A coalition of environmentalists has filed a suit demanding that state officials take steps to protect the public from fine particulate pollution.

The groups - Preservation Counsel, Utah Environment Center and Utah Valley Citizens for Clean Air - filed suit in U.S. District Court Friday. They claim the state has failed to submit a plan to control particulates of 10 microns or smaller in size.These particles are so tiny that they can lodge in the lungs and cause health problems. The suit claims the state has not filed an implementation plan, designed to control dust, with the Environmental Protection Agency.

Unless the court orders the state to file a plan to control the PM10 pollution, the suit claims, "defendants will continue to violate the (Clean Air) Act."

The suit says that in Utah, particulates of this size have reached concentrations much higher than permitted by federal standards.