This is what wildfire smoke is doing to your body (We asked a doctor)

This is what wildfire smoke is doing to your body (We asked a doctor)
Top Stories
The following is a fictional scenario used to illustrate some of the potential symptoms associated with exposure to severe wildfire smoke, and to describe the physiology associated with these symptoms. The medical descriptions here have been made in collaboration with and checked by Dr. Chris Carlsten, Professor and Head of the Respiratory Medicine Division at the University of British Columbia, at Vancouver Coastal Health.

Before getting out of bed, Robin smiles at the ease she feels in her back and leg muscles.

They’ve been working hard for her lately. Her muscles ached for a couple of hours after her second COVID vaccine last week. And for four months before that, she’s been training for a marathon. Her first marathon — date to be determined.

When she wakes up at 6 a.m. for another run after two rest days, and looks out her apartment window at the park below, it takes her a second to notice anything different. The sky isn’t a clear blue backdrop to the sun’s piercing rays. Instead, the sun’s light is diffused across a thick orange smog. The sun itself is an orange ball, the way it looks in previews for movies with cowboys riding off into sunsets.

Somewhere in the back of her mind she hears her mom’s voice explaining that pollution is the reason why the sunsets took on a dramatic, hazy quality through the smokestacks in the industrial town where they grew up. She doesn’t think yet about climate change, or about the wildfires blazing across Canada that are the reason for this smoky spectre over the city.

For now, it’s morning — running time — and Robin is focused. The orange sky, after all, is beautiful. She takes a picture on her phone, then laces up her shoes.

She steps outside and takes a breath.

What she breathes in is mostly the normal gases found in air, a combination of oxygen, nitrogen, and others. But today she’s also breathing in wildfire smoke, which contains a cocktail of things that aren’t normal, and could be irritating. These products of combustion include gaseous chemicals as well as small, solid particles from the trees or other types of fuel that were burned.

As she begins to walk down the sidewalk all she notices is the vague smell of campfire.

Her plan is to run a 5-kilometre loop this morning, and the first one is as easy and freeing as she first hoped when she felt her non-aching muscles this morning.


Along with her runners hitting the pavement comes a familiar, but annoying sensation.

Her eyes start to water, the way they did in April when the pollen was out in full force. She feels a burn in her throat when she takes a breath, which takes more effort than usual. She powers through.

The gaseous chemicals and particles contained in the wildfire smoke are beginning to irritate Robin.

Dr. Chris Carlsten explains that, except for her skin, the parts of Robin’s body that meets the outside world are covered in a mucous membrane — a waterlike liquid substance that acts as a buffer between exposed areas. like the nose, eyes, and throat, and the outside world.

And the mucous membranes don’t like to be confronted with potentially damaging substances.

Part of what happens in Robin’s body is a mechanical response, Carlsten says. Those membranes cover sensitive tissues full of nerve endings. So when the nerves in Robin’s eyes detect the presence of a tiny particle, they trigger a mechanical response for Robin to blink — to try to rid her eye of the intruder.


The other thing that happens is chemical. Fire smoke is typically acidic, with pH often less than three and so can cause a burning sensation. Her eyes tear in response, her throat feels more rough — and her nose starts to run.

By the time she gets back to her apartment, Robin is rubbing her eyes and nose. The smoke has also come into contact with her lungs. She lets out a few coughs.

OK, so it wasn’t a good run. Sometimes it’s just not. She’s still not thinking about wildfire, or about climate change.

Back inside

By the time Robin has showered, poured a cup of coffee, and sat down at her work-from-home desk to read the news her cough is gone, and her eyes feel normal.

People, Carlsten said, are typically resilient to short-term wildfire smoke exposure. If they are removed from the environment, they will generally feel better.

That’s when Robin sees the headlines. Forest fires have created a severe air quality problem in her city. Even though her city is far away from the fires, the wind has carried unhealthy particles to the city.

This summer, plumes of smoke from blazes across British Columbia and northern Ontario have covered much of the country in a haze that has blanketed Toronto and even reached New Brunswick.

Robin lets that sink in for a moment.

She checks the air quality forecast and sees it’s at 7 on the Air Quality Index, a reading that makes the air unhealthy for sensitive groups like seniors, and people with asthma, and at which it’s recommended people exercise indoors instead of outdoors. It’s a scale out of 10, with anything below three considered low risk for outside activities.

Some regions in Canada have recently hit a 10, at which point experts recommend that seniors, children and pregnant women, as well as anyone with respiratory or cardiovascular conditions stay inside or at least limit strenuous activity outside.

She wonders if, like the COVID-19 pandemic, the smoky air will soon keep people in their homes more often.

During the work day, Robin doesn’t think too much about the air outside. By the time she’s done working at 5:30, she actually realizes she’s likely going to be late to meet friends at a patio about five kilometres away.

She hasn’t forgotten the painful experience of running this morning, and she does stop to consider the air quality reading she checked this morning. It had said “unhealthy for vulnerable groups.” Robin doesn’t feel like this applies to her. She’s 37 and planning to run a marathon. She hops on her bike to head to the restaurant.

Now she’s peddling hard, to make up for the late hour, and to get up a hill on her route to the restaurant.


She breathes deep and can taste the smoke in the air on her tongue. She thinks about what she might say to her friends once she gets to the restaurant — that it feels like she peddled right through the consequences of climate change to get there, that the impacts of a warming planet they had been forewarned about for decades were undoubtedly here.

Then she stops thinking about her friends. One, big breath pushed her over an edge. Before she knows it, she’s coughing uncontrollably. She swerves off the road, stashes her bike, and tries to take a deep breath between coughs. But it feels strained.

Now that she’s exerting herself even more than this morning, the smoke is causing something called oxidative stress. It’s a chemical reaction that can damage cells in Robin’s body. As a result, her airway is becoming inflamed.
Read more on Toronto Star
News Topics :
As smoke from wildfire on the west coast of the United States continues to make its way across the country, many Canadians are finding it harder and harder to breath....
SAN FRANCISCO Northern Californians were confronted with multiple threats as wildfires, unhealthy smoky air, extreme heat, the looming possibility of power outages and an ongoing pandemic forced many to...
CANBERRA, Australia Fire alarms have been sounding in high rise buildings across downtown Sydney and Melbourne as dense smoke from distant wildfires confuse electronic sensors. Modern government office blocks in...
Top Stories
Smoke from forest fires in northwestern Ontario made its way to the GTA on Monday, prompting a warning from Environment Canada about poor air quality and reduced visibility. Environment Canada...
Top Stories
Smoke from forest fires in British Columbia continues to roll into the Prairies, affecting everyone from infants to athletes — not to forget the wildlife. On Wednesday, Edmonton’s High Level...