Florida a focus of debate over mercury

By Elizabeth Shogren
Los Angeles Times

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EVERGLADES NATIONAL PARK, Fla. — Two decades ago, residents of two Florida Panhandle towns were so concerned about a hazardous-waste site near the Chipola River that state officials agreed to monitor the fish there for five years.

They did not detect any hazardous-waste contamination in the fish, but they did find mysteriously high levels of mercury.

Intrigued, they kept digging.

Even higher levels of mercury turned up farther south, in the pristine reaches of the Everglades, the subtropical wilderness that sprawls across more than 2 million acres of central and southern Florida.

Eventually, scientists traced the source of the mercury not to toxic discharges into the groundwater, but to emissions into the air — a problem since documented in all but six states.

The cleanup of mercury emissions is an issue the Bush administration is required to address no later than today, which makes the success that Florida officials believe they have had in reversing the trend all the more significant.

Thanks to tough state regulations controlling air pollution from waste incinerators, the main source of mercury emissions in Florida, levels of the substance in largemouth bass and wading birds in the Everglades have dropped 60 percent to 70 percent since their peak in the mid-1990s.

That improvement has come far faster than anyone had predicted, said Tom Atkeson of the state's Department of Environmental Protection.

Deadline for regulations today

Forty-four states have detected levels of mercury in fish high enough that health officials warn against eating certain species from specific bodies of water and advise limiting consumption of others.

Under the terms of a 1998 lawsuit settlement between environmentalists and the Environmental Protection Agency (EPA), the federal government must announce by today its proposals for regulating mercury emissions from the largest remaining source of such pollution: coal-fired power plants.

State regulators, public-health professionals and environmental activists say that Florida's positive experience cleaning up mercury in the Everglades makes a strong case for forceful federal action.

But the Bush administration favors a more gradual approach that would not require deep cuts in mercury emissions until 2018, said EPA administrator Michael Leavitt. The administration's preferred option would use a market-based trading system to allow companies that reduced emissions below their cap to trade pollution credits with companies that clean up more slowly.

And the electricity-generating industry warns that requiring rapid reductions in mercury emissions could cause some utilities to switch from coal to natural gas and to increase electricity prices, without significant gains for public health.

Mercury in air pollution

Mercury is a naturally occurring substance that can be released into the atmosphere from a variety of sources, including volcanoes, forest fires, incinerators and coal combustion.

A small percentage of the mercury particles and gas emitted as air pollution are transformed into methylmercury, a particularly toxic form, after they fall into waterways. Methylmercury "bioaccumulates" in fish and its concentration increases as it passes up the food chain.

Developing fetuses and young children are highly sensitive to methylmercury exposure, which can cause significant neurological and developmental damage, such as cerebral palsy, mental retardation and delays in walking and talking.

The Centers for Disease Control and Prevention earlier this year reported that 8 percent of women of childbearing age had levels of mercury in their blood exceeding the precautionary standard set by the EPA. As a result, the CDC said, more than 300,000 newborns might have been exposed before birth to mercury concentrations high enough to increase the risk of neurological problems.

"Even small increases in mercury exposure are causing deficits in brain function," said Philippe Grandjean, a professor at Harvard University's school of public health. "The brain is a unique resource. We don't want to lose any brain capacity on behalf of some pollution that can be prevented."

Officials in Florida were inspired to take action after high levels of mercury showed up in largemouth bass, one of the Everglades' signature fish and a lure for anglers. They were also concerned that mercury posed risks for wildlife that feed on the fish, among them the Florida panther, which is on the federal endangered-species list, and many varieties of wading birds.

In 1989, Atkeson — who at the time worked for the state Health Department — and colleagues from other agencies received funding to test fish in the Everglades. They found mercury levels higher than 2 parts per million, several times higher than the 0.3 parts per million the EPA considers safe for eating.

"That's when we felt something was real," Atkeson said.

The director of the department then ordered that multiple fish be taken from 10 sites, including three popular fishing locations.

A state regulation adopted in 1990 to control other types of pollution from incinerators caused some decline in mercury emissions. In 1993, Florida was the first state to adopt a rule directly addressing mercury emissions from municipal-waste incinerators, and the federal government followed with a nationwide rule.

Atkeson says the state is convinced that despite the distinct ecology of the Everglades, its success in decreasing contamination applies broadly. "The science is universal," he said.

But Leonard Levin, who heads the mercury work at the utility-industry-funded Electric Power Research Institute, said it would be wrong to assume that Florida's experience means that slashing mercury pollution from power plants elsewhere would quickly reduce mercury in fish.

"I don't feel that case has been made," Levin said. "I'm skeptical that you'll see the same impact on a national scale that you saw in Florida."

One reason, he said, is that power plants emit a smaller portion of the kind of mercury that tends to drop relatively close to the source. On average, about 60 percent of the mercury emissions from power plants is elemental mercury, which tends to stay in the atmosphere longer and could fall to Earth anywhere, he said.

"Our modeling has shown that for most of the country, more than 90 percent of the land area, there is a very small change in deposition for a big change in emissions," Levin said.

Atkeson says 20 years of data collection has given Florida something better than just modeling: scientific evidence. Officials regularly sampled largemouth bass from several spots around the state. They also analyzed the sediment that makes up the floor of the vast marsh.

These data, they say, provide ample evidence that air pollution is the prime cause of mercury contamination in fish and that stringent emission regulations are tackling the problem.

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