The University of Toronto has closed two labs in its Medical Sciences Building as a precaution after finding dust containing asbestos fibres during renovations.

“We’re on this. The full team is engaged,” said Scott Mabury, U of T’s vice-president of operations.

One instance of dust samples containing the asbestos was found Feb. 1 in a faculty research lab and a second on Feb. 24.

Both are related to remediation work taking place in the building, located on the St. George Campus, according to Mabury.

A third instance, not connected to the remediation work, was discovered Sunday.

The asbestos was found during major renovations in the building, part of a $190-million project to improve labs across the university’s campuses.

Since November, the university has been removing asbestos from seven locations on the third, sixth and seventh floors of the Medical Sciences Building.

“Dust was observed in locations where we didn’t expect it, and we tested that dust,” said Mabury. “We’ve tested lots of dust samples and only a handful, a few have tested positive.”

He said asbestos is “common on campus,” having been applied to many buildings built after the Second World War until the 1980s. The university has a policy to remove asbestos from any room undergoing significant renovation.

“The key is to not disturb it. We only disturb it when we are removing it,” he said. “We have a large number of buildings that have asbestos and so we are methodically, on our own initiative, removing that on a project-by-project basis.”

He said there is no danger to students and staff who continue to use the classrooms and public spaces in the building, which otherwise remains open.

“We don’t like any examples where dust is found with asbestos, but the most important thing is (that) air is the route for hazardous exposure,” said Mabury, a chemistry professor. “We’ve done 243 air samples and we’re doing roughly 20 more per day to ensure the air in the medical sciences building is below any kind of regulatory limits.”