Health Threat of Mercury Overblown, Scientists Say

Published May 1, 2004

Controversy over the health effects of mercury in fish and shellfish and the Bush administration’s plan to reduce mercury emissions by utilities dominated the debate over environmental policy in recent weeks. Now, scientists say the health threat of current levels of mercury exposure has been exaggerated.

Joint EPA/FDA Advisory

The Environmental Protection Agency and the Food and Drug Administration on March 19 announced a joint consumer advisory on methylmercury in fish and shellfish. The advisory, aimed at reducing mercury exposure in women who may become pregnant, women who are pregnant, nursing mothers, and young children, unifies advice from the two agencies and supersedes their 2001 advisories.

The joint advisory emphasized the small hypothetical risk from increased exposure to mercury is offset by the benefits of eating fish. “Consumers should know that fish and shellfish can be important parts of a healthy and balanced diet,” stated the advisory. “They are good sources of high-quality protein and other essential nutrients; however, as a matter of prudence, women might wish to modify the amount and type of fish they consume if they are planning to become pregnant, are pregnant, nursing, or feeding a young child.”

The advisory offered three recommendations for pregnant mothers and mothers of young children. According to EPA and FDA, women covered by the advisory should:

1. Avoid eating shark, swordfish, king mackerel, or tilefish because these species tend to contain high levels of mercury.

2. Eat up to 12 ounces (two average meals) a week of a variety of fish and shellfish–such as shrimp, canned light tuna, salmon, pollock, and catfish–that tend to be lower in mercury.

3. Check local advisories about the safety of fish caught by family and friends in local lakes, rivers, and coastal areas.

According to the EPA/FDA advisory, women following the advisory “will receive the benefits of eating fish and shellfish and be confident that they have reduced their exposure to the harmful effects of mercury.”

“Research shows that most people’s fish consumption does not cause a health problem,” noted the advisory. “Fish and shellfish are an important part of a healthy diet. Fish and shellfish contain high-quality protein and other essential nutrients, are low in saturated fat, and contain omega-3 fatty acids.

“A well-balanced diet that includes a variety of fish and shellfish can contribute to heart health and children’s proper growth and development,” continued the advisory. “So, women and young children in particular should include fish or shellfish in their diets due to the many nutritional benefits.”

Liberal Democrats Attack Bush

The EPA/FDA advisory was issued in the midst of a media blitz by liberal environmental groups opposed to the Bush administration’s proposal to regulate industrial mercury emissions.

In late 2003, the Bush EPA proposed a plan to cut mercury emissions from power plants by 40 percent by 2010, and 70 percent by 2018. The administration intends to announce a final regulation late in 2004. (See “EPA Proposes Mercury Limits,” Environment & Climate News, January 2004.)

Although the Bush proposal would mark the first time the federal government has regulated mercury emissions, activist groups nevertheless are criticizing the administration for not proposing even bigger cuts in emissions and for including cap-and-trade mechanisms in the regulations.

While the Clinton EPA chose not to regulate mercury emissions during its eight-year tenure, then-administrator Carol Browner is now a vocal proponent of mercury regulations. She opposes any program that would not require an across-the-board 90 percent reduction in mercury emissions.

“We had evidence that you could get there. … It is possible. It is doable,” Browner said at a recent news conference. She argued EPA should require mercury reductions to ” the lowest level achievable rather than asking industry, ‘What do you feel like doing?'”

Technology and Emissions Trading

“There currently is no commercially available mercury-specific control technology,” countered Dan Riedinger, a spokesman for the Edison Electric Institute. “Our hope is that toward the end of this decade, we will have at least identified new technologies for removing mercury from different coal types and using different boiler configurations.

“It is possible to get a 90 percent reduction in mercury emissions in certain coal types and certain boilers, but to then make the jump and assert a 90 percent reduction is possible across the entire industry is simply impossible,” added Riedinger. “The actual range of reductions varies, from between about 17 percent to 90 percent.”

Said EPA Administrator Mike Leavitt, “In the near future, will there be technology capable of getting a 90 percent reduction of mercury from coal-fired power plants? No. Technology is simply not there for now. Our proposed rule will achieve a 69 percent reduction in mercury emissions. Our preferred approach takes us away from ‘command and control’ and instead provides a proven, market-based emissions ‘cap-and-trade’ system. The EPA sets mandatory industry reduction targets emission caps and dates and gives utilities flexibility in finding the best way to meet them.”

“For some pollutants, setting a cap on total emissions, while letting polluters buy and sell emission rights, is a cost-efficient way to reduce pollution,” explained the New York Times‘s Paul Krugman in an April 6 editorial. “The cap-and-trade system for sulfur dioxide,” Krugman added, “has been a big success.”

Despite support for cap-and-trade by one of the Times‘ most liberal columnists, environmental activist groups have consistently opposed such mechanisms, and they remained true to form with respect to the proposed mercury regulations.

“The debate is what’s the best option, given the available technology. And we think that, given the state of technology, cap-and-trade is better and we’re leaning that way,” said EPA spokeswoman Cynthia Bergman.

Scientists Say Little Threat

While political debate rages about what regulatory method would most effectively and efficiently reduce mercury emissions, the scientific debate is largely settled: Mercury poses little or no threat to the health and well-being of U.S. citizens.

Steven Milloy, an adjunct scholar at the Cato Institute and author of Junk Science Judo: Self-Defense Against Health Scares and Scams, questioned the need for even the limited EPA/FDA advisory. Said Milloy, “There’s no evidence the rules will protect anyone, and they’re likely only to foster undue concern about an important part of our food supply.

“It’s certainly true such larger fish tend to have higher levels of mercury in their tissue, since mercury levels tend to accumulate up the food chain,” Milloy added. “But unless women are consuming fish that have been exposed to industrial-level concentrations of mercury for extended periods of time, as Japanese women in the vicinity of Minamata Bay did during the 1950s, it’s not at all clear that consuming large fish is any sort of health risk.”

More than half the mercury in the Earth and its environment comes from natural sources. Man-made sources, primarily power plants, produce the remainder of environmental mercury. U.S. power plants account for only 1 percent of global environmental mercury, according to the Center for Science and Public Policy, and those emissions are already in steep decline.

According to Harvard-Smithsonian physicist Dr. Willie Soon, “Recent findings by the Centers for Disease Control show that the level of mercury found in humans is far below the threshold of health risk, even for sensitive populations.”

Added Soon, “Placing heavier regulatory burdens on already-clean U.S. power plants that will drive up energy prices makes little economic sense.”

“It’s quite possible we could spend $4 billion per year reducing mercury and end up with nothing to show for it but higher electricity bills,” concurred Joel Schwartz, contributing author to Tech Central Station and a visiting fellow at the American Enterprise Institute.

Indeed, activist claims that women and children are being harmed by mercury are “a whole lotta baloney,” according to an April 8 editorial in the Wall Street Journal.

“About the only thing (such claims) prove is that trusting ‘environmentalists’ in a political debate is harmful to your health and the national well being,” stated the Journal. “There’s no evidence to suggest that cutting emissions will reduce mercury in fish. There’s also no credible science showing America faces any health threat at all from current fish consumption.”


James M. Taylor is managing editor of Environment & Climate News. His email address is [email protected].