HILLSBORO, Ill. (WCIA) — An unknown substance that caused a scare at a state prison in Hillsboro on Wednesday was determined to be non-hazardous, officials with the Illinois Department of Corrections said on Thursday.

Naomi Puzzello, Public Information Officer for IDOC, said preliminary tests performed on the substance found at Graham Correctional Center came back negative for narcotics or hazardous materials. The substance was ultimately determined to be baby powder.

Puzzello said the powder should not have necessitated the use of Narcan or require hospitalization, but IDOC acted out of an abundance of caution when some prison staff members reported feeling dizzy. No inmates incarcerated at the prison were hospitalized.

“IDOC works diligently to ensure the safety of both incarcerated individuals and employees and worked swiftly to ensure everyone had access to the care they requested,” Puzzello said.

All of the staff members who went to the hospital have been discharged.