Legislation passed over the summer providing lifetime healthcare and disability benefits to military personnel sickened by toxic smoke from massive trash-burning pits in Iraq and Afghanistan excludes tens of thousands of civilians who breathed the same air.

For more than a decade, the Department of Defense has acknowledged that air on many military bases in war zones was contaminated by toxic smoke from these burn pits: Football field-sized open air incinerators where military contractors disposed of everything from body parts and household trash to raw sewage and war-damaged vehicle parts, spraying it all with jet fuel and lighting it on fire.

The Honoring Our Promise to Address Comprehensive Toxics Act (Honoring Our PACT Act) covers military veterans who served on these bases, but excludes thousands of federal civilian employees sent to serve alongside them by t he Department of Defense and U.S. intelligence agencies, as well as the State Department, Treasury and the U.S. Agency for International Development. Sidelined by bureacratic wrangling in Congress, m any of these employees say they are stuck pursuing compensation through a process so onerous that it makes it impossible for them to get help.

"The evidentiary requirements... are in practice impossible to meet for those of us who got sick," Debora Pfaff, who was deployed to Iraq in 2009 as a Defense Intelligence Agency analyst, told Newsweek. Pfaff developed on her return a series of debilitating chronic ailments that have left her with the bone density of an 84-year old and only 56 percent lung function.

Anecdotal accounts compiled by Newsweek and survey research by the Rand Corp., a think tank with historic ties to the U.S. military, suggest that a growing number of deployed civilians and contractors are developing many of the same chronic conditions and ailments as military personnel: They range from cancer and respiratory disease to immune disorders.

In a statement, the defense department said it provides civilians with advisers to help navigate the injury compensation process but acknowledged their health is more difficult to track because they use private medical providers for most of their care.

The White House did not immediately respond to a request for comment.

For veterans, the PACT Act signed into law by President Joe Biden Aug. 10 slices through the red tape at the Department of Veterans Affairs (VA), relieving them of the burden of proving that their chronic illness or disability is the direct result of exposure to toxic burn pit smoke.

Biden has said he believes there might be a link between his son Beau's exposure to burn pit smoke while serving in Iraq and his 2015 death from brain cancer. But the scientific uncertainty about the causal link is an example of the bind that many veterans found themselves in before the passage of the PACT Act.

Now, if military veterans get sick from any one of a list of conditions known to be caused by toxic exposure (including the brain cancer that killed Beau Biden), they get a "presumption" that the illness is service-related. And that entitles them to lifetime healthcare and possible disability compensation payments at taxpayer expense.

But the civilians who served alongside them are left applying for benefits from the Office of Worker's Compensation Programs, or OWCP, an agency within the Department of Labor. The agency administers the Federal Employees' Compensation Act, setting strict standards claimants must meet to qualify for compensation. Specifically, for employment-related illnesses such as toxic exposure, the regulations require that claimants prove their condition was directly caused, aggravated, accelerated or precipitated by the conditions of their employment.

But Pfaff and others who've been through the claims process say the burden of proof is impossibly high because no one kept track of everything that was burned in those pits.

The claims process for federal civilian employees is also complicated by the dearth of medical professionals who can diagnose a link between their illnesses and the burn pits. It took Pfaff 11 years — though the claim she eventually filed was denied.

"It's an alphabet soup," Pfaff said of the diagnoses she got. She ticks them off: "POTS, Postural Orthostatic Tachycardia Syndrome," which causes brain fog, rapid heartbeats, lightheadedness and even fainting if she has to stand for long periods. "MCS, Multiple Chemical Sensitivity," which makes the body's immune system hyper-sensitive to certain chemicals, such as formaldehyde, frequently given off by new furniture and carpeting. "Anytime they replaced the carpeting or brought new furniture into the office, I would get headaches, fatigue and a runny nose." "SAD, Small Airways Dysfunction," which has almost halved her lung function. "GP and OP, gastroparesis and osteoporosis," a partial paralysis of the stomach that makes her unable to digest fiber and a degenerative bone disease that has left her with the bone density of a woman twice her age and caused a succession of fractures. "Oh, and fibromyalgia and chronic sinusitis," she said.

Several of Pfaff's conditions are on the list of illnesses covered by the PACT Act.

"It didn't matter ... that I was a perfectly healthy 31-year-old before I went to Iraq for five months and that within two weeks of coming home, I started to develop a slew of chronic ailments," she said. "I wasn't sick before I deployed, I was exposed to toxic chemicals, and now I'm sick."

The claims process required Pfaff to prove exactly which toxins she was exposed to, in which concentrations, and for how long – as well as the precise causal link between that exposure and her symptoms.

"Maybe that works for a workplace chemical spill, but in the case of a burn pit, no one can possibly know that," Pfaff said. "No one was keeping any records of what went into the burn pits."

Pfaff was lucky in one way. Joint Base Balad, in Iraq's notorious Sunni triangle, where she was deployed, actually had an air sampling program at the time she was there, so she was able to provide a definitive list of toxins to which she'd been exposed, and their concentration in the air she was breathing. But she couldn't prove causation.

Pfaff found "the most qualified person I could" – a research toxicologist who had worked for both the VA and the Environmental Protection Agency – to support her contention that her toxic exposure had caused her ailments.

In a statement, toxicologist Debbie Norris wrote that Pfaff's exposure to the toxins documented by the Balad air sampling program "resulted in significant respiratory, neurological, gastrointestinal, and cardiovascular dysfunction."

There was, she concluded, "a very high level of certainty" that Pfaff's exposure to these chemicals "caused her neurological and other health conditions."

Nonetheless, OWCP rejected the claim "because she [Norris] had a PhD in toxicology, rather than being a healthcare professional," Pfaff said.

Norris could not be reached for comment. OWCP Director Chris Godfrey told Newsweek in a statement that his office "routinely reviews current policy and procedure to promote timely, appropriate and accurate delivery of benefits to claimants who are injured or become ill on the job."

Several civilians who spoke to Newsweek said it is so hard to prove a causal connection that they didn't bother to file claims even though they got sick after their deployments.

"I was a marathoner, now I have asthma," one former State Department employee told Newsweek. He asked for anonymity because he's not cleared by his current employer to talk with the media.

He was deployed to Iraq and Afghanistan multiple times in the seven years after 2009. But without a pre-deployment baseline — a medical examination showing his lung function before he was deployed — there isn't any way to prove his condition wasn't pre-existing.

In 2009, many State Department employees weren't given pre-deployment health assessments and none received them post-deployment as a matter of course, the former employee said. "If you had a health issue when you returned, you could could raise it, but they would TDY [temporary duty assignment] you for months at a time and there was nothing at all when you came back."

He believes his asthma, and the "horrible allergies" he also developed since his deployment, are linked to his toxic exposure.

After deployments, "I would wake up at night coughing up this crud," he said.

The U.S. government doesn't know how many civilians it sent to serve in war zones during the two-decade long war on terror, said Molly Dunigan, a senior political scientist at the RAND Corp. think tank, And it doesn't collect any consistent data about their health, either.

But she conducted a 2013 survey of civilian contractors deployed to the Iraq and Afghanistan war zones in support of U.S. operations. Although the 660 respondents overall reported being in good health, nearly 40 percent reported at least one physical health problem they believed to be service-related.

The most common kind of physical health problem was orthopedic injury, reported by 11 percent, but the second most common kind, reported by more than 7 percent, was respiratory illness. Other ailments they self-reported that might be linked to toxic exposure included skin conditions (nearly 3 percent) digestive problems (2 percent) and cardiac or circulatory issues (nearly 2 percent).

In other words, Dunigan said, as many as one in six of the respondents self-reported suffering a service-related physical health problem that might be linked to toxic exposure.

The DOD says that 3.5 million military personnel were deployed to war zones overseas during 2001-21, but doesn't have number for contractors.

The PACT Act represents a rare bipartisan agreement in a Congress widely seen as the most divided in recent history.

It is also the fruit of a four-year campaign led by the sick and dying victims of toxic exposure and their families, who had unsuccessfully applied for VA benefits.

"Before the PACT Act was passed, nearly 8 in 10 veterans that applied for VA disability benefits because of burn pits or other toxic exposure got turned down," said Tom Porter, executive vice president for government affairs at the Iraq and Afghanistan Veterans of America (IAVA), a non-profit that advocates for veterans of the war on terror.

Porter himself developed asthma after his deployments, though his symptoms are manageable. But for too many veterans, he said, the campaign to get toxic exposure legislation passed became a race against time -- an increasingly desperate rush to get the care and benefits they needed before they succumbed to their symptoms.

Porter's organization was part of a coalition of more than 30 veterans service and advocacy groups that came together four years ago to push for legislation. Over the next three years, a slew of bills addressing toxic exposure from burn pits and other sources were proposed in the House and Senate.

One such bill, sponsored last year by Sens. Kirsten Gillibrand, D-NY and Marco Rubio, R-Fla, included language that sought to amend the legislation governing worker's compensation programs, so that civilian deployed personnel would enjoy the same presumption as their military counterparts.

But none of the bills made any progress until last year, when the issue was taken up by the chairmen of the Veterans' Affairs Committees in both the House and the Senate. However, federal civilian employees aren't within the veterans committees' jurisdiction, so legislating for them would have meant involving other committees.

Including the language on civilians "would have killed the bill," a Congressional staffer said.

In the Senate, proposals amending the worker's compensation program would have involved the jurisdiction of the Health, Education, Labor and Pensions and Homeland Security and Governmental Affairs committees. In the House, the Committee on Education and Labor and the Oversight and Government Reform Committees would have been involved, the staffer said. If they'd been included, the bill's supporters would never have been able to push it through in time "because [it] would have gotten mired in multiple committee jurisdictions."

The PACT Act: A good start

Advocates, such as Mark Jackson of the Stronghold Freedom Foundation, say they aren't giving up.

The PACT Act was "a good start," he told Newsweek, "But there's a long way to go. The government promised to look after us and our families."

The foundation is a non-profit that advocates for victims of toxic exposure who were deployed to Karshi-Khanabad, or K2, a Soviet-era airbase in Uzbekistan that was the logistics hub for special forces operations in Afghanistan between 2001 and 2005. In addition to burn pits, those at K2 were exposed to radiation, volatile organic chemicals and the remnants of Soviet chemical weapons, according to congressional investigators.

The Department of Defense says 15,777 service members were deployed to K2, but doesn't have numbers on civilian deployments, according to Jackson.

"There were a lot of DOD civilians there, from MWR [Morale, Welfare and Recreation] teams and the Army Corps of Engineers and other places, but we don't know how many," he said. As on every other U.S. military base there were also contractors, including many from countries such as Indonesia and the Philippines who did janitorial and other menial jobs. "Who was it who cleaned the toilets, did the laundry, served the food?" said Jackson, calling them "an invisible population."

"Everyone lived on the base, everyone breathed the same air," he said.

The foundation is seeking a permanent full time executive director and expects to resume lobbying in Congress next year, Jackson said.

"There's a lot of work still to do," he said, highlighting the issue of the families of veterans who were denied benefits and who died before the PACT Act passed. Like civilians denied worker's compensation, he said, "They get nothing."

"A lot of people got left behind," he said.

A career senior official who worked on toxic exposures during the Trump administration acknowledged that there was unfinished business with regard to government civilians.

"Unfortunately, it is extremely difficult to determine the exact numbers and locations of government civilians who deployed," he said, unless the White House Office of Management and Budget or the defense department launched a study to determine how many civilians were deployed and where.

Lizzie Landau, a spokeswoman for Gillibrand, who wrote the original bill covering civilians, said the senator's staff were "reviewing options and looking to identify potential solutions." Rubio's office did not immediately comment.

Meanwhile, Porter said, the science on toxic exposure is still developing, and the U.S. military is still using burn pits.

The DOD has policies and guidelines designed to limit their use, and on larger bases in Afghanistan, for example, it sought to build and operate proper incinerators. But as Porter pointed out: "In a 25-strong combat outpost in the mountains, you're not going to bring an incinerator up there with you. And you're not going to try and haul your trash back to a base with an incinerator. You're going to burn it there in the mountains. So as long as we're sending young men and women to war, they're going to be burning trash."

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