CDC Director Julie Gerberding is coming under fire from business leaders, labor unions and lawmakers for allegedly playing politics by refusing to reappoint the widely-respected director of the agency's worker safety division.

Dr. John Howard's six-year term as director of CDC's National Institute for Occupational Safety and Health (NIOSH) will expire Monday. Gerberding met with Howard last week at the Centers for Disease Control and Prevention's headquarters in Atlanta to inform him she would not be reappointing him to the position.

"Frankly we would have thought this was a no-brainer," said Marc Freedman, director of labor law policy at the U.S. Chamber of Commerce. The world's largest business federation is among the many diverse groups that had urged federal officials to reappoint Howard.

"Here he comes in with the business community in various forms, the safety community in various forms, the Democrats and even labor — on a silver platter," Freedman said. "So I'm rather struck by their unwillingness. But it wasn't 'they' in general. It was Dr. Gerberding."

A spokesperson for Gerberding said she was traveling Wednesday and unavailable for comment. Howard is not giving interviews, his spokesman said.

Lacking any stated performance reason for Howard's ouster, lawmakers and others who work with NIOSH said they believe that politics or personal animosity are at the root of Gerberding's action.

"Dr. Howard was fired because he was a dedicated professional, rather than a political hack," U.S. Rep. Carolyn Maloney (D-NY) said Wednesday. "He believed, as most Americans do, that our country has a moral obligation to help those who are suffering as a result of the 9/11 attacks."

Maloney and other Congressional Democrats have been particularly vocal in their support for Howard, who as NIOSH director has been responsible for federal health programs for 9/11 responders who were exposed to toxins at Ground Zero.

NIOSH, headquartered in Washington, D.C., conducts research and makes recommendations on preventing work-related illnesses, injuries and deaths.

Others who have contacted Gerberding's boss, U.S. Secretary of Health and Human Services Michael Leavitt, and other federal officials seeking Howard's reappointment include numerous professional safety organizations, the AFL-CIO and other labor groups. Leavitt's office did not respond to a request for comment.

Some of the groups said they were aware of what they described as "personal differences" between Gerberding and Howard, but said they didn't know the specifics.

"We know there was some friction, but I don't know the source of it," said Freedman. "It's unfortunate that others in the administration were not willing to override her."

The American Society of Safety Engineers' spokeswoman Diane Hurns said her organization's members are very concerned about Howard's firing. "He knows his stuff, he's passionate and he's led NIOSH in an extremely positive direction," said Hurns.

In a written statement, CDC officials said the agency will begin the search for a new NIOSH director. Howard, who sent a letter to Leavitt in April expressing his desire to be reappointed, will take a short-term assignment as a senior advisor to help with the transition of World Trade Center activities to other officials.