The Navy’s 10th Virginia-class submarine, the USS Minnesota, is delivered in 2013 in Norfolk, Va. A new report by the Submariners’ Advocacy Group, a coalition of former sailors, documents chemicals and other hazards found aboard submarines. (Alex R. Forster/U.S. Navy)

WASHINGTON — A coalition of Navy veterans is seeking an expansion of health care and disability benefits for toxic exposures linked to gases, chemicals and biological contaminants aboard submarines.

The nonprofit Submariners’ Advocacy Group is also pushing for the Navy to release findings from extensive atmospheric studies on submarines’ sealed environments conducted more than 20 years ago that remain classified.

David Bozarth, president of the Submariners’ Advocacy Group, said his organization documented more than 150 toxins that sailors could encounter on submarines. Bozarth served aboard submarines as a ballistic missile fire control technician from 1978 to 1984.

The coalition published its findings in a 60-page report released Saturday to the U.S. Submarine Veterans Inc., which represents active, retired and veteran personnel. Copies of the report were sent this week to the Pentagon and Department of Veterans Affairs.

The report, “The Unseen Burden: Toxic Exposures and Health Impacts on U.S. Submariners,” points to long-term consequences of exposure to chemicals, gases and ionizing radiation that are “unique to submarine service.”

“In a sealed environment with continual exposure to multiple chemicals the human body is subjected to a complex interplay of stressors,” according to the report.

The Submariners’ Advocacy Group formed in April 2024 in response to studies and findings by the National Research Council (NRC) Committee on Toxicity and the Naval Submarine Medical Research Laboratory. Those findings and others are included in the advocacy group’s report, which is published on its website.

Submariners are exposed to a “toxic cocktail” of chemicals with a combined effect that may be more potent than a single exposure, according to the NRC.

Some of the hazardous exposures may include benzene, ozone and asbestos for sailors who served on older submarines. Monoethanolamine is a chemical derived from ammonia that is used to scrub carbon dioxide from the atmosphere in a submarine.

The Navy has established exposure guidance levels for many contaminants. The service also works with the NRC to review, adjust and develop exposure guidance levels for specific contaminants as necessary.

Stanley Martinez, a 67-year-old Navy veteran from Utah, is the chairman of the advocacy group. Martinez, a former chief petty officer who served on submarines for 16 years, said he believes the medical needs of former sailors like him often are overlooked.

“The problems of submariners are different from the rest of the military because of the unusual environment,” said Martinez, who was diagnosed with a heart condition, ocular migraines and seizures after leaving the military in 1992.

The Submariners’ Advocacy Group formally incorporated in Missouri after Martinez, Bozarth and other ex-submariners started sharing information they found about contaminants and hazards associated with nuclear radiation in the sealed environments. “We started this group because no other veterans organization was focused on the needs of submariners,” Martinez said.

Many crew spaces not directly involved in reactor operations are close to radiation sources. Certain compartments with high concentrations of hazardous chemicals pose greater risks, including the engine room, auxiliary machinery spaces and missile compartments.

Carbon dioxide levels are higher in a submarine environment. Elevated levels may amplify the toxic effects of contaminants in the air, according to the NRC.

The oxygen content on board submarines is lower than in the natural environment, Bozarth said. “We have less oxygen available to us on submarines,” he said.

A chemical byproduct of lubricating oil for submarine machinery also has been found in the air and in common areas of submarines, on eating utensils and even on the skin of sailors, according to the advocacy group’s report.

“The byproduct produces a yellow discoloration that shows up on walls, floors, cooking utensils, everything,” Bozarth said.

There are an estimated 300,000 veterans living today who served since 1947 in the Navy’s submarine force, also known as the “silent service,” according to the veterans group. They make up less than 1% of the overall veteran population.

The Department of Veterans Affairs denies veterans claims for service-connected ailments acquired from serving on submarines at a higher rate than other types of claims, according to the advocacy group. But some medical conditions may be diagnosed decades after hazardous exposures on board submarines, the group said.

“I had a hard time getting the VA at first to understand and recognize the problems I was having,” Martinez said.

In 2011, VA doctors diagnosed a growth right above the mitral valve of his heart, said Martinez, who had open-heart surgery to remove it. “The surgeon told me, ‘You either have this surgery, or you will not survive,’ “ Martinez recalled. “I could not walk without having to stop and rest. I was dying.”

Martinez received a 100% disability rating from the VA six months after the surgery. He has a service dog that alerts him when he is about to have a seizure.

Bozarth, 66, of Missouri, said he knows several shipmates who died from serious and rare diseases in the past two decades, including from amyotrophic lateral sclerosis, or Lou Gehrig’s disease, early-onset Parkinson’s disease and uncommon forms of cancer.

“I have been helping many submarine veterans with their VA disability claims by providing information and assistance to their veterans service organizations,” Bozarth said.

Bozarth said he believes there has been inconsistent follow-up by the Navy in addressing toxins aboard submarines.

Martinez said protocols for managing radiation and chemical exposures — including the use of protective gear — are stricter than when he served more than 30 years ago.

“The engineering, the hydraulics also are different,” Martinez said. “But the power plants haven’t changed. They’re only modified. You still have the reactor core producing ionizing radiation, and the warheads are basically the same.”

Nuclear submarines are powered by onboard nuclear reactors, and every crew member is issued personal radiation monitors that are regularly checked, according to the Navy. Policies limit the time personnel are in areas that pose a risk from radiation sources. Physical barriers prevent accidental entry into the reactor compartment.

Service members “stationed on nuclear-powered submarines are occupationally exposed to external ionizing radiation at very low levels, and radiation dose for each individual is closely monitored. Little is known about ionizing radiation risks of cancer mortality for populations with levels of cumulative ionizing radiation exposure this low,” according to a 2022 report in the National Library of Medicine.

The Submariners’ Advocacy Group is asking for greater coverage under the PACT Act for diseases and other medical ailments sailors may have experienced from toxic exposures aboard submarines.

Nuclear workers aboard submarines may qualify for presumptive disability benefits if they have certain conditions linked to radiation exposure during service.

The Submariners’ Advocacy Group also is pushing for more studies on the effects of chemicals and biological contaminants aboard submarines.

“As submarine veterans, we are fighting to make sure other submarine veterans are protected and get the health care and treatment they need,” Bozarth said.

“We are doing this because no one else is doing it,” Martinez said. “We are the only ones.”