A person wears a mask as they walk along the Rideau Canal in Ottawa on June 7. Forest fire smoke continues to shroud the nation's capital, triggering air quality advisories.Sean Kilpatrick/The Canadian Press
Anyone living in areas affected by poor air quality faces potential health risks from breathing in wildfire smoke, according to experts who urge people to take precautions until conditions improve.
And as Canada faces what could be the worst wildfire season in its history, there are growing concerns about how to grapple with the long-term health impact of worsening air quality.
Across parts of Southern and Eastern Ontario on Wednesday, outdoor recreational activities and recesses were cancelled and some hospitals saw a small uptick in people experiencing shortness of breath and other symptoms as smoke from faraway forest fires made the air increasingly hazardous to breathe.
“These levels are so high that really everybody is at risk to some extent,” said Tom Kovesi, a pediatric respirologist at CHEO in Ottawa. “Even if you have no underlying health conditions, being exposed to this level can cause lung irritation, coughing, shortness of breath.”
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Smoke from wildfires burning in Quebec blanket Ontario, northeastern U.S.
The high levels of pollution in the air prompted Environment Canada to issue a special air quality statement on Wednesday, warning that smoke can have an impact on health “even at low concentrations.” Poor air quality is expected to continue into the weekend.
Some groups face higher health risks than others: people with asthma, chronic obstructive pulmonary disease and other lung problems; people who are pregnant; children; and individuals with other underlying medical conditions.
Even people who don’t face an increased risk may experience challenges breathing when the air quality reaches dangerous levels, experts say. Michael Fitzpatrick, a respirologist and chief of staff of the Kingston Health Sciences Centre, said many symptoms, such as an increase in coughing or a scratchy throat, will likely resolve themselves and not cause any permanent damage.
Smoky air hangs over the Toronto skyline, as seen from the CN Tower, on June 6.CARLOS OSORIO/Reuters
But wildfire smoke also contains high levels of fine particulate matter that can be absorbed into the bloodstream, causing inflammation.
“Those microparticulates can get absorbed into the blood via the lungs. There’s less known about the long-term effects of exposure,” said Anna Gunz, a professor at Western University’s Schulich School of Medicine and Dentistry and a pediatric intensive care doctor at the Children’s Hospital at London Health Sciences Centre. “People might not necessarily be aware,” she said.
For instance, there’s research indicating that particulate matter from wildfires can increase the risk of heart attack, stroke and other cardiovascular events, Dr. Kovesi said.
Experts advise higher-risk individuals to take immediate steps to protect themselves when the risk level of the air quality health index increases. According to the index, levels of 4 to 6 are considered moderate risk and vulnerable individuals are urged to reduce or reschedule outdoor activities. Levels of 7 to 10 are considered high risk and anything above 10 is considered very high risk.
Parts of Ontario, including Hamilton and Ottawa, were above 10 on Wednesday, although smoke affected millions living in the Greater Toronto Area and beyond.
There are several ways people can protect themselves when the air quality health risks go up. Staying inside with doors and windows closed and using an air filter can reduce inhalation of fine particulate matter. If no air filter is available, an air conditioner can also be used to reduce some of the fine particles in the air. If people have to spend time outside, such as those who work outdoors, high-quality masks can help.
Dr. Kovesi said he hopes the air quality improves in the next few days. But, as wildfires and other climate-related disasters become more common, it’s imperative for Canada to do more to protect the planet and reduce the health consequences of climate change, he said.
“As a lung specialist, you don’t start off your life being very political, but this is a political and a societal issue,” he said.