WASHINGTON — Concentrations of mercury in the rainwater of several southeastern and Gulf Coast states exceed the safe level established by the Environmental Protection Agency for lake water by as much as 96 times, an environmental group reported Thursday.
The National Wildlife Federation said EPA mercury sampling stations in Georgia, Texas, Florida and five other Southern states showed mercury levels that would make fish toxic to humans who consumed them.
The form of mercury found in contaminated fish destroys nerve cells and easily crosses the placenta into unborn babies, researchers say. The National Academy of Sciences has warned that consumption of contaminated fish by pregnant women can lead to children with learning disabilities.
The federation, largest environmental organization in the country, called on the EPA to crack down on the sources of mercury in the atmosphere, especially coal-burning electric power plants.
Rain samples collected in the Okefenokee National Wildlife Refuge in southern Georgia's Charlton County had concentrations of mercury as high as 275 parts per trillion, which is 78 times higher than the EPA-defined safe level for lake water, the report stated. One sampling site in Louisiana showed levels 96 times the safe level.
More than 93 percent of the Okefenokee samples collected between 1998 and 1992 exceeded the safe lake level, the federation reported.
The Georgia Department of Environmental Protection has identified 2,247 miles of river and 26,051 acres of lakes as contaminated with mercury to a degree that should cause people to restrict the quantity of fish they consume from those waters.
Because it tends to concentrate in the flesh of fish, especially those at the top of aquatic "food chains," fish often will have levels of mercury thousands of times higher than the surrounding water, biologists say.
An author of the report, "Cycle of Harm: Mercury's Pathway from Rain to Fish in the Environment," acknowledged in an interview that not all of the mercury that contaminates rainwater finds its way into rivers or lakes.
Much is left behind in soil as rainwater runoff makes its way into the nearest stream, said Felice Stadler, a mercury specialist with the organization.
Even so, state environmental agencies in Florida, Georgia and many other states have found mercury levels high enough to prompt them to recommend that people limit the amount of fish they eat from thousands of miles of rivers and hundreds of lakes.
"Sixty percent of all the mercury that deposits into lakes and streams comes from domestic sources, and coal-fired power plants are the largest source," Stadler added.
A spokesman for a group of power companies that have lobbied in favor of President Bush's Clear Skies Initiative for regulating air pollution from power plants said the federation's recommendations would be "counterproductive."
Scott Segal, director of the Electric Reliability Coordinating Council, said the report calls for "old-fashioned litigious regulatory approaches."
He said that by allowing power companies more flexibility, the Clear Skies Initiative would result in greater efficiency and therefore less pollution.
The initiative sets national caps on airborne pollutants and allows polluters to swap credits. It calls for a 70 percent reduction in mercury pollution, less than currently required by the Clean Air Act.
Dan Reidinger, a spokesman for the Edison Electric Institute, trade association of the nation's electric industry, said power companies "have committed to reducing mercury pollution substantially."
However, he said computer model studies suggest 40 to 70 percent of the mercury floating in America's atmosphere originates outside the country, from volcanoes and industries in other countries.
"Some of the calls for more extreme reductions in emissions, such as 90 percent that some environmental groups are calling for, would raise electricity costs without providing any measurable health benefit," he said.
Jeff Nesmith's e-mail address is jeffn@coxnews.com