Superior Tube Co., a Collegeville manufacturer that has released some of the nation's highest airborne amounts of trichloroethylene, a suspected carcinogen, announced today that it is phasing out use of the chemical.

Company president Tony Jost said the TCE would be replaced with a less hazardous chemical.

The company has asked the Pennsylvania Department of Environmental Protection for permission to modify its procedures. If approved, Jost said, the work could be completed by the end of April.

Charles McPhedran of Citizens for Pennsylvania's Future, a key critic of the company's practices, said Superior was making "a big step forward."

Company officials said the new process would be state of the art and would meet or exceed all the changes that have been vigorously sought by area residents, legislators and the environmental community.

"Our project is unique," Jost said. "No one has ever done what we're doing to this kind of equipment at this scale."

The company manufactures extremely thin tubing for the medical, aerospace and defense industries. TCE is used as a degreaser during the process, and the company had been emitting 70 tons a year of TCE into the air.

Air monitors had detected the state's highest levels of TCE in the Collegeville area near Superior and another tubing manufacturer, Accellent Inc., which is also working to reduce emissions.

The amount being emitted was within the level permitted by the DEP, but after air samples at nearby locations showed high levels of TCE, the agency asked for a voluntary reduction from both companies.

Jost said the substitute degreaser would be n-propyl bromide, which is not a hazardous air pollutant.

Superior also has requested that the DEP lower the amount of emissions mentioned in the permit to reflect the 52 percent reduction it has achieved voluntarily. The company said that modifying the permit would make the voluntary reductions "permanent and legally enforceable."

That change had also been sought by critics who worried that the company would not be held to tighter emission standards if its reductions were made voluntarily.

Jost would not disclose how much the changes are costing the privately owned company. The expense would be "substantial," he said, "a significant investment."

McPhedran, senior attorney for Citizens for Pennsylvania's Future, which recently released a report outlining ways the company could reduce emissions, praised the move.

"This is a very important step by a company that seems to be recognizing its obligations to its neighbors. This is very good," McPhedran said.

U.S. Rep. Joe Sestak (D. Pa.) said in a statement that he was "pleased" with Superior's efforts.

Sestak met with company officials two weeks ago. He said he was "impressed by the professional approach and attitude of their management to ensure that the issue of TCE emissions is fully and rapidly addressed, as well as their commitment to being good neighbors to Collegeville-area residents."