PFAS Exposure and Liver Cancer Risk in Military Firefighters

Liver cancer is increasingly becoming one of the surging causes of cancer-related deaths worldwide, yet its risk factors are often misunderstood or overlooked, especially among those who serve in high-risk occupations, such as military firefighters. While responding to fires, fuel explosions, and various emergency situations on bases and airfields, these service members encounter toxic environments far beyond visible smoke and flames.

Firefighting foams were a staple in military firefighting operations for decades, particularly aqueous film-forming foam (AFFF). While effective at suppressing high-intensity fuel fires, AFFF has left behind an alarming legacy of contamination and potential long-term health consequences for service members. It is why, in recent years, growing attention has been focused on a class of synthetic chemicals also known as PFAS (per- and polyfluoroalkyl substances) or "forever chemicals". Although some studies are still exploring potential links, emerging research suggests that PFAS contamination may be associated with:

liver enzyme changes
metabolic disruption
fatty liver disease

Moreover, liver damage also includes an increased risk of liver cancer, particularly hepatocellular carcinoma (HCC). Additionally, PFOS is one of the most studied PFAS compounds and has been associated with changes in liver function and metabolism in some studies. PFOS (perfluooctane sulfate) is a highly toxic chemical with a strong association to HCC, the most frequently diagnosed type of liver cancer. For military firefighters, this connection raises urgent questions about:

occupational safety
long-term health monitoring
accountability

Data shows that military firefighters face a 20% to 30% higher risk of liver cancer stemming from their frequent exposure to PFAS in AFFF, occurring through:

skin contact with AFFF
inhalation of foam vapors and smoke
repeated use of large amounts of foam during training and emergencies

Severe Health Impacts After Many Years From Initial Exposure

The liver's primary function is to filter toxins from the bloodstream, but this also makes it highly susceptible to harmful chemicals such as PFAS / PFOS. Over time, accumulation of PFAS / PFOS can disrupt liver cell function and increase cancer risk. This is why these chemical compounds have been studied for their potential hepatotoxic effects, possibly causing chronic liver disease and altering the metabolism of:

amino acids
glucose
bile acid

PFAS? accumulate in the liver over time, potentially leading to cancer in years after initial exposure- though the timeline and degree of health outcomes vary widely in each individual case and are not fully established. The biological mechanism is that once absorbed into the bloodstream, PFAS molecules bind to liver proteins and cellular structures. One of the earliest effects of PFAS on the liver is fat metabolism disruption. Medical research has found associations between higher PFAS levels and nonalcoholic fatty liver disease (NAFLD) - a condition that increases inflammation and creates the premises of tumor growth.

What the Research Reveals

While research specifically on military firefighters is limited, studies show that exposure to PFAS and PAHs (byproducts of burning) from fires poses measurable health risks. During consulting the relevant CELSPAC-FIREexpo study, we found that this combined exposure produces measurable changes in liver-related blood markers, including cholesterol levels. Besides the health impacts, the study also highlights firefighters' occupational risks.

A 2019 study examined the link between PFAS exposure and NAFLD. It concluded that individuals with higher PFAS levels in their blood were more likely to show signs of liver damage, particularly fat accumulation. Consequently, researchers noted that PFAS can disrupt normal liver function and metabolic processes. While reviewing the findings and correlating them with a considerable number of veterans' toxic exposure claims, we saw that the association was especially strong for certain PFAS compounds, suggesting that not all PFAS have the same impact. We also noticed that, although the study does not establish direct causation, it strengthens the growing evidence base linking long-term PFAS exposure to chronic liver conditions like NAFLD.

In another study investigating PFAS and liver function, scientists found that these chemicals can activate key liver proteins involved in fat metabolism, cell growth, and inflammation. They reported that this activation may trigger biological processes leading to tumor development. Examined data show that PFAS exposure can disrupt normal regulatory mechanisms and contribute to cancer. We noticed that these findings may be relevant when evaluating long-term health outcomes in occupational exposure cases, including military personnel. Even though further human research is needed, the study adds important insight into how PFAS may contribute to liver cancer risk - valuable information for veterans' claims.

Early Warning Signs of Liver Cancer

Given that laboratory research suggests that PFAS may alter normal liver functions by perturbing how liver cells regulate essential metabolic processes, the health impact on veterans becomes more evident. As PFAS interfere with the body's ability to properly process and store fats, abnormal liver fat accumulation becomes the first hint of incipient liver damage. Researchers have also observed that PFAS can trigger oxidative stress and inflammation, both of which place additional strain on liver cells.

Moreover, PFAS exposure can further contribute to abnormal cell growth and division, creating an increased risk of liver damage and, over time, contribute to serious diseases, including cancer. Liver cancer can sometimes have known causes, but it can also appear with no underlying liver disease. Risk factors generally include:

chronic hepatitis
cirrhosis
inherited liver diseases
diabetes
fatty liver disease
long-term heavy alcohol use
exposure to toxins (PFAS)

Because most people don't have symptoms, diagnosis is difficult in the early stages. When liver cancer advances, specific signs appear, including:

unexplained weight loss
loss of appetite
upper abdominal pain
nausea and vomiting
general weakness and fatigue
abdominal swelling
yellowing skin and eyes
white, chalky stools

Considering that liver cancer is often misdiagnosed, veterans should make sure they have received the right diagnosis by consulting more than one medical expert. Liver cancer symptoms might not seem severe in the beginning, and many veterans tend to overlook and ignore the early signs. Military or civilian firefighters must be extra cautious with their health, as cancer is the number one cause of death among this occupational group. Liver cancer can be misdiagnosed as:

fatty liver disease
alveolar hydatid disease
hepatic hemangioma
peptic ulcer
gastritis
hepatitis
mononucleosis
cirrhosis

There are numerous ways veterans can receive a misdiagnosis when they seek medical assistance for their liver cancer symptoms, such as:

Physicians fail to properly examine or refer individuals for further investigations to a specialist.
Liver cancer symptoms are not correctly identified or are wrongly diagnosed.
Incorrect test follow-ups, or your test results are misread or misinterpreted.

A cancer that starts in the liver rather than spreading there from elsewhere is called primary liver cancer, and it has three main types:

Hepatocellular carcinoma (HCC) is the most common, and it starts in liver cells.
Intrahepatic cholangiocarcinoma (IHC) or bile duct cancer accounts for 10-20% of cases.
Hepatic angiosarcoma is a very rare condition, accounting for ~1% of cases, and it starts in the liver's blood vessel lining.

How the VA Verifies Veterans' Liver Cancer Diagnosis

Firefighting was classified by the International Agency for Research on Cancer (IARC) as a group 1 carcinogen - meaning it is carcinogenic to humans - partially due to exposure to harmful chemicals such as PFAS. However, chemical exposure is only one of the causes, because firefighters face a mixture of hazards, including:

combustion byproducts
diesel exhaust
contaminated dusts and materials

More than that, PFAS was found in turnout gear and AFFF, which is why it is critical for veterans who notice symptoms to inform the doctor about military service, firefighting duties, and known PFAS exposure. To establish a valid service connection for disability benefits and ensure the cancer meets specific medical criteria for 100% disability ratings, the VA relies on medical evidence from the treating doctor to establish a diagnosis of liver cancer. particularly HCC, through a combination of:

high-risk surveillance programs
advanced imaging techniques
tissue biopsy

Furthermore, to ensure accurate diagnosis, the VA often relies on specialized regional tumor boards. It's also conducting the largest liver cancer screening study to date, the PREMIUM trial, which compares ultrasound with abbreviated MRI for early detection in veterans with cirrhosis. A correct diagnosis is also grounds for initiating specialized, high-quality care, and it's often required for liver transplant eligibility. The VA can verify a liver cancer diagnosis using standard tests, such as:

blood work and liver function tests
imaging (ultrasound, CT scan, MRI)
ERCP (for bile duct cancer)
liver biopsy

An accurate documentation from VA providers is essential for service-connected claims. Veterans can support their VA disability claim by providing the following documents, which could relate to their claimed illnesses, or they could show that their rated disability has gotten worse:

VA medical records and hospital records
private medical records and hospital reports
supporting statements

Depending on the type of claim, former service members may gather supporting documents themselves, or they can ask for VA help to gather evidence.

VA Special Rules for Cancer

If veterans'?liver cancer is determined to be service-connected, the VA typically assigns a 100% disability rating while the disease is active, including during treatment and for six months afterward. After that, the VA schedules a C&P exam to assess whether the cancer is in remission. Ratings may then be adjusted based on any lasting effects, such as liver dysfunction, fatigue, or other long-term complications.

For military firefighters, it is especially important to document firefighting duties and exposure to PFAS to help establish and support a service connection. As of 2026, VA disability compensation rates for veterans without dependents are as follows:

0% - $0.00 per month
10% - $180.42 per month
20% - $356.66 per month
30% - $552.47 per month
40% - $795.84 per month
50% - $1,132.90 per month
60% - $1,435.02 per month
70% - $1,808.45 per month
80% - $2,102.15 per month
90% - $2,362.30 per month
100% - $3,938.58 per month

These rates are adjusted annually as the cost-of-living figures evolve. For the most current figures, veterans should consult the official VA compensation rate table.

If you plan to apply for VA disability compensation on paper, it's often helpful to first submit an Intent to File. This notifies the VA of your plan to apply, giving you time to gather supporting evidence while preserving your effective date, the point at which your benefits can begin. Filing an Intent to File may also make you eligible for retroactive payments starting from that earlier date. If you apply for VA disability compensation online, there's no need to submit a separate Intent to File. Your effective date is automatically established on the day you begin the application, even before you complete and submit it.

Offering Assistance for Veterans Filing AFFF Claims

For military firefighters facing a liver cancer diagnosis, understanding available options is critical. They may be entitled to benefits, compensation, and support, but taking action early can make a meaningful difference. Veterans who meet the eligibility criteria may file:

VA Claims: The VA is actively reviewing evidence to determine whether PFAS-related diseases, including liver cancer, may qualify for presumptive service connection under the PACT Act. Filing a claim now can help protect your eligibility as policies continue to evolve.
Legal Action: Military personnel and firefighters who developed liver cancer after exposure to AFFF may also have the right to pursue legal claims against manufacturers responsible for PFAS-containing products.

However, you shouldn't wait to explore your options; instead, you may be proactive and proceed to gather your service and medical records, document your exposure, and seek guidance to ensure your case is fully developed. We can help you make the first step�and secure the benefits and accountability you deserve by contacting you with legal specialists ready to take on your case.