About 189 litres of formalin, a chemical used for preserving tissue in medical laboratories, was inadvertently spilled Thursday afternoon, prompting the evacuation of about 500 people from the Thorlakson Building at the Health Sciences Centre complex.
The spill occurred when the main feeder tube in a laboratory area was accidently broken.
Emergency crews, including the Winnipeg Fire Paramedic Service's hazardous-materials unit, were called to the building at 820 Sherbrook St. about 1:30 p.m.
There were no injuries. A construction worker was briefly exposed to the chemical but was decontaminated by showering.
The Thorlakson Building, also called the Medical Services Building, has eight floors, including three floors of laboratory space.
Officials at a late-afternoon news conference said the construction worker might have leaned on a pipe on the fourth floor and it broke.
WFPS platoon chief Ted Kuryluk said it was expected the building would be closed a few hours, possibly into the evening, while fire crews cleaned up the spill and the area was restored.
Dana Erickson, the chief operating officer of Health Sciences Centre, said five adult elective surgeries scheduled for Thursday and six angiography cases scheduled for today were cancelled and will be rescheduled as soon as possible. He said no children's surgeries were cancelled.
"The emergency department has been impacted somewhat because of the interruption to lab services, and as a result, waits might be a little longer in our adult and children's emergency departments," Erickson said.
"I'm very glad to hear that it could only be a few hours before we're back in business. So from 1:30 to the evening sometime is welcome news."
Contingency plans for emergency lab testing to use the local lab network were in place and ambulances were rerouted Thursday evening.
Erickson said eight adult patients were moved out of the building -- four were sent home, two were moved to beds in another area of the hospital and two remained in recovery -- and six babies were moved to a nursery in the women's hospital.
Jim Slater, the chief executive officer for Diagnostic Services Manitoba, said the formalin used in the building's laboratories is a 10 per cent concentration that carries less risk of being flammable than in a higher concentration. It is an irritant to the eyes, nose and throat of anyone exposed.
Slater said contingency plans are in place for emergency lab testing in other local labs during the cleanup.
Kuryluk said the fire department's response time was "quite quick" because personnel were already at HSC at the time of the spill.
"We had a number of crews at the hospital on a visitation tour with the new building and all the construction," Kuryluk said. "The department was being proactive."
He said six Winnipeg Transit buses were immediately brought to the area to provide shelter for staff or patients. The buses were not needed after those affected were relocated.
Several roadways in the HSC area were closed, causing numerous traffic tie-ups, but were reopened about four hours after the incident.