Friday, May 31st 2019, 10:08 am - Even when wildfires are successfully contained, long dry periods could mean extended periods of poor air quality due to wood smoke.
Much of Canada’s enormous territory is blanketed in forests -- a boon for natural beauty, a potential hazard during the warmer months when temperatures soar and rain is infrequent.
Whether started by lightning or natural causes, wildfires can quickly burn out of control, triggering evacuations and sending firefighters scrambling to contain them before they can threaten communities. In one example of how bad a wildfire crisis can get, the 2016 Fort McMurray wildfire burned more than 3,000 buildings and forced more than 80,000 people from their homes.
Even when wildfires are successfully contained, however, long dry periods could mean extended periods of poor air quality due to wood smoke, triggering warnings from the authorities -- but though it may coincide with seasonal allergens already in the air, can wood smoke make seasonal allergies worse in chronic sufferers?
Dr. Christopher Carlsten, the head of the University of British Columbia’s Respiratory Medicine Division, told The Weather Network that’s a hard question to answer.
Carlsten says researchers do know that pollution from everyday traffic can exacerbate the effect of allergens on sufferers, but at the moment, there’s been little research on whether wood smoke can have the same effect.
“Wood smoke is different from traffic pollution, but it’s similar enough that we’re concerned that it will do similar things, but that has not been studied in detail,” Carlsten says. “Regardless, it’s not likely to be the same as the allergen alone, it’s likely to be a different effect with the combination, assuming that it’s similar to what we’ve noticed with traffic plus allergens.”
Carlsten says wood smoke is different in composition from traffic emissions, being made up of mostly carbon and hydrocarbons, meaning its effects on allergies can’t be assumed to be same.
As well, burning wood doesn’t combust as efficiently as gasoline, so individual particles are larger. Particles in traffic pollution are small enough to be taken deep into the lungs, while wood smoke particles are likelier to be filtered out by the sinuses.
Image: Fort McMurray wildfire. Image sent into The Weather Network by Andrew Coish on May 10, 2016.
“The overall conclusion so far has been that wood smoke seems generally similar in terms of its effects on airway health, but if anything, somewhat less toxic than traffic,” he says. “It really depends on the end point, so it’s hard to reach a high-level universal conclusion.”
Still, smoky skies aren’t ideal, and Carlsten says there are steps people can take to protect themselves from smoke’s worst effects, not too dissimilar from how people can avoid exposure to outdoor allergens.
“I think avoidance is always good if possible,” Carlsten says. “On days of heavy smoke, those are good days to stay indoors or, if you’re outdoors, moderate your activity level so that you don’t take in more particles than you need to.”