A suspicious substance that forced the evacuation of a Government of Canada building at McCowan Road and Town Centre Court in Scarborough has been deemed not dangerous or toxic, fire crews confirm.

A person who works in the building told 680 NEWS a black substance was discovered in the mail room on the 6th floor, prompting the evacuation.

“There was a black fluid that came within an envelope,” confirmed Toronto Fire captain David Eckerman. “We evacuated the entire building as the smell from this liquid started to permeate the building.”

We’ve done a lot of testing,” he added. “And the determination is that this is not a hazardous substance.”

The building houses a Revenue Canada and passport office, but Eckerman said it doesn’t appear that there were any nefarious intentions.

“It doesn’t appear that anything untoward was intended by the mailing of the envelope,” he said.

Toronto Fire says 40 people were put into isolation and were assessed as a precaution, but no injuries were reported.

CityNews has learned the suspicious substance was a liquid that came from Thailand.

“We don’t know what it is,” Eckerman said. “But I’ll say we do know what it isn’t.”