The report states that controlled fire is seen as a tool to mitigate some of the harm.
When the Perins Peak Fire broke out west of Durango on May 24, a thick cloud of brown smoke blotted out the sun.
When the Durangos inhaled, they inhaled poisonous smoke.
Research has shown that wildfires have serious health consequences, leading to cancer, respiratory illness and even premature death. Public health officials and medical groups say that as climate change exacerbates wildfires, human health risks in southwestern Colorado will only increase.
But even as they express concern about the health impacts of wildfires, a new report from the American Lung Association suggests a solution may already be found.
“We know that climate change makes it more likely that we will have stronger and more frequent wildfires,” said Nick Torres, director of advocacy for the American Lung Association’s Colorado office. “If we do nothing, it will not benefit public health when it comes to the health effects of wildfire smoke. We recognize that prescribed burning can be a useful tool to address this increasingly pressing issue as we see more and more wildfires.”
Because forest fires burn forests, they create three significant sources of air pollution.
The first is large particulate matter, also known as PM10. A PM10 of 10 micrometers or less is approximately one-fifth the width of a human hair.
Large particulate matter from wildfires exacerbates respiratory illness and often irritates the nose, throat and lungs, and can trigger sensitive groups such as asthma and people with COPD, said Dr. Afif El-Hassan, a California pediatrician and former member of the board. on the Board of Governors of the California American Lung Association.
Often associated with industrial pollution, ozone is also a by-product of wildfires.
“Ozone causes what appears to be sunburn inside the lungs. It is very irritating and causes an inflammatory response,” El-Hassan said.
But the most dangerous air pollutant that wildfires produce is fine particulate matter, or PM2.5.
The health risk that PM2.5 poses is a direct result of its size; at 2.5 micrometers or less, PM2.5 is approximately 1/25 the width of a human hair.
“Because they’re smaller, you can inhale them deeper into your lungs,” said Brian Devine, director of environmental health at the San Juan Public Health Basin. “They represent the biggest health problems for most people.”
Deep in the lungs, small solid particles can penetrate the body’s defenses and even enter the bloodstream.
In the short term, PM2.5 exposure has been associated with increased asthma attacks, hospitalizations for heart and lung disease, and premature death. Research has linked long-term exposure to PM2.5 to heart and lung disease and even cancer.
A 2015 review by the International Agency for Research on Cancer concluded that fine particulate matter is the cause of lung cancer.
But particulate matter and ozone pollution from burning trees is only part of the wildfire smoke puzzle.
As wildfires burn communities in southwestern Colorado, they consume forests as well as buildings, vehicles, and propane tanks, all of which release toxic chemicals that can then be inhaled with wildfire smoke.
2021 study published in a peer-reviewed journal Connection with nature found that fine particulate matter from wildfires was 10 times more toxic than pollution from industrial sources.
Unlike pollution from cars or power plants, which is regulated, wildfires release whatever they burn.
“The particles themselves can be made up of several chemicals and particles that are basically poisons in the body,” El-Hassan said. “When something gets past the defenses of the lungs, you basically get a dose of the carcinogen into the bloodstream through the lungs.”
“It could be something quite poisonous,” he said.
One 2012 study published in Environmental health perspectives an estimated 339,000 people die worldwide each year due to the effects of wildfires.
Climate change could worsen the health effects of wildfires in southwestern Colorado, and that’s something Devine is worried about.
“We think it is quite clear that this is one of several environmental health impacts that will be exacerbated by global climate change,” he said. “We know the western United States will be drier and we have a lot of forests that haven’t burned at normal intervals and are drying up. The result of this will be hotter fires, bigger fires and more impact on air quality.”
Along with more frequent and larger fires, scientists predict increased drought in the southwest.
The drought will exacerbate the detrimental effects of wildfires, El-Hassan said, not only helping to fuel more fires but also reducing rainfall, which purifies the air.
As residents of Southwestern Colorado face increasing health risks from wildfires, they may also have an immediate solution that benefits both wildfire mitigation and residents’ health.
On June 8, the American Lung Association released a report examining the potential for prescribed fires to mitigate the health effects of wildfires.
While research that directly contrasts the two is limited, the report concluded that new evidence suggests that prescribed fires have less of an impact on air quality and health.
Scheduled fires often burn at a lower intensity for a shorter time than wildfires. Fire brigades also plan for burns to limit their impact on air quality and carry them out on days with higher humidity and more predictable conditions.
Both reduce potential exposure to harmful wildfire smoke.
But the biggest benefit of assigned burns is control. Crews can more readily direct prescribed burns, directing them away from things like houses and propane tanks and reducing the amount of toxins fires release in the smoke.
“Given the alternative to uncontrolled wildfires, of course the preference would be to place more emphasis on prescribed burns as a tool to mitigate negative air quality (and) health impacts,” Torres said.
While the American Lung Association highlights the potential of prescribed fires, its report notes that more research needs to be done by scientists to compare the two and come to conclusions that could be useful for public health and land management.
As public health advocates and scientists begin to explore the benefits of prescribed fire, there are steps southwestern Colorado residents can take to reduce the risk of wildfires.
On days with heavy smoke, El Hassan and Torres suggested that people stay at home and try to close their homes as much as possible.
But wildfire smoke precautions can also be more subtle.
Forest fires are usually diurnal, with smoke sinking closer to the ground at night and rising as the air mixes during the day. Air quality is often worst in the early evening and at night, and best at noon, Devine said.
“It is likely that at certain levels of air quality you can safely go for a walk, but you may not be actively exercising,” he said. “You may need to reduce the amount of intense exercise, rather than stop it entirely.”
New research also shows that for many people, indoor air can be just as bad, as fine particulate matter from wildfire smoke can enter their homes.
“At certain levels of air quality, when we become ‘very unhealthy’ and ‘dangerous’, we begin to share messages in the public health community about not only staying indoors, but about actually filtering indoor air,” — Devine. said.
Those who are concerned about the health effects of smoke can always use N95 masks, he said, although they should fit snugly to keep small particles out.
With a rosy outlook for southwest Colorado, awareness and action will be key to addressing the health effects of wildfires.
“We know we can create very specific short-term spikes in unhealthy air from wildfires, so we’re trying to focus on how the public can be better informed,” Torres said.