Scientists are sweeping the sea floor from Chesapeake Bay to Cape Hatteras to find out whether millions of pounds of potentially harmful metal particles from coastal power plants are getting into the food we eat.

"The question is, where do they go?" says Leonard Pietrafesa, a North Carolina State University oceanographer. "Are they lying dormant somewhere, or are they being eaten by critters higher and higher up in the food chain?"In a four-year, $4 million federal study begun in February, Pietrafesa and scientists at Yale, Columbia, the University of South Florida, Old Dominion and Brookhaven National Laboratory are collecting sediment, plants, fish and other samples.

They hope to learn if heavy metals from 20 nuclear and 40 fossil-fuel plants in New York, New Jersey and Delaware cling to microscopic sea life on the shelf extending 60 miles from shore, where most East Coast seafood is caught, says Pierre Biscaye, a Columbia University marine geochemist.

The plants annually release 20 million pounds of metals such as mercury, lead, copper and cadmium that can harm humans in large doses, says Pietrafesa. If the study proves that power-plant byproducts remain on the shelf floor, the government may propose stiffer regulations says Helen McCammon, director of the DOE's Ecological Research Division. "If the nation is dumping in the ocean, we want to know what's happening to them . . .

"Are energy problems going to come back to haunt us?"