County officials in Davis and Salt Lake counties are asking their health departments to again review how much fluoride is added to area drinking water after a request Tuesday by Waterwatch of Layton.

Last week, the U.S. Department of Health and Human Services proposed changing the recommended fluoride level to 0.7 milligrams per liter of water. The standard since 1962 has been a range of 0.7 to 1.2 milligrams per liter, but officials are now seeing a rise in adolescents of fluorosis, or spotting on teeth caused by too much fluoride.

The two counties have already dropped levels to 0.7 milligrams in October. But Waterwatch Director Lorna Rosenstein appeared before the Salt Lake County Council and the Davis County Commission Tuesday to urge lowering the target.

She cited a 2006 National Research Council review that showed dental fluorosis can occur in youth when drinking water contains even less than the new standard.

Rosenstein also asked that both counties notify every household receiving fluoridated tap water — in English and Spanish — of potential risks of fluorosis to infants and young children. It should explain that boiling water does not change its fluoride level, she added.

In 2006, the Centers for Disease Control and the American Dental Association advised using non-fluoridated drinking water for infants, in particular, for mixing formula, Rosenstein said.

Fluorosis “is a permanent disfigurement,” Rosenstein said of teeth discolored by the condition, noting insurance companies view the fix as elective and do not cover those costs.

Lewis Garrett, executive director of the Davis County Health Department, says it issued an advisory in 2006, and questioned the need for more.

Only a few populous areas in Utah fluoridate the water — Davis and Salt Lake counties, along with Brigham City and Helper.

State Sen. Allen Christensen, R-North Ogden, a pediatric dentist and fluoride fan from Weber County, said he sees about one case of fluorosis each week out of 300 to 400 patients.

“They come mostly from areas where natural overfluoridation exists,” Christensen said, adding that he supports the ongoing review and adjustment of fluoride levels.