Science Friday
Hosted by Flora Lichtman and Ira Flatow
Original podcast
How well do we understand the long-term health risks to firefighters? Plus, researchers across the country are breeding pest-resistant trees.
3,766 words · 7 speakers
Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
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I'm Flora Lixman, and you're listening to Science Friday. Today in the podcast, forests and fires. As pests and diseases take down trees across the country, resistant trees are sowing seeds of hope. But first, how well do we understand the risks of firefighting?
I think that if we're going to ask young women and men to do this extremely dangerous work, they have a right to know all of the risks, not just the immediate risks, but the long-term risks that they're facing.
Fighting fires is, of course, an inherently dangerous profession, but it's not just the immediate risks of going into burning buildings or dropping into a burning forest. There are also long-term health hazards that come with being exposed to smoke and chemicals and other toxic substances. The World Health Organization classifies the profession of firefighting as carcinogenic. So in 2018, the National Firefighter Registry for Cancer was created by Congress to help us understand those risks better. It's been in the news recently because with federal budget cuts, the registry went offline and then went back up this week. Here with me to discuss this and why it's important are my guests. Murphy Woodhouse is a
reporter who's been covering this story for the Mountain West News Bureau and Boise State Public Radio in Idaho. He's also a former wildland firefighter. Dr. Sarah Jenke, Director of the Center for Fire, Rescue and EMS Health Research at NDRI USA in Kansas. Welcome to you both to Science Friday.
Happy to be here.
Really, really happy to be here.
Sarah, let's zoom out for a second. I mean, how well understood is this link between cancer and firefighting?
So there's enough science to say with scientific certainty, we know firefighting is linked to the development of cancer. So it's a group one carcinogen. So that's good news. And about 80% of research that's been done on firefighter health has been done in the last 15 to 17 years. The downside is most of that research has been done on structural firefighters, primarily white male firefighters, because that's the easiest group that we've had to work with. And it's the largest group within the fire service. So there is great data there, but a lot of the data on the other groups, like we have the low hanging fruit on this. And now we really need to start looking at women in the fire service, wildland firefighters, volunteers, racial and ethnic minorities. So we know a lot, but more research
is needed.
Did 9/11 play a role in raising awareness about long-term health effects of firefighting?
Definitely. I really do think that that research formed the basis of, wow, there's really more we need to dig into here on cancer, on behavioral health, on looking at cardiovascular risks, injury, all those things.
Murphy, you've been reporting on the National Firefighter Registry for Cancer and this link between firefighting and cancer, but you also have a personal connection to this story.
Yeah, no, absolutely. I mean, I mean, it feels like a like another life at this point. But yeah, I did my my first fire season, 2006, a short summer while I was doing my undergraduate on an engine and then three full fire seasons, 2008 to 2010, on a type one hand crew based out of southeast Idaho. And, you know, a very distinct memory that I have from that time, especially towards the end of that time, is just experiencing the intense exposures to ash and dust and just all of the kind of crazy things that you come into close contact with in that line of work. And then after after the seasons, like going online
and and looking around, like, you know, what do we know? What information is is out there? And just really just finding almost nothing and just almost not believing that there wasn't information on that. And so, you know, when I got to the Mountain West News Bureau just over two years ago, my my first feature was on the NFR enrollment portal going online.
The National Firefighter Registry.
Thank you very much. Yeah, exactly. That. Yeah, the portal to register. So I did a story on that as well as just kind of the, you know, the larger issue of this this major gap in knowledge, especially with Wildland folks that that's a part of. And and during that reporting, I personally registered. So I am among roughly 24,000 folks who are in this this registry right now.
Sarah, why is this registry important?
Because there's so much that we don't know. And there's so much that we can't get from individual, smaller scale studies, even even large studies. So one of the big studies that everyone references in this area is the study that Doug Daniels did from NASH, 30,000 firefighters, Chicago, Philly, and San Francisco. Great data on that. It gave us more information than we ever had before, for large metropolitan departments. But does that generalize to the volunteer fire service? Does that generalize to other groups? In particular, with that study, there were only 991 women. So when you look at the estimates of risk for several of these cancers, given that they're relatively rare, particularly while you're on the job and and young.
It's hard to to look at that. So we really have to have, you know, the conversation around promoting this and and bringing this before Congress. And it did. The beautiful part about it is that every fire service organization signed on to support this effort.
Wow.
And everyone worked together. It was it was really this amazing collaborative approach. And it was a heavy lift to get it passed. But on the science side, we had to make the argument that this is the type of registry that we need, because otherwise, we don't know. For firefighters, you know, the the challenge of it is that for firefighters on on health records, whether it's your cancer registry or your death certificate, if your occupation is recorded, if you're not an active firefighter, it says retired. If you're a volunteer firefighter, it says whatever your primary job is. Like, Murphy talked about being a wildland firefighter. If he died or got cancer today, and it was on a record, he'd be listed as a reporter. So we didn't have and don't have a broader understanding
of the impact for the fire service. We don't track most retired firefighters. So really, there's there's no other way to get this information, to really look in both for the how does this impact policy? How does this impact legislation, presumptive cancers? And also on the intervention and prevention side. We don't know who's at highest risk. So we don't have that information to say which screenings should we be doing for which people and and really like honing in prevention and intervention.
Is that the ultimate goal, is sort of understanding this at a granular level? So you can do intervention and prevention?
Yes, yes. And to understand, you know, the big picture, but also like signing on for the registry, and I'm sure Murphy was annoyed at all the questions that were asked. I can tell you, we appreciate every single question that you answered, because it does go into detail about where you've worked, what exposures you had, what PPE, what protective equipment you did have at the time, how that's changed across time. You know, a lot of that information, we just don't have. I was on the subcommittee that helped form the questionnaire, which is why I'm personally apologizing to Murphy and any other firefighters listening.
I wasn't annoyed, but I will say that I did struggle with the questions, for sure.
Yes, yes. It's it's a lot, but it is the level of information that we need to get. Because we, like I said, we know a lot about some groups, and then there's some that I think we might be underestimating risk for.
Murphy, what's the latest with this registry? I know it was offline since the beginning of April. Where does it stand now?
Yeah, so the online enrollment portal, I mean, the very same one that I used a couple of years ago to enroll myself, you know, I've been regularly refreshing that page since early April when it went offline. And just today, just this very afternoon, the page opened. I certainly cannot speak to, you know, its level of functionality right now. And I'm certainly not going to go through the full registration process again. But for right now, I am, I am getting a real live webpage and had not been was getting a handful of errors for the past month and a half. So it does seem that a lot of the NFR team could be coming back and could be coming back fairly soon. That certainly
does seem to be a move in the direction of the NFR being functional again.
I feel like we're at step one, building this back up. But now we have a few hundred steps to go within the fire service to get it all, you know, back up and running. And contracts were finally in place. We're at 24,000 ish firefighters. Our goal at minimum is 100,000. And it's really been the team in the field, meeting with firefighters, going to meetings, building the trust. So I'm optimistic, but I think we're going to be a slow rebuild to get back to where we were.
And I do just want to jump in there super quick because I mean, it's, you know, in the last several months, and I'm literally looking at the dashboard of enrollees right now. Last several months, I've seen some of the highest rates of enrolling. My understanding of it was something on the order of 1,600 new enrollees every single month. And so this thing has been down for nearly a month and a half. I mean, we're literally talking about hundreds and hundreds of people who may have otherwise been able to enroll. So I mean, it, this shutdown came at a time when it really felt like there was a great deal of momentum. Even with it back online, all of Sarah's concerns regarding the sort of trust building that was necessary to get to this point are still very much the case. And so like, it just being back online, I mean, that doesn't, that doesn't mean like
it's just going to go right back to 1,600 a month necessarily.
You know, Sarah, is cancer the top concern? Are there other health risks that you're interested in studying?
So cancer is definitely one of the concerns, but I don't think it's the only one. And I also think that it's so interrelated with all the other health issues that we see in firefighters. So when we try to do comparisons of, you know, e- even how many firefighters have cancer in this country, we don't have that data. The NFR should hopefully be able to give us that. We know that IFF puts more, that, which is the union, National Union for Firefighters, puts more deaths from cancer on their memorial wall than any other cause every year. But we do know that on duty, you're more likely to experience a heart attack on duty or a cardiac death. We also know that your department, fire department, is more likely to experience a suicide than they are a on-duty death.
So it's, it's pretty complex. But also, mental health, we know that chronic occupational exposures to stress lead to epigenetic changes, which lead to inflammation, which likely are leading some of the causes on the cardiovascular disease and the cancer. It's a pretty complex, I mean, it's, it's why it's an interesting group to work with. You know, circadian rhythm from shift work is a topic that we're, we've got a lot of focus on right now. There's never a lack of research questions in this population.
Murphy, this must all feel really close to home for you. What do you want to leave our listeners with?
Yeah, no, I really do appreciate this question. And like, you know, it is, it is kind of strange, you know, when you're reporting on something that is, something that you have real, personal connections to. I still have a lot of friends doing this work. And, you know, you know, my, my basic feeling is that wild and fire, a- and certainly fire in general, just the day-to-day is, is plenty dangerous. You know, I personally have had several close calls that could have gone very, very differently for me. And that's to say nothing of, you know, our growing knowledge about the very real long-term risks here. I think that if we're going to ask young women and men to do this extremely dangerous work, they have a right to know all of the risks, not just the immediate risks, but the
long-term risks that they're facing. And the NFR, by all accounts, everyone that I've spoken to who is expert on, on what it is and its potential, the best existing tool to really give these people, these, these, these public servants, information that they have a right to. These are answers that we all need, as uncomfortable as I think these answers will ultimately be.
I think that's the perfect place to leave it. Thank you both for coming on the show today.
Thank you. I really appreciate the interest in this.
Murphy Woodhouse is a reporter for the Mountain West News Bureau and Boise State Public Radio in Idaho and is a former wildland firefighter. Dr. Sarah Jenke is the director of the Center for Fire, Rescue, and EMS Health Research at NDRI USA in Kansas.
We have to take a quick break, but don't go away. Coming up, some hope in the fight against tree diseases.
A pest-resistant elm is already a thing you can buy.
Really?
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Billions of American trees have died across American forests because of invasive pests and pathogens. Out east, our forests look different than they used to, as ash and elm and hemlock and beech trees dwindle. But sometimes, in those decimated groves, scientists find a seed of hope, a lone tree that is somehow resistant to whatever felled its neighbors. My next guest is part of a national effort to locate these pest-resistant trees and use them to make future forests stronger. Lee Greenwood is the Forest Pest and Pathogen Program Director at the Nature Conservancy. She's based in Missoula, Montana. Welcome to Science Friday.
Thanks so much for having me, Flora.
Okay, tell me about the search for pest-resistant trees. Like, how do you look for them, and what is it like when you find them?
What's really cool is anybody who loves trees, who's interested in forests and goes for hikes, or enjoys the outdoors, can go look for these trees. If you find a tree that looks a lot better than its neighbors, and it's a type of tree that's being attacked broadly by pests and pathogens, that might be the one. So we not only have scientists looking for them, but we have everyone else looking for them, so that we can find as many of these lingering trees as possible.
What is a lingering tree?
So really, what we are talking about is trees that have some kind of quality within themselves that needs to be inherited from parent tree to seed tree, that gives it a chance that the other neighboring trees don't have to resist the pests and pathogens that attack it. And sometimes, that's temporary, so the tree only lives, let's just say, five years longer. And then other times it's very resilient. And so that means the tree lives out its natural lifespan. And both of those things are worthwhile to look for. And that's why it's so tricky to find what we call lingering trees.
Do we understand what makes these pest resistant trees resistant?
The answer is that it's different for every tree. And we don't actually need to know exactly how they do it. As long as we know that they can hand it down through the generations through their genetics.
Once you find a pest resistant tree, what happens? What happens next?
Well, we need to bring it into our collections of pest resistant trees through samples of the leaves, through scientists knowing where it is and establishing that it's, you know, owned by an entity willing to share it.
In terms of if it's on private land, for instance. And then if things are going well, we can raise small saplings and then test them by using very practical tests, like actually literally putting bug eggs on them and then seeing if those eggs mature into larvae that can become adults or if they don't.
What scale of impact could this have? Finding and then breeding these pest resistant trees?
We are looking for the biggest possible impact that the imagination has. We want to create resistant trees that can be used to reforest these threatened species across their entire natural range. Over a very long time span, it's an incredibly ambitious project.
When will I be able to go to my garden center and get a pest resistant beech, for example?
Oh, well, a pest resistant beech is a really long ways off. But a pest resistant elm is already a thing you can buy.
Each type of tree is on its own pest and pathogen journey. And some of those journeys have been shorter and simpler and started earlier. So some forest pests are older than others and when they entered the United States or Canada. So we already have some pest and pathogen resistant elms. And we already have some pest and pathogen resilient pines.
If someone listening thinks that they know of a pest resistant tree that's doing a little better than the trees nearby, outliving them, what should they do?
We would love it if you could use the app that we work with, which is called TreeSnap, and download TreeSnap and put an entry into TreeSnap about your tree. You take some pictures, you fill out a really manageable little questionnaire about your tree, and then you send it in. We make sure all that information gets to the right scientists in the right way, so they can determine if that tree could be part of our big project.
Thank you, Lee.
Lee Greenwood is the Forest Pest and Pathogen Program Director at the Nature Conservancy, and she's based in Missoula, Montana. And if you want to learn more about this topic, you're in luck. Go to sciencefriday.com/trees to read a story by reporter Sophie Hartley.
And that is about all we have time for. Lots of folks helped to make this show happen, including Diana Plasker, Jordan Smudgick, Emma Gomez, Valesa Mayers. I'm Flora Lichtman. Thanks for listening.
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