According to the Salt Lake City Fire Department, the envelope was opened on the third floor of the building shortly after 10 a.m.
Six people were close to the powder, but none showed any symptoms upon evaluation. All six were released to go home and none required hospitalization.
Part of the third floor was evacuated as the haz-mat crews found and removed the white powder. The powder was taken to the state crime lab, a statement from the Salt Lake City Fire Department said.
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