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Tag: firefighter health

A fire supervisor asks, “Why didn’t I see this coming?”

Author BillPosted on Categories UncategorizedTags , , 6 Comments on A fire supervisor asks, “Why didn’t I see this coming?”

Fire personnel and mental health issues

Eclipse Complex firefighters
Firefighters on the Eclipse Complex of fires, Klamath NF, 2017. Photo by B. Patton. InciWeb.

From Bill: I have been communicating for a few weeks with a U.S. Forest Service Forestry Technician about an article they wanted to submit about helping employees who are struggling with mental health issues. The text arrived by email yesterday:

Sorry for the delay. I’ve actually been really busy at work, and then I had an employee resign for mental health reasons today.  For that reason I don’t want to put this off anymore.

Here is the article. The author wished to remain anonymous.

It has now been over a year since the start of the 2020 fire season.  It has also been just over a year since the COVID-19 pandemic truly began affecting my life, and the lives of the people I work with.  A year ago I was onboarding my crew in full COVID PPE, issuing gear and sending them home to telework while we figured out how to fight fire during a pandemic.  I was legitimately thrilled to start the 2021 season, thinking the pandemic and the stress was behind us and that finally we could get back to ‘normal’.

But today I had a talk with one of my employees about their incredibly difficult off-season and the mental health struggles they’ve been dealing with.  The details of their struggle aren’t critical here.  It could be about money, family, a relationship, personal health, or simply happiness and life satisfaction.  What is important is that since the end of the 2020 fire season, almost half of the employees I supervise have approached me with mental health concerns just like these.  Yes, you read that right.  Nearly half of my employees are struggling to cope to the extent that they approached me needing help and advice.  And while I was aware, as I’m sure you are, that the pandemic has caused trauma, stress, depression, and self harm at unprecedented levels potentially not seen before, it hadn’t personally affected me until now.  And now it’s here, and not in a small way.  This is not an anomaly. This is a trend.

At first I had a serious bout of self reflection and introspection.  “What have I done to these people that they’re hurting so badly?”  “What happened last season to push them in this direction?”  “Did I drive them too hard?”  “Why didn’t I see this coming?”  I consulted with some of my mentors and realized that no, it isn’t necessarily me.  It’s us.  It’s our culture.  We think we can handle just about anything.  We regularly and voluntarily place ourselves into environments that define the word stress, and we do so with big dirty grins on our faces.  And as the season grinds on we find a few ways to cope, and they’re usually extremely unhealthy.  It should not surprise us that this approach is bound to break down.  But one thing we don’t do is talk about how we’re feeling.  We grind it out because we know winter is coming.  And we think that will help.  But what if it doesn’t?  I’m writing today to say that it doesn’t.  Winter unemployment wasn’t a holiday.  Fire season was a holiday from reality.  And when work ends, the harsh reality of “real life” is waiting there staring you in the face.  And now we are returning to work not refreshed and fit and ready to go, but drained from a stressful winter.  And if this problem exists where I work, I truly believe it must be happening where you work, whether it’s being talked about or not.

So here’s my advice.  I’m not a mental health professional so take it for what it’s worth.  I’m just a guy who’s done this for a little while.

Firefighters – know that you are not alone.  Literally everyone experiences the same anxiety and struggles just like you do, in different ways and at different times.  The past 12 months have been brutal.  Everyone on my crew broke their career overtime records in 2020, and did so while it felt like the world was imploding around us, and while we were isolated from friends and family.  Stress on top of stress for 6-8 months followed by being set adrift and alone into the world once the snow flies is mentally taxing in a normal year.  Doing all of that during a pandemic was bound to push people over the edge.  I only ask that you realize that we are here for you.  Your supervisors.  Your coworkers.  Even the random people you meet for one shift on a fire and never see again.  We’re here for you because we are you.  We experience it too.  And while we may not have all the answers, we’re all better off seeking them together.  Speak up.  Your voice will empower the voices of others.  And there are free and anonymous resources to connect you with professionals regardless of which agency you work for. Talking about it will help.

Supervisors – Make yourself available and approachable.  I am as guilty as the rest of you.  In our line of work, I am a stereotypical fireline supervisor.  I am loud and outspoken, and I portray a confidence that I’m sure tells my subordinates that I am more or less bulletproof and immune from these issues personally.  That is not helpful.  That does not give your people the confidence to speak up.  Show humility.  Lose the ego.  Let them see your weaknesses.  Empower your employees with the knowledge they need to get help.  Give them contact information for the Employee Assistance Program (EAP).  While I am at times a major skeptic when it comes to believing “the agency” has our back, I can say for certain that my agency’s EAP has done incredible work for the people I’ve put in touch with it.  And even if no one has approached you for help, you can still foster an environment that encourages open communication and the ability to come to you with issues.  The egomaniacal “shut up and dig” approach may work in some cases, but this is not one of them.

Thanks for indulging me in my brief but passionate soapbox rant.  I don’t claim to have the answers.  I have no formal training in mental health or therapy.  But I’ve done this job for a long time, and I’m seeing looks on faces I’ve never seen before.  We’ve been getting better recently about talking.  Opening up.  Discussing as opposed to directing.  But I believe we still have work to do if we’re going to create a culture and a family that feels comfortable speaking up and opening up about mental health.  Life is stressful enough these days.  Doing what we do on top of all of that is bound to be just a little too much sometimes.  Drop the ego and be a human.  A little empathy goes a long way.  Have a safe season.

 

Note from Bill:

Suicide rates among wildland firefighters have been described as “astronomical.

Help is available for those feeling really depressed or suicidal.

Mass Bird Die-Off Linked to Wildfires and Toxic Gases

Author BillPosted on Categories UncategorizedTags , , 3 Comments on Mass Bird Die-Off Linked to Wildfires and Toxic Gases

Using observations from crowdsourced science and weather location data, researchers concluded that wildfires caused a mass die-off of birds in the western and central United States in 2020.

By Joshua Rapp Learn

After an abnormally large number of migratory birds turned up dead in people’s backyards in Colorado and other parts of western and central U.S. states, locals began to document their observations on a crowdsourced science platform called iNaturalist. Within the app, a special project was set up specifically for this die-off, which occurred in August and September 2020, so that records of the dead birds could be compiled together.

Around the same period as the birds’ deaths, more than 3 million hectares (7.8 million acres) of land burned, which resulted in habitat loss and the emission of toxic compounds that threaten the health of both avian species and humans. In addition, snowstorms struck parts of the Northwest in early September while these birds were in the midst of their annual migration. Some areas experienced temperature drops of as much as 40°C (72°F) in just a few hours.

Mountain Bluebird, male
Mountain Bluebird, male. Photo by Bill Gabbert.

Researchers heard of this die-off event and wanted to see whether there was a link between the birds’ deaths and the other major events (wildfires and snowstorms) occurring in the United States at the time. In a new study published in GeoHealth, Yang et al. used the iNaturalist data, which included recordings of a number of migratory species such as warblers, geese, hummingbirds, swallows, flycatchers, and sparrows. The scientists also studied map readings that showed where observations were taken on iNaturalist to compare the locations of the birds’ deaths with the locations of the wildfires and storms.

Their findings were starkly clear. “The wildfire and also the toxic air were the two factors that influenced the birds’ mortality,” said Anni Yang, a postdoctoral fellow in spatial ecology at Colorado State University and one of the study’s authors. There was a strong correlation between the observations of dead birds and wildfires and the toxic gases they produced, but not with the early winter storms.

“The birds are sensitive to the environment,” Yang said. The respiratory system of avian species in particular easily can be damaged by air pollution. Although wildfires have always occurred and birds have evolved to cope with them in some measure, the combination of climate change and decades of fire suppression in parts of the United States has led to fires that burn far hotter and larger than fires that burned in centuries past. The larger fires could cause problems that birds nowadays aren’t capable of dealing with.The researchers also discovered that there were some differences in local areas. In parts of California, for example, more bird deaths occurred farther from the wildfires. The reason could be secondary impacts of the fires affecting humidity levels, which could lead to the deaths of birds in hot, humid air over the ocean.The researchers also noticed other trends. Land cover had an impact on bird deaths; the data showed that more birds died in urban areas. According to the authors, the reason could be known issues that affect birds, such as building strikes. But Yang noted that this correlation may be slightly biased because of quarantining due to the pandemic. In other words, people were spending more time in urban areas and perhaps paying more attention to dead birds around their homes, which inadvertently may have boosted the numbers in cities compared with rural areas.Yang also suggested that the lack of correlation between bird deaths and the snowstorms could be explained by shortcomings in the crowdsourced science application. In that case, fewer people may have been going outside during the bad weather, which could translate to fewer observations of dead birds.

Yang said other local factors might have played roles in the deaths of some species. The researchers looked at all bird deaths equally, but different species could be affected in different ways by climate events like wildfire smoke or a snowstorm.

Rongting Xu, an ecosystem modeler at Oregon State University and another of the paper’s authors, said that it would be great to run the same study over multiple years, comparing the summer of 2020 with previous summers, for example, to see whether wildfires or early snowstorms in other years caused similar die-offs. Such long-term examinations could also reveal whether factors like climate change are playing a role in bird deaths, she said. (GeoHealth, https://doi.org/10.1029/2021GH000395, 2021)

—Joshua Rapp Learn (@JoshuaLearn1), Science Writer

This article first appeared at EOS, Science News by AGU.
Citation: Learn, J. R. (2021), Mass bird die-off linked to wildfires and toxic gases, Eos, 102, https://doi.org/10.1029/2021EO156447. Published on 26 March 2021.

 

NPR: Firefighters are facing a growing mental health challenge

Author Bill GabbertPosted on Categories UncategorizedTags 22 Comments on NPR: Firefighters are facing a growing mental health challenge

Interviews with several firefighters. One said, “Things we did 10 years ago are no longer working”

Smoke column from the Williams Fork Fire in Colorado
Smoke column from the Williams Fork Fire in Colorado Aug. 15, 2020. USFS photo.

National Public Radio has an interesting interview with several firefighters, and a researcher who studies issues that affect firefighters. Check it out — it’s only seven minutes.

And speaking of firefighters’ health, you need to read the story of one who has survived two fire shelter deployments. He describes some of the challenges he’s dealing with.

Wildfire smoke carries microbes that can cause infectious diseases

Author Bill GabbertPosted on Categories UncategorizedTags , 3 Comments on Wildfire smoke carries microbes that can cause infectious diseases
Calwood Fire, Oct. 17, 2020
Calwood Fire, Oct. 17, 2020. Photo by Ben Nelson, Envision Studio, Boulder, Colorado.

Wildfire smoke contains microbes, a fact that’s often ignored, but one that may have important health repercussions.

In 2008, Captain Matthew P. Moore, a firefighter with the Murrieta, California Fire Department, died after being infected with a rare brain-eating amoeba that usually lives in soil. A biopsy showed his brain had been invaded by the parasite Balamuthia mandrillaris which enters the body through the lower respiratory tract or through open wounds. It is believed Captain Moore inhaled the parasite while fighting wildfires.

In an article published December 18 in Science, Leda Kobziar and George Thompson called the attention of the scientific community to the health impacts of wildfire smoke’s microbial content.

Smoky skies caused by wildland fires are becoming seasonal norms, especially in some parts of the United States and Australia. In 2020, wildfires in the Western U.S. set new records and led to extremely unhealthy or hazardous air quality levels for many weeks in a row.

It’s well-documented that exposure to wildfire smoke can damage the heart and lungs. Respiratory allergic and inflammatory diseases, including asthma and bronchitis, are also worsened by smoke exposure.

“The health impact of inhaling wildfire smoke increases dramatically during high-emissions wildfires and with long exposure,” said Kobziar, associate professor of Wildland Fire Science at the University of Idaho. “Yet, the risk of infection to the respiratory tract after this exposure is frequently overlooked.”

What role do microbes in wildfire smoke play in the spread of disease?

Wildland fire is a source for bioaerosol, airborne particles made of fungal and bacterial cells and their metabolic byproducts. Once suspended in the air, particles smaller than 5 μm can travel hundreds or even thousands of miles. Their movement depends on the fire behavior and the atmospheric conditions.

microbial cell transport wildland fire
A simulation of microbial cell transport potential using measured smoke cell concentration, particulate matter, and fuel consumption values shows a snapshot of the number of microbial cells under 2.5 mm in aerodynamic diameter per kilogram of air downwind of a fire in Utah’s Fishlake National Forest, USA. Leda N. Kobziar and George R. Thompson III.

Bacteria and fungi can be transported in these wildland fire smoke emissions. The consequences for more immediate populations, such as firefighters on the front line who often spend up to 14 consecutive days in smoky conditions, are likely greater given that microbial concentration in smoke is higher near the source of a fire. For example, the U.S. Centers for Disease Control and Prevention counts firefighting as an at-risk profession for coccidioidomycosis, an infection caused by a pathogenic fungus well known to be aerosolized when soils are disturbed.

“We don’t know how far and which microbes are carried in smoke,” said Thompson, associate professor of Clinical Medicine at UC Davis. “Some microbes in the soil appear to be tolerant of, and even thrive under, high temperatures following wildfires.”

As Kobziar explained, “At the scale of a microbe, fire behavior research has shown that heat flux is highly variable, so it may be that many microbes aren’t even subjected to the high temperatures for very long. They may also be protected in small clusters of particulate matter.”

The potential for wildland fire’s microbial content to affect humans who breathe in smoke, especially from high-emissions wildfires or for multiple weeks, is appreciable. How far and which microbes are transported in smoke under various conditions are critical unknowns, but the relevance of these questions is increasing with longer wildfire seasons and higher severity trends.

Study found hazardous air quality conditions at fire camps in Oregon and California

Author Bill GabbertPosted on Categories UncategorizedTags , , , , , , , , , 13 Comments on Study found hazardous air quality conditions at fire camps in Oregon and California

Smoke exposure levels at the Creek Fire ranged from hazardous to unhealthy for 30 days

(From Bill: Wildland firefighters and people who live in areas where long-term fires are common, such as Northern California and the Northwest, know that smoke can persist for days or weeks and can cause or aggravate respiratory and other medical issues. But knowing it exists and having peer reviewed quantifiable data proving it is hazardous to health, are two different things. Science like this could lead to changes that may benefit firefighters and the general public.)

In September and October the Centers for Disease Control and Prevention (CDC) deployed two staff members to serve as air resource advisors at wildfires in Oregon and California.

Air resource advisors were fully integrated into the wildfire incident management teams to provide insights into understanding and predicting smoke exposure levels. The individuals interacted with stakeholders, including air quality regulators, fire personnel, public health practitioners, and community residents. A primary aspect of this engagement was to forecast smoke levels for areas immediately affected by fires and generate a daily smoke outlook to keep stakeholders informed about prevailing smoke levels. 2020 is the first year during which the CDC worked with the Interagency Wildland Fire Air Quality Response Program and deployed staff members as air resource advisors for wildfire incidents.

From August 31 to September 14, 2020, one CDC staff member supported wildfires in central Oregon’s Cascade Range east of Sisters, which included the Beachie Creek, Holiday Farm, Lionshead, and Riverside fires. Strong east winds across the Cascade Mountains resulted in more than 560,000 acres of fire growth from September 7 through 10.

satellite photo fires smoke Washington, Oregon, and California
GOES-17 photo of smoke from wildfires in Washington, Oregon, and California at 5:56 p.m. PDT Sept. 8, 2020. The photo was taken during a very strong wind event.

Another CDC staff member was deployed to the Creek Fire from September 20 to October 5, 2020. This fire near North Fork, California started September 4 and grew to 193,000 acres during its first week; as of December 3, 2020, the fire had burned 379,895 acres.

Air quality study, fire camps, 2020
Abbreviation: PM2.5 = particles with aerodynamic diameters ≤2.5 μm.
       * Sensitive groups include persons aged ≤18 years; adults aged ≥65 years; pregnant women; persons with chronic health conditions such as heart or lung disease, including asthma and diabetes; outdoor workers; persons experiencing homelessness, and those with limited access to medical care. (https://www.cdc.gov/air/wildfire-smoke/default.htm).
       † Fire camps typically offer logistical support to the wildfire suppression operation by providing firefighters and incident personnel sleeping locations (camping), morning and evening meals, workspaces, and administrative services.
       § The monitoring instrument in North Fork, California, recorded errors and did not report data during September 12–15, 2020.
       ¶ Start date of Creek Fire in California was September 4. Start dates of fires in Oregon were as follows. Lionshead was August 16; Beachie Creek was August 16; Holiday Farm was September 7; Riverside was September 8.

During these two deployments, several public health concerns came to light. Of note, although smoke from wildfires drifted long distances and affected downwind communities, the brunt of poor air quality was observed in communities adjacent to wildfire incidents. For example, communities near the fires in California and Oregon experienced high concentrations of PM2.5, as measured by air quality monitors, resulting in “Unhealthy” to “Hazardous” conditions, as defined by the U.S. Environmental Protection Agency Air Quality Index.

Fire personnel who camped and rested between work shifts at nearby fire camps (North Fork, California and Sisters, Oregon) were also exposed to poor air quality levels. These fire camp exposures contribute to higher overall cumulative smoke exposure and, along with other occupational risk factors such as fatigue and stress, could limit recovery that is much needed for fire personnel while away from the active fire perimeter. In addition, environmental hazards such as extreme heat and higher concentrations of ambient carbon monoxide were prevalent during days with heavy smoke and after extreme fire growth days. These hazards added a layer of complexity to fire response efforts and might have limited fire personnel recovery between work shifts.

From: Navarro K, Vaidyanathan A.  — Notes from the Field: Understanding Smoke Exposure in Communities and Fire Camps Affected by Wildfires— California and Oregon, 2020. MMWR Morb Mortal Wkly Rep 2020;69:1873–1875. DOI: http://dx.doi.org/10.15585/mmwr.mm6949a4

Thanks and a tip of the hat go out to Bob.

Smoke — and the health of firefighters

Author Bill GabbertPosted on Categories UncategorizedTags , , 10 Comments on Smoke — and the health of firefighters
smoke pyrocumulus bushfires Australia
Photo of smoke from bushfires by Merrin Macleod on a flight from Canberra to Melbourne, Australia, posted January 4, 2020.

Originally published by the Centers for Disease Control and Prevention

While research has not yet been conducted on all the hazards and risks associated with the wildland firefighting job, the National Institute for Occupational Safety and Health (NIOSH) is asked numerous questions about the hazards of fighting wildland fires. This blog is designed to answer some of those questions.

What Is in Wildland Fire Smoke?

Wildland fire smoke is a mixture of gases and particles such as carbon monoxide (CO) and respirable particulate matter (PM) that may cause short- and long-term health effects. Wildland firefighters can be exposed to smoke at wildfires and “prescribed” fires (planned and intentionally ignited low-intensity fires). The contents of and exposure to wildfire smoke can vary greatly throughout the day depending on the vegetation type, fire behavior, and meteorological conditions. Research has shown that wildland firefighters have been exposed to gases and particles such as CO and PM above the occupational exposure limits during both wildland and prescribed fires. While burning vegetation is the primary exposure of concern for wildland and prescribed fires, when fires burn in the wildland urban interface (WUI, where wildland vegetation and urban areas meet) the smoke may contain compounds that are more similar to what structural firefighters encounter. Wildland firefighters will often suppress these fires and may be exposed to some of the hazardous compounds of WUI smoke such as volatile organic compounds (VOCs), flame retardants, and polycyclic aromatic hydrocarbons (PAHs). However, wildland firefighters do not have the benefit of wearing some of the personal protective equipment (PPE) typically used in a structural response (e.g., self-contained breathing apparatus [SCBA], turnout gear) that could provide protection from these compounds. Additionally, wildland firefighters may be exposed to smoke at firefighting base camps (incident command posts) where they eat and rest while off-duty.

What Do We Know About the Health of Wildland Firefighters?

Cardiovascular and Lung Health

In the past decade, several studies have linked exposure to wildfire smoke to short-term health effects, such as increases in inflammation and respiratory effects, for example, lung function decline.[i] However, these studies have only examined the health effects across a few shifts or a single fire season. It is not clear if these adverse health effects continue after fire season and whether they worsen after several seasons of fighting fires. Researchers suspect that exposure to particulate matter and other contaminants from wildfire smoke, heavy physical exertion, existing health and behavior risk factors, and cardiovascular strain could contribute to sudden cardiac events for wildland firefighters. Recent research indicated that wildland firefighters may be at an increased risk of mortality from cardiovascular disease and lung cancer than the general public from career exposure to wildfire smoke.[ii]

COVID-19

The strenuous work, long work shifts, close living and working conditions, limited access to hygiene supplies, and a workforce that responds to incidents all over the country on short notice to wildland fire incidents may be conducive for the transmission of infectious diseases, including SARS-CoV-2. Exposure to air pollutants in wildfire smoke can irritate the lungs, cause inflammation, alter immune function, and increase susceptibility to respiratory infections, possibly including COVID-19.[iii] In addition to potentially making firefighters more vulnerable to getting COVID-19, inflammation in the respiratory tract due to wildfire smoke might also increase the risk of developing more severe outcomes for those with COVID-19.[iv] Wildland firefighters should implement the recommendations described in the CDC’s FAQ for Wildland Firefighters to prevent infection and spread of COVID-19.

Heat-Related Illness and Rhabdomyolysis

Due to the nature of their work, firefighters are at risk of developing severe heat-related illness (such as heat stroke) and rhabdomyolysis (muscle breakdown).[v],[vi] Delays in diagnosis and initiating treatment of these illnesses increase the risk of permanent muscle damage. Since 2010, 62 cases of severe rhabdomyolysis among wildland firefighters have been reported to a passive surveillance system designed to capture fatalities and certain types of injuries and illnesses including rhabdomyolysis. The actual number of cases is likely higher due to underreporting and inconsistencies in reporting requirements and systems. Prior to 2010, no cases were reported.

Hearing

Wildland firefighters work around power tools and heavy equipment that produce noise levels that are hazardous to hearing. In addition to hearing loss, noise exposure may also cause tinnitus (ringing/buzzing in ears), increased heart rate, fatigue, and interfere with verbal communication. Researchers from NIOSH and the United States Forest Service (USFS) evaluated personal noise measurements on 156 wildland firefighters conducting various training and fire suppression tasks, and reported that 85 of the 174 measurements were above the NIOSH maximum allowable daily dose[vii]. A follow-up study showed use of hearing protection was mixed; while almost all the wildland firefighters were aware of the noise in their environment and potential risk, very few were enrolled in hearing conservation programs.

What Are NIOSH Researchers Doing to Better Understand Exposures and Health Effects?

NIOSH is currently conducting research to understand the exposures and health effects of firefighters suppressing wildland and WUI fires. NIOSH researchers and collaborators at the US Forest Service and Department of the Interior have finished the second year of a multi-year study investigating exposures and health effects among six federal 20-person firefighting crews. The primary goal of this study is to measure exposures in the wildland fire environment and examine associations between those exposures and changes in lung, cardiac, kidney, and hearing function during each fire season and the off season over multiple fire seasons. This study has been paused in 2020 due to COVID-19 but is expected to resume.

To understand exposures and health effects faced by WUI firefighters, NIOSH is working with researchers from the University of Arizona and University of Miami to expand an existing collaborative research study (the Fire Fighter Cancer Cohort Study) to collect data regarding exposures from WUI fire incidents during the 2019 and 2020 fire seasons. Characterizing the types of chemicals, as well as the routes and levels of exposures, will help us understand health risks for wildland firefighters.

NIOSH is also in the process of developing a study assessing self-reported exposures to wildfire smoke and COVID-19 health outcomes among wildland firefighters. Additional information about this research will be available soon on the NIOSH Fighting Wildfires Page.

 

Authors of this article:

LCDR Corey Butler,MS REHS, is a Lieutenant Commander with the United States Public Health Service and an Occupational Safety and Health Specialist in the NIOSH Western States Division.

CAPT Christa Hale,DVM, MPH, DACVPM (Epi), is a Captain with the United States Public Health Service and Senior Epidemiologist and Veterinarian in the NIOSH Western States Division.

Kathleen Navarro, PhD, MPH is an Associate Service Fellow with the Division of Field Studies and Engineering.

Elizabeth Dalsey, M.A., is a Health Communication Specialist in the Western States Division.

CAPT Chucri (Chuck) A. Kardous, MS, PE, is a Captain with the United States Public Health Service and a research engineer with the NIOSH Division of Field Studies and Engineering.

Pamela S. Graydon, MS, COHC, is an Electronics Engineer working in hearing loss prevention in the NIOSH Division of Field Studies and Engineering. 

CAPT David C. Byrne, Ph.D., CCC-A, is a Captain with the United States Public Health Service and a research audiologist with the NIOSH Division of Field Studies and Engineering.

References

[i] Adetona O, Reinhard T, Domitrovich J, Boryles G, Adetona A, Kleinman M, Ottma R, Naher L [2016]. Review of the health effects of wildland fire smoke on wildland firefighters and the public. lnhal Toxicol 28(3): 95-139. Available from: https://pubmed.ncbi.nlm.nih.gov/26915822/

[ii] Navarro K, Kleinman M, Mackay C, Reinhardt T, Balmes J, Broyles G, Ottmar R, Naher L, Domitrovich J [2019]. Wildland firefighter smoke exposure and risk of lung cancer and cardiovascular disease mortality. Environ Res 173:462-468. Available from:https://www.sciencedirect.com/science/article/pii/S001393511930194X

[iii] Reid CE, Maestas MM. Wildfire smoke exposure under climate change: impact on respiratory health of affected communities. Curr Opin Pulm Med 2019;25:179–187.

[iv] Moore JB, June CH. Cytokine release syndrome in severe COVID-19. Science 2020;368:473.

[v] West MR, Costello S, Sol JA, Domitrovich JW [2020]. Risk for heat-related illness among wildland firefighters: job tasks and core body temperature change. Occup Environ Med77(7):433-438. Available from: https://pubmed.ncbi.nlm.nih.gov/31996475/

[vi] NIOSH [2012]. Report of a NIOSH health hazard evaluation, HHE 2011–0035. By Eisenberg J and McFadden J. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. Unpublished.

[vii] Broyles G, Butler C, Kardous C [2017]. Noise exposure among federal wildland fire fighters. J Acoust Soc Am 141(2) EL177. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5975217/