Usually when talk turns to mercury contamination it's all about the fish.

But the price of a chicken dinner is what it would cost utility customers in Pennsylvania to have the state's coal-burning power plants reduce emissions of the neurotoxin mercury by 90 percent in eight years, according to the Rev. William Thwing.

Mr. Thwing, representing the Pennsylvania Council of Churches and his 400-member Ebensburg, Cambria County, congregation, was one of 28 people who spoke at a public hearing in Pittsburgh yesterday in support of a proposed state rule on power plants' mercury emissions that is tougher than the federal regulation. The state Environmental Quality Board hearing lasted three hours.

It would cost the state's 36 coal-fired power plants an estimated $223 million to install the mercury controls needed, Mr. Thwing said, and if the entire cost was passed on to customers, each residential electric bill would go up about $1.08 a month, or $13 a year.

"Mercury poses an extreme and unnecessary risk and the solution is simple, quick and relatively inexpensive," he said. "For $13 a year, the price of one good chicken dinner, you can save all the children in Pennsylvania."

The hearing was the first of three on the Rendell administration's proposed mercury rule that would cut emissions 80 percent by 2010 and 90 percent by 2015.

The Bush administration adopted weaker mercury controls last July that require a 70 percent reduction by 2018 but allow smaller and older plants to avoid installing controls if they purchase "credits" from other power plants that have reduced emissions by more than required -- a so-called cap-and-trade program.

Kenneth Bowman, regional director of the state Department of Environmental Protection, said the major problem with the federal regulation is the cap-and-trade provision.

"The power companies could over-control power plants in Western states," he said, "and we won't get the controls we need."

Pennsylvania and 15 other states have sued the U.S. Environmental Protection Agency in federal court, claiming the cap-and-trade provision would hurt efforts to reduce mercury emissions.

Pennsylvania utility companies and industries emit more than 5 tons of mercury into the air a year, second only to Texas. And the commonwealth is downwind from Ohio, the third largest emitter of mercury, a neurotoxin that moves from the air to waterways and accumulates in fish flesh.

When ingested, methyl mercury is especially harmful to pregnant women, babies and children. High-level exposure can cause attention and language deficits, memory loss, autism, mental retardation, and impaired vision and motor functions.

"We are gravely concerned about the increasing number of children with autism and attention deficit disorders," said Kathy Lawson, director of the Healthy Children Project for the Learning Disability Association of Pennsylvania. "We know there is a connection between mercury and the rising incidence of cognitive disabilities."

Frank Burke, representing Consol Energy and the Pennsylvania Coal Association, spoke in opposition to the proposed state rule, saying it would hurt the market for Pennsylvania coal, which has a higher mercury content than any other coal mined in the United States.

"If Pennsylvania air quality standards are more onerous, they can make Pennsylvania coal more expensive to use and create potential loss of market share," Mr. Burke said. "The state should be required to do a quantitative cost-benefit analysis to determine the benefits of going beyond the federal rule."

Two speakers from unions representing power plant workers said the proposed state rule could force some smaller, older power plants to close and cost utility workers jobs.

The next hearing will be today in Harrisburg. The last is scheduled for tomorrow in Norristown, Montgomery County.

The proposed rule could get final Environmental Quality Board approval before the end of November.

Legislation to block the board from acting on the rule was passed by the Republican-controlled state Senate last month after intense lobbying by utility companies and the coal industry. The state House has not yet scheduled a vote.