WASHINGTON – The export of highly toxic mercury would be banned and federal agencies prohibited from selling or distributing mercury under legislation the House passed Tuesday.

The United States currently exports mercury for use in thousands of small-scale gold mines, often in developing countries. Environmental and health groups warn that mercury toxins from those sites can return to this country, either through the atmosphere or contaminated fish, posing particular danger to young children and the fetuses of pregnant women.

Rep. Tom Allen, D-Maine, a sponsor of the bill, cited estimates that up to one-third of U.S. mercury air pollution travels into the country from Asia, where mercury pollution is extensive. He said that much of the fish Americans eat, including tuna, is imported from off the coasts of Asia and South America where the use of mercury in small-scale gold mining is widespread.