The Sierra Club is reporting that the country's largest hair-sampling project to check for mercury has found that nationally, 20 percent of women of child-bearing age have more of the toxic substance than recommended by the Environmental Protection Agency.

In Utah, about 10 percent of such women showed what the environmental group termed dangerous amounts, "less than the national average, but still a major concern for expectant or soon-to-be expectant mothers," said Tim Wagner, Sierra Club spokesman in Utah.

The group's press release added that when Utah men and women are counted, 15 percent have that level of the contaminant.

"The study comes at a time of growing concern over mercury in Utah," Wagner added in a press release, "whether it comes from existing coal-fired power plants or gold mines in Nevada."

He added that the study was carried out by the Environmental Quality Institute at the University of North Carolina-Asheville. It shows what the group has believed all along about toxic mercury in Utah, according to Wagner.

"We have a problem with this stuff getting into our bodies and we need to address it by, among other things, getting the state to move towards cleaner sources of energy in order to keep women and children mercury-free," Wagner said.

He said coal-burning power plants are the biggest mercury polluter in America. The material falls into lakes, streams and oceans, concentrating in fish and shellfish, which are then consumed by people, he said.