"Anybody breathing that stuff should be very concerned about what's getting into deep tissue, into the bloodstream," Carman said. "When you see that kind of smoke, it means you're getting a lot of unburned hydrocarbons. ... Those particles are loaded with carcinogens."
Officials ordered an evacuation of a wide area around the Husky Energy refinery to reduce the public's exposure to the plume. The fire Thursday was later put out, and residents were told they could return to their homes. But then authorities announced the evacuation order would remain and be re-evaluated throughout the night.