As U.S. wildfire seasons escalate in length and intensity, firefighters and residents in western states face mounting threats to their long-term health due to prolonged exposure to smoke.

The problem is that we don’t know much about what it does to human bodies, raising concerns for vulnerable people, like children, older people, and those with respiratory and cardiovascular problems.

Wildland firefighters are also exposed to extremely high levels of smoke for months at a time.

In our modern, high-tech world, Americans have access to troves of live data showing air quality levels in just about any location in the country and the associated risk factors. People in cities and rural environments can look at that data to make an informed choice about going outside.

But there’s a major problem with this approach. The Air Quality Index, a tool created by the Environmental Protection Agency, was created using decades of research into the health effects of urban air pollution, not wildfire smoke.

While urban air pollution has improved drastically since before the 1970s, owing to the passing of the Clean Air Act in 1963 and major additions in subsequent decades, wildfire smoke is different. It raises important questions about how wildfires affect our health and what short—and long-term — damage they could do.

Urban air pollution, mainly from vehicles and industry, contains nitrogen oxides (NOx), sulfur dioxide (SO2), and fossil-fuel particulate matter like black carbon. Wildfire smoke, however, is rich in organic particulate matter and volatile organic compounds (VOCs) like acrolein and formaldehyde, with lower levels of NOx and SO2.

According to EPA studies, emerging research suggests that wildfire smoke may lead to different short-term health outcomes than urban pollution. However, researching the differences over long periods is not easy.

Reckon spoke with Prof. Matthew Strickland, chair of the Department of Epidemiology, Biostatistics, and Environmental Health at the University of Nevada, Reno, to learn more.

Reckon:

What do we know about the health effects of urban air pollution on humans compared to wildfire smoke?

Prof. Strickland:

There are concerns and questions about wildfire smoke being very different from urban air pollution. The chemistry, epidemiology, and some of the toxicology studies that have come out show that it’s different and has different health outcomes.

The research supporting the Air Quality Index is not really specific to wildfire smoke.

Multiple studies have provided at least preliminary evidence that wildfire smoke might be more harmful to respiratory conditions like asthma and COPD than typical urban air pollution mixes and perhaps less consequential for cardiovascular disease. Those are open research questions.

Heart attacks seem less strongly associated with wildfire smoke than urban air pollution.

It’s just different.

We know urban air pollution harms children and can send them on a different health trajectory into adulthood. What are the long-term effects of wildfire smoke on them?

That’s a tricky question because it’s challenging to study children who live in neighborhoods with relatively high air pollution and children who live in parts of the country where there’s a lot of wildfire smoke during a sensitive period of their development.

We know these examples exist. Questions about what it means for their lives when they’re 30 or 40 years old are fascinating and not impossible to answer. However, they’re challenging because of the long follow-up times and obtaining health information over decades. I think it’s an important question, but one that is really pushing the limits of what we can do. I think it’s aspirational at some level.

Kids are physically smaller, so their airways are not as large. If you have inflammation or something caused by air pollution, it blocks more of the airway. That means kids could end up with more immediate problems from wildfire smoke. But in the long term, it’s not easy to know.

Why are we not doing these studies?

I can’t apply for a National Institute of Health grant for a 30-year study right now. That’s just not how it works. The institute typically grants studies in five-year periods. There may be exceptions for some, but it’s not normal.

If you do a good job, gather interesting data, write compelling grant proposals, and convince them to give you money to follow the people for another five years, that’s great. We see examples of that in the literature, but there are no guarantees and scientific priorities eventually shift, making it harder to get the grant repeatedly over long periods.

The research community also shifts. And then there are the challenges of tracking people into adulthood as they disperse all over the country and get tired of us asking them questions every couple of years.

That reminds me of the 75-year Harvard study on happiness. Are there other ways to find firm scientific answers in a country dealing with more wildfire and smoke?

In European countries with socialized medicine and a national healthcare system, it becomes easier to examine a person’s history over a long period. If someone lives in Stockholm, Sweden, their whole lives and every medical encounter they’ve ever had are easier to access. Based on that, you can create longer studies. They’re always a bit crude because they may not involve asking questions or looking at biomarker measurements, but at least you can see when the person went to the doctor, their health concerns, and what kind of restrictions they had. We can see if they had a chronic disease and the age at which they got it. There are lots of interesting things you can do with that.

However, when it comes to wildfire smoke, the research is overwhelmingly focused on short-term health effects.

In other words, it’s smoky today; it was smoky yesterday. What does that mean for people going to urgent care today? It’s that short-term. That’s a majority of the research that’s been published.

As our society comes to terms with this idea of living with fire and that fire and smoke are just in the cards for us moving forward, I think those questions are going to become more interesting and more important to address

What about wildland firefighters who spend up to nine months going from fire to fire without breathing apparatus? They have anecdotally high rates of cancer and mental health issues.

They have very high exposure.

It’s different from fighting a house fire, where firefighters have substantial protective equipment. In the wildland fire setting, a scarf over your mouth is pretty much what you’re looking at.

There have been many studies done to quantify their exposure. People go out to the field with them, and they measure the particulate matter concentrations in smoke, biomarker concentrations, and urine.

Based on our biological understanding of what smoke and particulate matter do to people, we’re not surprised if cancer rates and other bad outcomes go up. As we adapt to this reality of living with fire, it’s important to recognize that these wildland firefighters are not people you call up just occasionally when a fire breaks out.

They work the majority of the year fighting fires, which is very significant exposure for that group compared to the same people in the 1980s and 90s. The exposure is extreme, and we need to take care of those people.

What about socioeconomic disparities when it comes to wildfire smoke? Are there any differences in resilience and vulnerability?

Some published papers show differences in socioeconomics due to exposure to wildfire smoke, with neighborhoods of lower socioeconomic status tending to be more likely to be impacted by smoke.

In my opinion, it’s just a little different from some of the other environmental justice issues that we think about when we think about pollution.

If you buy a home next to a bustling road, as opposed to back in the neighborhood, the house near the busy road will cost less, all things being equal. Consistent, obvious socioeconomic disparities in urban air pollution are related to property values and other factors.

If there’s a wildfire in California and the smoke blows into Reno 200 miles away, we all get it. And if we don’t get it, it’s either too high up in the air, or the wind just pushed it somewhere else.

Wildfire smoke is not quite the same thing as thinking about traffic pollution in our inner city or urban environments.

But aren’t these communities growing toward our forests and other wild places?

There is this issue of the wildland-urban interface, which is the boundary between the forest and where people live. And a lot of times, it’s nicer homes out there.

If you think about Lake Tahoe, people like to live out in the forest. Ideally, it’s up on a hill so you can see the lake. Many of those houses are very expensive and vulnerable to fires because they’re being built in the forest.

As we approach that interface, it becomes tricky for firefighters to create lines or barriers to prevent the fire from reaching the people’s homes because they live right out in the forest. So that’s a little bit different, too.

There are so many technological innovations that help deal with urban pollution and wildfire smoke, which we can access from our phones. Are there any unconventional or innovative approaches to mitigate health problems related to wildfire smoke?

For a couple of hundred dollars, you can buy fans with high-quality filters. You can put them in your bedroom, decreasing the concentration of particulate matter. They are rated for different square footage. But in my family —my wife, myself, and our two kids— we have three.

We need to put them in our bedrooms at night if there’s smoke, or if I’m working from home, I carry it downstairs and put it next to my desk. They really do help.

The filters are kind of expensive to replace, but they work well in terms of adapting to living with more fire smoke. HVAC systems also have that capability, and just changing the filters on your HVAC generally helps.

This is the reality in the western United States now. It’s impacting other parts of the US as well, such as Canadian fires.