the state’s “right-to-know” law to pressure restaurants and a few grocery stores to post advisories warning customers of mercury hazards in certain fish.
But outside of California, fish-consumption advisories are rarely displayed on restaurant menus or at supermarkets.
Officials with the $55-billion-a-year U.S. seafood industry say their products are safe. “There are no documented cases of mercury poisoning in the U.S. as a result of eating seafood of any kind,” says Mary Anne Hansan, vice president of the U.S. Tuna Foundation.
Physicians and public health officials acknowledge it is extremely difficult to “prove” a direct link between eating a tuna steak and high blood mercury levels.
Anecdotal evidence isn’t hard to find. In Wisconsin, a report by the state’s Department of Health and Family Services found a strong correlation between fish consumption and high blood mercury levels. Among the subjects: a body builder whose diet included regular meals of tuna, and an attorney and his family who ate fish, often Chilean sea bass, four days a week.
Pregnant mothers who eat high-mercury fish can pass the toxin to a developing child. Exposure to methyl mercury in the womb, even at low concentrations, can alter brain and central nervous system development, resulting in reduced performance on vocabulary, learning and memory tests, according to a National Academy of Sciences assessment published in 2000.
The developing fetus is particularly vulnerable because organic methyl mercury can traverse the placental barrier and collect in the central nervous system and brain.
Deficits linked to mercury have been tracked in some patients into their teen years, suggesting that the damage mercury does in the womb is irreversible. Extremely high exposures can cause severe disabilities in newborns, including mental impairment, cerebral palsy, blindness and deafness.
The U.S. Centers for Disease Control and Prevention’s National Health and Nutrition Examination Survey of 1999-2002 measured mercury blood concentrations in a representative sample of 3,600 women and 1,500 children.
The study found that 94% of U.S. women of childbearing age had blood mercury levels at or below the threshold the EPA considers safe. But it is the 6% of U.S. women with blood mercury levels above the EPA threshold who have driven the public health debate.
Because newborns are not routinely screened for mercury, there are only government estimates of how many actually have unhealthy blood mercury levels.
Fishing on Lake Superior
Native Americans, especially those in the Northeast and upper Midwest, where fishing is a way of life, are among the U.S. residents who may be overexposed to the dangers of mercury in seafood.
Many have been forced to take into account the dangers of mercury as they pursue centuries-old fishing traditions. “Tribal members are very aware of the contaminants in fish,” says Matt Hudson, an environmental biologist with the Great Lakes Indian Fish and Wildlife Commission. “They have to be aware both from a commercial and personal health standpoint.”
Marvin Defoe Jr. is a Native American who fishes for walleye and other species in Lake Superior because that’s what he learned from his father. Now he’s teaching his son the practices of the Red Cliff Band of Lake Superior Chippewa Indians. “That lake is our garden,” says Defoe, 49, whose nets are now set in the water where Wisconsin’s Bayfield Peninsula juts into Lake Superior.
When Defoe harvests fish from smaller inland lakes each spring, as the walleye are spawning, he bags the catch and attaches a warning that the fish could contain dangerous amounts of mercury.
He follows a detailed set of color-coded mercury maps that reflect the latest scientific data about mercury concentrations. The maps spell out exactly how often it is safe to eat walleye from each lake.
In the cleanest lakes, the maps indicate, it’s OK for even pregnant women, women of childbearing age and children younger than 15 to eat up to eight meals a month. Walleye from other lakes is OK if only one meal a month is eaten. At some lakes, red on the map, locals of all ages are told: “Do not eat ogaa (walleye) from these lakes.”
Piggyback pollution controls
The EPA’s new regulation allows many coal-burning plants to achieve mercury emissions reductions by installing pollution-control devices whose primary function is to remove other pollutants — sulfur dioxide, nitrogen oxides and particulate matter — that are linked to global warming, asthma and lung and heart diseases.
The regulation was indeed crafted to piggyback on other pollution controls, says Jeff Holmstead, a former EPA executive who oversaw creation of the Clean Air Mercury Rule. “As a matter of good environmental analysis, (mercury) is not that big of an issue,” says Holmstead, now an attorney with Bracewell & Giuliani, a law firm whose clients include power companies.
Environmentalists and some state officials argue the EPA is circumventing the Clean Air Act by making mercury removal incidental to other pollution priorities.
Twenty-two states disagree with the EPA’s approach and are pursuing tougher standards on their own. New Jersey, for example, has mandated a 90% cut in mercury emissions from 10 coal-burning power plants by 2012, six years ahead of the EPA deadline.
The other states with tougher mercury air regulations are Arizona, California, Connecticut, Colorado, Delaware, Idaho, Illinois, Maryland, Maine, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, New Mexico, New York, Oregon, Pennsylvania, Utah, Washington and Wisconsin.
Local or global problem?
Even if mercury emissions from power plants and other U.S. industrial sources were eliminated, U.S. rivers, lakes and bays would receive significant amounts of the metal from a global cloud of mercury.
Natural sources, such as volcanoes and forest fires, along with industrial facilities in Asia, South Africa and Europe, are responsible for most of the global airborne mercury pool, according to a United Nations report.
The hottest debate is whether the mercury deposited in the USA comes from abroad or from domestic industries.
The EPA estimates that less than half of all mercury that falls onto U.S. soil and water comes from domestic industrial sources. It says less than 8% of that is from domestic coal-burning power plants.
Maps compiled by the EPA, based on computer simulations, indicate that mercury is not evenly deposited across the continental U.S., suggesting local emissions may play a role, as well.
The country’s largest area of highest mercury deposition looks like a plume stretching from the Mississippi River through Kentucky, across West Virginia and Pennsylvania, all the way to Massachusetts. There also are pockets in the South, on the West Coast and in Nevada and Arizona.
Energy industry executives argue that the small amount of mercury their coal-burning plants deposit make stiffer abatement unwarranted. “Everything that goes up does not come down, or it certainly doesn’t come down in the same place,” says the Edison Electric Institute’s Rossler.
Environmentalists counter that power plant emissions, particularly oxidized mercury, are indeed to blame. “Studies show that it actually falls fairly close to the stack,” says Eric Schaeffer, director of the Environmental Integrity Project.
There is evidence that mercury emissions from power plants and other polluters can contribute to “biological” hot spots where fish and wildlife have unsafe concentrations of methyl mercury, says David Evers, a researcher with the Biodiversity Research Institute of Gorham, Maine. As much as 65% of mercury deposited in a portion of the northeast USA could be attributed to regional power plants and other industries, Evers says.
Earlier research in Florida found mercury levels in Everglades wildlife quickly fell after federal regulations brought about a steep decline in mercury emissions from South Florida municipal, medical and hazardous-waste incinerators.
Although mercury can’t be eliminated, it can be reduced, scientists say. Says Evers: “We can act globally by cleaning up our backyards and making a difference.”