🚒 Rising Alarms: Elevated ALS Risk in US Firefighters

Firefighters, the brave individuals who rush into burning buildings to save lives, face unique occupational hazards that extend far beyond the immediate dangers of flames and smoke. Recent attention has turned to a sobering connection between their profession and amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disease. Emerging research suggests that US firefighters may have up to twice the risk of developing ALS compared to the general population. This statistic has sparked urgent investigations, culminating in a groundbreaking national study launched in early 2026.

ALS, often called Lou Gehrig's disease after the famous baseball player who battled it, progressively destroys the nerve cells responsible for controlling voluntary muscles. Everyday tasks like walking, speaking, and eventually breathing become impossible as the disease advances. With no cure and an average survival of two to five years post-diagnosis, understanding why certain groups like firefighters are disproportionately affected is critical for prevention, early detection, and support.

The push for answers gained momentum through collaborations between firefighting unions, ALS research organizations, and patient advocacy groups. This concern is not abstract; it affects real families and departments across the country, prompting calls for better protective gear, long-term health monitoring, and recognition of ALS as an occupational illness in more states.

Understanding Amyotrophic Lateral Sclerosis (ALS)

To grasp the significance of the firefighter-ALS link, it's essential to understand ALS itself. Amyotrophic lateral sclerosis (ALS) is a rare but fatal neurological disorder that targets motor neurons—the specialized cells in the brain and spinal cord that send messages to muscles. When these neurons degenerate and die, muscles weaken, twitch, and atrophy, leading to paralysis.

About 90 percent of cases are sporadic, meaning they occur without a clear family history, while familial ALS accounts for the remaining 10 percent, often linked to specific genetic mutations like those in the SOD1 or C9orf72 genes. Symptoms typically begin subtly, such as muscle cramps, slurred speech, or dropping objects, before escalating rapidly. Diagnosis involves clinical exams, electromyography (EMG) to detect nerve-muscle communication issues, and ruling out mimics like multiple sclerosis.

In the US, around 5,000 new cases are diagnosed annually, affecting about five people per 100,000. While age (most common between 55-75) and male sex are risk factors, environmental and occupational exposures are increasingly implicated in sporadic cases. Firefighters' repeated intense physical demands and chemical exposures align with patterns seen in other high-risk groups like military veterans and athletes.

• Progressive muscle weakness starting in limbs or bulbar region (speech/swallowing).
• Hyperreflexia and spasticity due to upper motor neuron involvement.
• Preserved cognition in most cases, distinguishing it from frontotemporal dementia variants.
• Treatments like riluzole and edaravone modestly slow progression; multidisciplinary care is key.

🎓 The Champion Insights Study: Pioneering Research

At the forefront of this investigation is the Champion Insights study, a ambitious nationwide effort officially opening enrollment in February 2026. Designed to enroll up to 500 participants living with ALS from high-performance populations—including firefighters, first responders, elite athletes, and military members—this study promises to uncover why these 'champions' face heightened vulnerability.

Led by the ALS Therapy Development Institute (ALS TDI) in partnership with Answer ALS and Augie's Quest to Cure ALS, the project receives substantial support from the Muscular Dystrophy Association (MDA) with a $200,000 grant and axeALS founded by former NFL player and firefighter Eric Stevens. The International Association of Fire Fighters (IAFF) plays a pivotal role in outreach, emphasizing the need for firefighter representation.

Participation is straightforward and remote: individuals provide in-home blood samples for genetic and metabolic analysis alongside detailed questionnaires on lifestyle, exposures, and health history. Researchers aim to identify biomarkers, genetic traits (like those tied to lipid metabolism and physical endurance), and environmental triggers. Early leaders like NFL Hall of Famer Steve Gleason highlight the study's potential to drive therapeutic breakthroughs.

"Understanding if there is a link between ALS and firefighting is a priority," notes IAFF's Racquel Cesnalis. Findings could shape presumptive legislation, enhancing benefits for affected firefighters and informing gear standards nationwide. For more details, visit the Champion Insights website.

Photo by Armin Narimani on Unsplash

Past Studies Laying the Groundwork

The Champion Insights builds on decades of epidemiological evidence pointing to elevated ALS risks in firefighters. A seminal 2010 Italian case-control study analyzing death certificates found firefighters had a two-fold increased odds ratio (OR=2.0, 99% CI 1.2-3.2) for ALS mortality, attributing it potentially to intermittent hypoxia from smoke inhalation.

More recently, a November 2025 study published in the International Journal of Environmental Research and Public Health examined ALS-related mortality among 33,122 World Trade Center (WTC) rescue workers, including FDNY firefighters. Comparing WTC-exposed to non-exposed cohorts from other cities, it found no elevated risk (SMR=0.44 in exposed vs. US population), but noted prior associations with firefighting. Factors like the healthy worker effect and superior medical surveillance may mask incidence rates. Full details are available in the PMC study.

US death certificate analyses and National ALS Registry data reinforce the pattern, with firefighters alongside welders and veterans showing 1.5-2x risks. These studies underscore the need for incidence-focused research like Champion Insights, as mortality data can underestimate prevalence due to improved survival through care.

Unpacking Potential Causes: Toxins at the Fire Line

What drives this disparity? Firefighters endure chronic exposure to a toxic cocktail during fires, training, and decontamination. Combustion byproducts like polycyclic aromatic hydrocarbons (PAHs), dioxins, and volatile organic compounds (VOCs) from burning plastics, furniture, and synthetics irritate nerves and induce oxidative stress, a hallmark of ALS pathology.

Heavy metals such as lead—found in batteries and older structures—accumulate systemically, crossing the blood-brain barrier to damage motor neurons. Per- and polyfluoroalkyl substances (PFAS), dubbed 'forever chemicals,' permeate turnout gear, firefighting foams (AFFF), and contaminated water runoff. While PFAS links to cancers and immune dysfunction are established, emerging data suggest neurotoxic effects aligning with ALS mechanisms like protein aggregation (e.g., TDP-43).

Other contributors include repetitive head trauma from falls or explosions, extreme physical exertion promoting inflammation, and hypoxia episodes reducing oxygen to neurons. Genetics may interact: carriers of ALS-linked variants could be more susceptible to these triggers. Prevention hinges on cleaner gear (PFAS-free alternatives), rigorous decontamination protocols, ventilation during overhaul, and annual neuro screenings.

• PAHs and dioxins: Neuroinflammatory agents.
• PFAS: Persistent, bioaccumulative, disrupts cellular function.
• Hypoxia: Mimics ALS neuron stress in lab models.
• Lead: Associated with motor neuron degeneration.

Human Stories: Firefighters Battling ALS

Behind the statistics are poignant narratives. John Heronime, a 16-year veteran of Gulf Shores Fire Rescue in Alabama, noticed weakness at age 43. Misdiagnosed initially, his ALS confirmation came in November 2024 at 45. Now relying on a cane and therapies at USA Health's Kelly Butler ALS Center, he credits multidisciplinary support—including drugs like edaravone—for maintaining independence.

Eric Stevens, a former NFL player turned Los Angeles firefighter, co-founded axeALS after diagnosis, raising millions for research. His story embodies the high-performance ethos Champion Insights targets. These accounts highlight delayed diagnoses (average two years), financial strains from early retirement, and the emotional toll on families, underscoring the need for proactive department policies.

IAFF-MDA partnerships provide resources like care coordination and Fill the Boot fundraisers, channeling proceeds to ALS initiatives. For IAFF updates, see their dedicated article.

Photo by Nubelson Fernandes on Unsplash

Protective Measures and Actionable Advice

While awaiting study results, firefighters can mitigate risks through evidence-based steps. Departments should prioritize PFAS-free gear transitions, as NIST research shows viable alternatives reduce uptake by 80 percent. Post-fire decontamination—wet wipes, change-out vans, soap showers—slashes PAH retention on skin by 50-70 percent.

• Wear SCBA (self-contained breathing apparatus) during overhaul.
• Conduct annual blood lead/PFAS monitoring via occupational health programs.
• Adopt fitness regimes balancing exertion with recovery to curb inflammation.
• Advocate for ALS presumptive status in state laws for disability benefits.

Early symptom awareness—persistent cramps, fatigue—prompts quicker neurology referrals. Researchers in research jobs at universities are developing neuroprotective agents; staying informed aids participation.

Looking Ahead: Implications for Policy and Research

The Champion Insights findings could catalyze change: expanded WTC Health Program coverage, federal PFAS phase-outs in gear, and targeted neuroprotection trials. IAFF-MDA committees push presumptive legislation in states like Illinois, where ALS isn't yet duty-related.

For those eyeing careers in occupational health or neurology, opportunities abound in clinical research jobs tackling these links. Share experiences on Rate My Professor to highlight expert educators in neuroscience.

In summary, the firefighter-ALS nexus demands action. Explore higher ed jobs in public health, follow higher ed career advice for research paths, or browse university jobs advancing ALS science. Your voice matters—engage in discussions to drive progress.