Powder prompts evacuation at Atlanta college

Cars and emergency vehicles line Clifton Road outside the Woodruff Health Sciences Center Administration Building.

ATLANTA, Georgia (CNN) -- Five office workers at Emory University were taken to a hospital Monday after one opened an envelope containing a powdery substance, college officials said.

All worked in the Woodruff Health Sciences Center Administration Building at Emory. They were under observation, but none was expected to be admitted, authorities said.

The incident was reported at 1:23 p.m. Monday, after a worker on the first floor of the building -- which houses offices for Emory's medical school -- opened an envelope containing an "unknown powdery substance," Emory spokesman Ron Sauder said.

"She began experiencing some sensations, including itching and difficulty breathing," Sauder said. "She reported to it the police. Subsequently, the administration building in which she works was evacuated and she was taken down the street to the university hospital."

FBI Special Agent Jeff Holmes, a spokesman for the bureau's Atlanta office, said the material has been turned over to the state Division of Public Health for testing.

About 100 people work in the four-story building. Officials with the DeKalb County Fire Department allowed the building to be fully reopened by 4 p.m.