The Environmental Protection Agency estimates medical mercury thermometers contribute about 17 tons of mercury to solid waste per year, said Sen. Susan Collins, a Maine Republican and chief sponsor of the measure.

The bill calls for a nationwide ban on the sale of such thermometers as well as a grant program to help consumers exchange them for digital ones or other alternatives.

"Mercury fever thermometers are very easily broken. When this happens, the improper disposal of the mercury can have severe environmental and physical consequences," Collins said.

"One mercury thermometer contains about one gram of mercury," said Collins, "enough mercury to contaminate all the fish in a 20-acre (8 hectare) lake."

Her bill would also create an interagency task force, headed by the EPA, to address the problem of the global circulation of mercury and ways to reduce the mercury threat.