Topeka ? The powdery substance that sent six U.S. Postal Service workers to the hospital was identified early Sunday as toluene, a toxic solvent.

The Topeka Fire Department said in a statement that toluene often was used as a cleaning agent, and officials did not believe there was any “malicious intent” involved in the incident.

Emergency responders went to a mail-sorting center in Topeka about 4:30 p.m. Saturday after employees called complaining of scratchy throats and burning eyes after a powdery substance fell out of an envelope.

Six people working in the area where the substance was found were decontaminated and taken to St. Francis Health Center, where they were treated and released, said Kim Gronniger, a hospital spokeswoman. She said two of the workers transported to the hospital had complained of scratchy throats at the postal facility.

The powder was tested at the postal facility early Sunday by the Civil Support Team, a unit of the Kansas National Guard.

Inhalation or contact with toluene may irritate or burn skin and eyes, according to the Emergency Response Guidebook.