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Wildfire Smoke Is Making Us Sick

Mask up, scrub the air and head to a clean-air shelter. Don’t ignore the hazy skies, say experts.

Michelle Gamage 9 Jun 2023The Tyee

Michelle Gamage is The Tyee’s health reporter. This reporting beat is made possible by the Local Journalism Initiative.

It’s early June and there are 80 wildfires burning in the province, according to the BC Wildfire Service dashboard.

There are evacuation orders in place for areas of the Peace River Regional District, and localities close to significant fires are blanketed in smoke.

Fires are also bringing hazy skies to Vancouver and other areas of the province farther away from active fires. Across the continent, smoke is coating Toronto and New York right now.

While smoky days and even weeks might be a regular feature of future Canadian summers, they’re not something we should be complacent with, according to health experts.

Wildfires burn everything in their way, says Dr. Melissa Lem, president of Canadian Association of Physicians for the Environment. That includes human-built infrastructure like houses and cars, which release toxic pollutants.

When we breathe smoke, we’re breathing in fine particulate matter, which means we’re breathing in particles that are smaller than 2.5 micrometres in diameter — about one-eighth the width of a human hair.

The smaller the particle, the deeper it can get in your lungs when you inhale.

Metro Vancouver issues air quality warnings when there are more than 25 micrograms of fine particulate matter in one cubic metre, says Geoff Doerksen, program manager for the Air Quality Advisory Program for Metro Vancouver.

On a normal, non-smoky day there are generally around 10 micrograms per cubic metre in Vancouver, he says. During smoky days it’s closer to 100.

There have been smoke advisories issued in Metro Vancouver in six of the last eight summers, with 2022 and 2018 seeing the most advisory days with 22 advisories each, Doerksen says.

“Before 2015 it was rare to experience wildfire smoke in Metro Vancouver and when we did the effects on air quality were mild,” he says.

Then, on July 5, 2015, the sky was stained a hazy orange for the first time and pieces of ash gently fell, like gauzy summer snowflakes. The impacts of wildfires had arrived in the Lower Mainland.

During smoke events Lem says she sees a spike in patients with respiratory issues, such as wheezing, coughing, runny noses and headaches, and patients worried about their mental health, reporting anxiety and depression.

Smoke events also cause a spike in cardiovascular problems, but those patients go to the ER, not her clinic, she adds.

Because it’s so small, Lem says fine particulate matter can get into your bloodstream and build up in red blood cells, which damages the cell — and can even kill it.

Smoke causes inflammation in many different body systems, including your lungs and your brain, she says.

“There’s no system in the long run I can imagine wildfire smoke would not be bad news for,” she adds. “It’s really important to protect ourselves.”

Lem and Noah Quastel, director of law and policy, healthy indoor environments with BC Lung Foundation, say the studies on long-term health impacts of exposure to wildfire smoke are sparse because we haven’t been having smoky summers for that long.

“We’re all part of a big experiment right now,” Lem says.

Lem points to research from Montana, that tracked how wildfire smoke exposure impacted people’s breathing two years after their exposure, and to research from The Lancet, which found long-term exposure to wildfires may increase Canadian’s risk of developing lung cancer and brain tumors.

We also know exposure to the pollutants in wildfire smoke can lead to cardiovascular and lung disease, Quastel says.

When smoke rolls into town, public health messaging emphasizes individual action and encourages people to stay indoors, use air cleaners, be aware of the air quality health index or wear an N95 mask, Quastel says.

That’s all good advice, but can come with some caveats, he adds.

Wildfire smoke can happen during extreme heat events, and when that happens you need to make sure you won’t overheat if you close the windows, he says.

“Wildfire smoke will make you uncomfortable and chronic exposure isn’t good for your health, but not overheating is the most important,” Quastel says.

It’s possible to not realize you’re overheating, he says. During heat events make sure to monitor your temperature, take cold showers, visit a cooling shelter and check in on elderly folks and other people you know who may struggle to keep cool.

Closing your windows when its smoky outside mostly works when you’ve got an indoor air purifier, Quastel says, adding that indoor air pollution comes from gas stoves, solvents and even furniture.

Lem adds if you’ve closed your windows you should also avoid burning candles or vacuuming.

Ideally an indoor space would be cooled and have its air cleaned by a HVAC system, Quastel says. Portable air cleaners should be rated MERV 13 or higher, or have a HEPA rating.

Portable air filters start around $200 and that’s a cost you should save up and budget for if possible, Quastel says, especially considering how future summers are very likely to be smoky.

“One in five British Columbians have a lung condition and they’ll be more affected by the smoke,” he says, adding he has asthma and breathes better at home when he sets up his filter close to where he’s sitting or sleeping.

You can also build your own air filter. The BC Centre for Disease Control recommends buying an air filter from a store but also put out guidelines on how to build an at-home air filter. The Tyee also recently wrote about the DIY air filters we use in-office, which were built with MERV 13 filters.

Another low-cost solution is to wear an N95 mask, which are sold for around $3 each. When worn properly an N95 mask can reduce the amount of fine particulate matter you breathe by 90 per cent, according to the BCCDC.

Quastel says wearing a N95 while commuting to work is a good idea.

Finally, spend time wherever the best air quality is, if you have the flexibility to make that choice. “If the office has good filtration, you’re better off going there or going to clean air centre than staying home where you can’t clean the air,” he says.

Lem recommends people also keep their prescriptions up to date so that, for example, someone with asthma has their inhaler ready to go when smoky skies appear.

But the most bang-for-your-buck clean-air solution would be to “do everything we can to end our dependance on fossil fuels so we stop driving climate change, which is creating wildfires and exposing us to smoke in the first place,” she says.

Quastel agrees, noting how current health messaging that focuses on individual action is a “stop-gap measure” and more needs to be done to improve ambient air pollution and to avoid wildfires through proactive climate action.

B.C. could also follow Washington state and Oregon’s lead, and help low-income folks buy home air conditioning units, Lem says, adding B.C. could go further and help low-income folks buy machines that cool and clean the air.

When asked when B.C. could see a program like that, Health Minister Adrian Dix didn’t directly answer the question but told The Tyee there has been “substantial” investments in indoor air quality in long-term care facilities and schools. The province will be publishing a report on the impacts of at-home air conditioners soon, he adds.  [Tyee]

Read more: Health, Environment

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