wildfires

With wildfires causing air pollution in the GTA and across North America, is it safe to exercise outdoors? Professor Ira Jacobs offers his expert advice

The air in Toronto and across parts of North America has become so polluted due to forest fires in Quebec and Ontario that Environment Canada recently issued an air-quality advisory, suggesting people with asthma or heart disease, older adults and children wear a face mask when outside to reduce exposure to smoke particles. In response, many organizations have decided to reschedule outdoor activities or move them indoors.

Ira Jacobs

Ira Jacobs, a professor of exercise physiology in the University of Toronto's Faculty of Kinesiology & Physical Education and the director of the Tanenbaum Institute for Science in Sport, spoke with faculty writer Jelena Damjanovic about how everyday fitness and exercise routines can be modified to suit such conditions. Jacobs’ area of expertise includes physiological responses and adaptations to environmental extremes.

Should we exercise outside when the air is smoky from wildfires? What are the risks?

The short answer is no. The main issues of concern are the absolute amount and size of the particles in the air that are associated with both acute respiratory health risks, as well as accumulating increases in those risks with repeated exposures.

The other important aspect is our body’s ventilation rate – how much air is being drawn into our lungs. When it comes to the effects of the forest fires on our outdoor air quality during the last few days … the news is actually fairly bad. Reports indicate that over 90 percent of the air particulate content of forest fire smoke consists of very fine particles that are about less than 2.5 microns in size (about 40-50 times smaller than a grain of sand). The smaller the particulate size, the deeper down into our lungs that those particles can be drawn and deposited. And the deeper they go, the greater the pulmonary/respiratory health risks.

The health risks are compounded because most of us become primarily “mouth breathers” when we exercise, so some of the body’s natural particulate trapping and filtering mechanisms in the nasal cavity become ineffective at the high ventilation rates that we generate during exercise – at least 10 times the normal resting ventilation rates, and much higher for athletes who are training or competing.

What’s a good alternative?

Much of the problem is avoided – or significantly reduced – by exercising indoors, particularly in more recently constructed buildings that are well sealed and where the indoor air is recirculated and cooled as part of the recirculation process. Some large older buildings draw in outdoor air continuously and cool it after it has been drawn into the building – so given today's air-quality challenges, it’s good to know what the status of the air circulation is wherever you’re exercising indoors.

Even in this worst-case scenario, appropriate filters can be installed to trap the particulate matter of concern. In summary, for now and until the air quality index improves, exercise in a air-conditioned building or at home.

For those not easily dissuaded, are there any adjustments they can make to reduce the risks of exercising outdoors?

Reducing the duration of exercise at high ventilation rates will commensurately reduce the risk.

And wearing a respirator like a N95 that traps particulate matter that is less than 2.5 microns in size is also effective, but admittedly not very pleasant on a warm day. And some people find that a respirator or any face mask seriously impedes the ability to maintain the kind of exercise intensities that high-performance athletes need to maintain their training effects.

Wildfire smoke exposure during pregnancy may impact birth weight: Study

Christopher.Sorensen — Tue, 10 May 2022 17:08:53 +0000

Wildfire smoke exposure during pregnancy may impact birth weight: Study

Christopher.Sorensen Tue, 05/10/2022 - 13:08

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A study co-authored by U of T researcher Matthew Adams suggests that wildfire smoke in Brazil affected women in the first trimester of pregnancy, increasing the risk of low birth weight in full-term babies (photo by Carl De Souza/AFP via Getty Images)

Kristy Strauss

Topic

Breaking Research

Climate Change

Research & Innovation

U of T Mississauga

wildfires

Wildfires can decimate forests, destroy communities and fill the air with noxious smoke – but their impact may be even more far-reaching, affecting the health of babies in the womb.

A recent study co-authored by Matthew Adams of the University of Toronto Mississauga suggests that wildfire smoke can affect women in the first trimester of pregnancy, increasing the risk of low birth weight in full-term babies. Other studies have associated a low full-term birth weight with conditions later in life, including hypertension, low IQ, diabetes and heart disease.

Matthew Adams

Adams, an assistant professor in U of T Mississauga's department of geography, geomatics and environment, co-wrote the study with researchers from Brazil, Denmark and the U.S. Their paper appeared in The Lancet Regional Health Americas this spring.

The researchers conducted a statistical analysis based on wildfire records and birth data from Brazil, a wildfire hotspot responsible for an estimated 12 to 16 per cent of global, wildfire-related particulate emissions. The southern region of Brazil had the highest risk of low birth weight associated with wildfire exposure, with a nearly 19 per cent increase when the exposure happened in the first semester.

“Given that wildfire is a growing problem in several regions worldwide, especially in Brazil – a fire-prone region, the epidemiological evidence shown in our study should be of great concern to the public health community and policymakers,” the researchers say.

The researchers studied 1.6 million birth records from across Brazil between 2001 and 2018, and analyzed wildfire smoke that occurred throughout that timeframe.

They found that mothers who were exposed to wildfire smoke in their first trimester of pregnancy were more likely to have a baby born with a low birth weight – under 2,500 grams or roughly 5.5 pounds.

“I was surprised that the effect was so prevalent in the first trimester, but not in the second or third,” Adams says. “The thing we still don’t know is why. From a policy perspective, it doesn’t really matter why," he said. "We know the smoke is toxic, and we see this effect.”

He says the researchers were also surprised to find that some areas of Brazil had higher rates of low birth weight than others.

“We saw the effects changing across time and across space. We wondered: why do areas in the north of Brazil and the south of Brazil seem to have different effects? You would think it would be the same,” says Adams, who is the geographic information system (GIS) program director.

“I think this is important as we do more and more of these studies in different geographic regions, to recognize that the effects may change across space. That’s why it will be worthwhile to look at them geographically and across time.”

He adds that there has been previous research linking air pollution with low birth weight, but there are not many current studies about the association between wildfire smoke exposure and low birth weight.

Going forward, Adams says this may be an area of research that needs further study, especially as climate change creates drier conditions increasing the risk of wildfires in North America and elsewhere.

“The thing that’s interesting about particles in wildfire smoke is the toxicity can be different,” Adams says, adding that particles from wildfire smoke can include manufactured objects like metals and plastics that can release toxic components into the air.

“When you have wildfires associated with man-made structures, which is what we see in North America, we see these wildfires very often encroaching on communities and burning people’s homes. It’s not just burning the tree matter – you are burning lots of nasty compounds that are embedded in the structure of those man-made buildings.”

Adams says he would like to replicate the research in Canada, which is seeing more wildfires.

“With climate change, we are having these major wildfire events that maybe weren’t so common 20 or 30 years ago. I think it’s important for the Brazilian context, but I think it can really translate to a broader spatial scale for areas that have become more fire-prone,” he says.

Adams hopes his research will encourage policies that reduce exposure to air contaminants.

“We know a lot of the things we need to change,” Adams says. “But when we start thinking about climate-related aspects, and looking at the clock, we don't have an infinite amount of time to address many of these issues.”

Study of Fort McMurray homes after wildfire should give residents 'peace of mind': U of T researchers

Christopher.Sorensen — Tue, 15 Jan 2019 16:25:18 +0000

Study of Fort McMurray homes after wildfire should give residents 'peace of mind': U of T researchers

Christopher.Sorensen Tue, 01/15/2019 - 11:25

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The remains of a charred vehicle sit in a Fort McMurray, Alta., residential neighbourhood that was heavily damaged by a wildfire on May 7, 2016 (photo by Scott Olson via Getty Images)

Liz Do

Topic

Global Lens

Faculty of Applied Science & Engineering

Research & Innovation

wildfires

Despite devastating 2016 wildfires that turned skies grey and forced an evacuation of Fort McMurray, Alta., University of Toronto researchers have found no evidence of harmful levels of residual toxic substances in local homes.

Instead, their study of more than 60 homes in Fort McMurray found levels of contaminants comparable to homes across Canada.

The findings, which so far suggest no immediate health risks due to fire-ash exposure, were recently published in Geophysical Research Letters.

“That was the surprise – that even after this fire, we actually didn’t see higher levels of contaminants,” says Arthur Chan, an assistant professor in U of T’s Faculty of Applied Science & Engineering.

“The levels we saw were not terribly high. If we compare them to health guidelines – what is considered to be a health risk for soils – the results from samples we collected in the homes were generally lower.”

The large wildfire in May of 2016 forced a mandatory evacuation of more than 80,000 residents in the city and surrounding region, making it the largest recorded wildfire evacuation in Canadian history. As people slowly gained re-entry to their homes a month later, concerns were raised about residual fire ash and other toxic substances in homes that could pose health risks. Smoke and ash can contain a large number of potentially harmful carcinogens, including arsenic, heavy metals and polycyclic aromatic hydrocarbons (PAHs).

Chan and his research team visited Fort McMurray in the summer of 2017 to find out if there was indeed cause for concern.

“Many people were saying, ‘I’m not sure if it’s safe for my children to come back and live here after this big fire,’” Chan says.

Postdoctoral fellow Lukas Kohl and fellow researchers Meng Meng and Cynthia Jing vacuumed up dust from homes in Fort McMurray, looking for evidence of residual fire ash. To ensure representative coverage, the team chose neighbourhoods that suffered significant damage – where re-entry was delayed – as well as neighbourhoods less affected by the wildfire.

Postdoctoral researcher Lukas Kohl and student Cynthia Jing sampled homes in northern Alberta for ash left over from the 2016 wildfire (photo by Tyler Irving)

After analyzing dust collected in living rooms and bedrooms (the largest and most frequented areas in a home) for toxic substances such as PAHs, arsenic and heavy metals, the team reported that the levels, while detectable, were no higher than in Canadian homes that had not been affected by the fire.

For some chemicals, such as lead, levels were actually higher in Toronto homes than those in Fort McMurray.

“Since Fort McMurray is a newer city, a lot of the infrastructure like pipes and paint don’t contain lead,” says Chan.

Although the results surprised Chan’s team, he suspects the reason levels were normal has to do with residents’ cleaning habits.

“We think people are cleaning quite a bit after the fire,” he says. “A lot of the houses have gotten insurance companies to cover the cost of a cleaning crew. And even for houses that don’t have insurance clean-up, the residents have cleaned quite thoroughly, due to concerns about residuals from the fire.”

Chan's lab will continue to study samples collected from other areas of the home. They’ve also partnered with a pulmonary specialist at Toronto General Hospital, who is currently assessing the lung health of those who participated in his lab’s study.

Chan stresses there are other types of health concerns that can result from the fire, ranging from the mental health of victims to the occupational health of firefighters who battled the blaze.

But for this study in particular, he hopes the findings give the Fort McMurray community peace of mind.

“I think they should take this as good news,” he says. “So far, we don’t have any evidence to say that there are any immediate health risks in their homes due to the fire.”

In the aftermath of the Fort McMurray wildfire, U of T researchers look for toxins

ullahnor — Wed, 14 Jun 2017 18:46:02 +0000

In the aftermath of the Fort McMurray wildfire, U of T researchers look for toxins

ullahnor Wed, 06/14/2017 - 14:46

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Researchers with U of T's Faculty of Applied Science & Engineering will be looking at the ash left behind from the Fort McMurray wildfire (photo by Cole Burston/AFP/Getty Images)

Tyler Irving

Author legacy

Tyler Irving

Topic

City & Culture

Faculty of Applied Science & Engineering

wildfires

This summer, postdoctoral researcher Lukas Kohl and undergraduate student Cynthia Jing will be vacuuming strangers’ homes in northern Alberta. But they’re not there to clean – they are looking for evidence of long-term human health impacts arising from last summer’s devastating wildfire.

That fire, which raged through northern Alberta one year ago, is already estimated to be the most costly natural disaster in Canada’s history, destroying approximately 2,400 homes and forcing the evacuation of nearly 90,000 people. But the ash left behind by the fire can continue to affect people’s health long after the flames have gone out, says Assistant Professor Arthur Chan, the principal investigator on the project.

“Smoke and ash can contain a large number of different compounds, including organic compounds, heavy metals, black carbon and more,” says Chan. “Some of these are suspected to be carcinogens or are linked to other negative health outcomes.”

Postdoctoral researcher Lukas Kohl and undergraduate student Cynthia Jing will sample homes in northern Alberta for ash left over from last summer’s wildfire (photo by Tyler Irving)

Chan and his team use advanced analytical chemistry techniques to tease apart all the different components of the complex chemical mixtures, including fire ash. They can detect everything from heavy metals such as lead, a potential neurotoxin, to organic chemicals such as polycyclic aromatic hydrocarbons (PAHs), which have been associated with cancer.

“Of course, our hope is that we won’t find anything,” says Chan. “But if we do, we can inform people of their risk and suggest adjustments to their cleaning habits. We want to understand the impacts before people start to suffer from them and provide guidelines to minimize exposure.”

Read the Globe and Mail story

The team plans to collect house dust from dwellings in Fort McMurray, Alta. and other communities affected by the wildfire in the initiative – called Fire Ash Characterization and Evaluation of Toxicity (FACET). While much of the outdoor ash has been either shipped away from town or immobilized by spraying it with a glue-like substance known as tackifier, ash that has found its way into homes is a different story.

“This is the ash that is closest to people’s bodies and because we spend most of our time indoors, it would have the biggest impact on people’s health,” says Kohl. “Indoor pollution is not well understood so in a way this is a new perspective on forest fires.”

Dust collected using a wet, disposable cloth can be tested in the lab to see if it contains evidence of fire ash and/or elevated levels of toxic substances (photo by Tyler Irving)

Kohl and Jing will use a modified vacuum cleaner that collects dust in two small vials in the head of the device, before it has reached the mechanical components. They can also take samples by wiping surfaces with a wet, disposable cloth.

“We want to make sure we sample a variety of locations within the house,” says Kohl. “For example, we want to have one space that people clean often, like a living room, and one space that is not frequented, like an attic, where it is most likely we will find old dust that contains a lot of fire ashes.”

Initially, the team was concerned about the challenge of arranging house visits.

“When we’re sitting in Toronto, it can be hard to reach out to people who live hundreds of kilometres away,” says Kohl. But the response so far has been very positive.

“We have reached out to Facebook groups used by people in Fort McMurray, as well as local media,” says Jing. “Within two days, we already had more than 60 interested people contacting us about the study.”

The team plans to make three visits for each home – one in the summer, one in the fall and one in the winter – in order to minimize anomalies and compare any changes in hazard levels over time.

Can landscape design mitigate wildfires? U of T student says yes

lavende4 — Mon, 18 Jul 2016 15:19:33 +0000

Can landscape design mitigate wildfires? U of T student says yes

lavende4 Mon, 07/18/2016 - 11:19

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Aftermath of the Fort McMurray wildfire: what can landscape architects do to help mitigate wildfire disasters? (Jonathan Hayward/Getty Images)

Dale Duncan

Author legacy

Dale Duncan

Topic

Our Community

wildfires

Daniels Faculty of Architecture

landscape architecture

During a trip to Adelaide, Australia in 2015, Jordan Duke witnessed her first wildfire.

“We were driving over a hill and I could see a large plume of smoke in the horizon,” she said. “Thousands of hectares were on fire.” From the plane, the next day when she flew out, Duke was struck by the vast expanse of charred earth. She thought about it the entire flight home.

As a student in the Master of Landscape Architecture program at the John H. Daniels Faculty of Architecture, Landscape, and Design, Duke wondered: what could landscape architects do to help mitigate wildfire disasters? In the wake of the fire that struck Fort McMurray in Alberta in May, it’s a question that carries increased relevance — particularly since wildfires are predicted to increase in the future.

For her thesis project the following year, Duke researched how wildfires could be mitigated through tools that exist within the realm of landscape architecture. Her research culminated in the development of a strategy for Cleland Conservation Park. The park is based in South Australia where in February 2009, wildfires claimed over 170 lives. Her plan — which combined remote sensors embedded in the landscape with site-specific landscape design strategies that would produce both short- and long-term results — projected new possibilities, not only for the field of landscape architecture but also for how we could diminish such disasters in the future.

“There’s a lot of planning when it comes to wildfires in terms of where to build neighbourhoods, and there are many techniques to track and evaluate an area’s likelihood of burning, but I found that there were few systems in place to reduce the risk of a large wildfire occurring in the first place, “ says Duke.

Inspired by her work the previous summer at the Daniels Faculty’s Green Roof Innovation Testing Laboratory (gritlab), the first part of her strategy included embedding remote sensors within the landscape that would allow for real-time monitoring of data such as humidity, wind, temperature, vegetation density, and water availability — factors that contribute to the likelihood of a fire.

“At gritlab, we learned that sensor technology is cheap and easy to deploy. I had no computer engineering background, but by the end of the summer, we were installing sensors throughout the green roof, downloading data and doing analysis,” says Duke. “This triggered an idea: what if we could take these sensors and deploy them across a huge site to monitor variables that would let us know in advance when fires are likely to happen?”

Under Duke’s plan, data from the sensors would activate a variety of responses across the landscape. For example, on dry, hot days, weather modifiers installed along the ridges and valleys of the park would disperse mist across the site to increase humidity levels. Using the regular ocean breeze moving across the site, the modifiers would also scatter the seeds of fire-resistent cypress trees along the ridges of the landscape. Over time, the wall of trees that would eventually grow would become windbreaks that could help slow the pace of a fire.

Excess rainwater, which normally flows down the hills to the ocean during heavy rain, would be collected in reservoirs, which could become recreational pools for people visiting the park or sources of water for animals in search of refuge. When sensors indicate the risk of a fire in a particular location, however, the water would be released down the valley to soak the landscape below. The large amount of rapidly released water would also increase erosion runoff, thus creating firebreaks throughout the valley.

Duke also considered vegetation, which provides fuel for burning fires. Artificial watering holes strategically placed throughout the park would attract animals in times of drought. Native wallabies, kangaroos and other animals coming to the pools of water would then feed on nearby vegetation, reducing fuel for a potential fire.

“None of these devices eliminate risk,” says Duke. “Instead, they work to shift risk from large scale, catastrophic events to smaller, everyday risk levels.”

In addition to these and other tactics designed to mitigate risk, Duke explored ways to influence human behavior. The weather monitors along the ridge of the hill above the city, for example, could be programmed to light more brightly at night during periods of high-energy use.

“The idea is to change the collective consciousness of the local population by highlighting invisible phenomena and patterns that are contributing to climate change and wildfire occurrences,” says Duke. Energy consumption in the city of Adelaide is among the highest in Australia.

Jordan Duke (centre), with Dean Richard Sommer and Associate Professor Alissa North, Director of the Master of Architecture Landscape program, at the 2016 Graduation Awards Ceremony

While the scope of her thesis was to research and propose a new approach to mitigating wildfires, Duke does hope to one day build and test her project.

Her hope is that the strategy she devised will plant the seeds for ways that landscape architects can contribute to wildfire mitigation in the future.

“Developing science fiction scenarios are necessary,” says Duke. “Imagining what could be done is usually the first step towards something actually happening.”

Assistant Professor Liat Margolis was Duke’s thesis advisor. Duke received the American Society of Landscape Architects Certificate of Honor and the Canadian Society of Landscape Architects Student Award of Merit at this year’s graduation awards ceremony.