Days after a scientific panel urged the government to send a strong warning to pregnant women and children about mercury levels in certain fish, the Bush administration is proposing to give power plants up to 15 years to install technology to reduce mercury pollution (search).

The proposal, released by the Environmental Protection Agency (search) on Monday, would require immediate action in some cases once the new regulations took effect a year from now.

The move comes a week after scientists told the Food and Drug Administration (search) that it should issue stronger warnings to pregnant women and young children about mercury levels in fish, particularly tuna. White, or albacore, tuna has nearly three times as much mercury as cheaper "light" tuna.

Mercury pollution can taint fish once it enters water and turns into a more dangerous form, methyl mercury (search). In high levels, it can damage the growing brains of fetuses and young children.

EPA's first-ever proposed controls on mercury pollution from power plants would ease limits envisioned by the Clinton administration, letting owners in some cases delay meeting requirements until 2018. They would let industry meet the first six years' goals by using pollution controls already installed to stem smog and acid rain.

The controls were issued to meet a deadline under a settlement with the Natural Resources Defense Council (search). The group sued during the Clinton administration to force mercury limits on power plants. The rule must be made final within a year.

"These actions represent the largest air reductions of any kind not specifically mandated by Congress," Mike Leavitt, the new EPA administrator, said Monday. "We are calling for the largest single industry investment in any clean air program in U.S. history."

In a related measure, EPA proposed that power plants in 30 states cut smog- and soot-forming chemicals from their smokestacks.

EPA estimates the industry will pay at least $5 billion to comply with both programs.

The Bush administration mercury plan is a departure from the Clinton administration approach. In 2001, EPA estimated that mercury could be cut by as much as 90 percent, to 5.5 tons, by 2008 if the best available technology were used as the Clinton EPA had hoped, according to EPA documents obtained by advocacy group National Environmental Trust (search).

But the White House and Leavitt want to let utilities meet mercury pollution limits the first six years using the benefits of controls installed for other pollutants that cause smog and acid rain.

That approach, EPA says, would eliminate about 14 tons a year of mercury emissions from the currently unregulated 48 tons a year generated by coal-fired power plants. Such plants account for about 40 percent of the nation's mercury pollution.

After that, the proposal would cut an additional 19 tons a year of mercury emissions, EPA says. The result would be a 70 percent reduction - from 48 tons to 15 tons - by 2018, the agency says.

The Clinton administration listed mercury as a "hazardous air pollutant." The Bush administration would undo that by placing mercury into a less strict category of the Clean Air Act, which will allow companies to buy and sell pollution rights with other plants.

"What we're trying to do is to maximize the total reduction of pollution from power plants," said Jeffrey Holmstead, head of EPA's air office. He said an interim cap on tons of mercury pollution would be set between "the high 20s to low 30s" by 2010.

Proponents frequently point to the acid rain trading program begun in 1990 as the model for using market forces to reward companies that surpass their pollution reduction targets. But it would mean the toughest mercury requirements would not take force until 2018.

EPA's regulation for cutting smog and soot would require power plants in 30 states to cut sulfur dioxide emissions, which contain soot and lead to acid rain, to 3.2 million tons by 2015 from current levels of about 10 million tons a year. It also would require cutting smog-forming nitrogen oxides to 1.7 million tons from current levels of 4 million tons.