People who breathe air polluted with large amounts of wildfire smoke visit hospital emergency rooms more often for respiratory symptoms, according to a Canadian emergency room physician and chair of the Global Climate and Health Alliance.

Rates of heart attack and cardiac arrest also increase after a couple of days of exposure, Dr. Courtney Howard said.

“So don’t just attribute that feeling of heaviness in your chest to asthma,” said Howard, who works in Yellowknife and is president of the Northwest Territories Medical Association.

“If you have other risk factors for cardiovascular disease especially, go see your friendly local emergency department.”