In 2008, Army Reserve Capt. LeRoy Torres returned home to Robstown, Texas, after a tour in Iraq. He went back to work as a state trooper with the Texas Highway Patrol.

Torres was a longtime runner. So when a suspect took off on foot one morning, Torres sprinted after him. But something was wrong. A burning sensation in his chest hurt so bad, it almost knocked him down.

"I was able to catch up, but afterwards, my goodness, I remember just — I laid on the ground, I was so exhausted," Torres says. "One of my buddies said, 'Man, what's wrong?' I said, 'Man, I don't know. I just feel really, really tired — my chest feels really tight. I don't know.' I couldn't catch my breath."

A few years later, Torres was diagnosed with a rare disease called constrictive bronchiolitis. Scars in his lungs block the flow of air.

He's among a growing number of veterans from Iraq and Afghanistan who believe their respiratory ailments are linked to burn pits. These were acres-wide mounds of waste near bases that contained everything from batteries to vehicle scraps to amputated body parts. The refuse was usually ignited with jet fuel.

"What people don't understand is just how large some of these bases really are — I mean, they're small cities," Patricia Kime tells NPR's David Greene. She's a health care and medicine reporter for Military Times. She says soldiers reported seeing dark plumes of smoke hanging heavy in the air.

"So these are open-air pits where they would light it on fire, and quite often they ran 24 hours a day," she says.

Proving A Link

One challenge for veterans is proving that burn pits are really the cause of their illnesses.

"People have said that it's this toxic mix of tiny, tiny dust particles that are not related to the burn pits, that are just related to the soil and the air in Iraq and Afghanistan, and often has contaminants in it such as aluminum and iron and titanium — so, heavy metals," Kime says. "The burn pits are the most obvious visual reason to blame, but it could be the dust, it could be chemical exposures, there could be a lot of other issues going on."

Last year, Congress ordered the Department of Veterans Affairs to set up the Airborne Hazards and Open Burn Pit Registry. So far, almost 50,000 veterans have signed up.

"It's not just necessarily burn pits. If you feel like you're sick as a result of deployment, you can sign on to it," Kime says. "And it's supposed to be used to track and to try to get some handle on the extent of the illnesses among this cadre."

A statement from the Department of Veterans Affairs in response to NPR's request for comment said, in part:

"At this time, there is conflicting and insufficient research to show that long-term health problems have resulted from burn pit exposure. VA continues to study the health of exposed veterans. The burn pit registry, which helps participants to become more aware of their health, while helping researchers to study the health effects of burn pits and other airborne hazards, is one of several research projects currently underway at VA."

Lawsuits Against A Contractor

And there's something else at stake here. One of the companies that operated the burn pits, KBR Inc., is facing lawsuits from veterans across the country. The company says if it's held liable, the U.S. military will have a hard time finding companies to do this kind of work.

"They believe that in future wars, these jobs will be done by contractors, and if they are not protected, it will be impossible for America to go into another war," Kime says.

A statement from KBR, in response to NPR's request for comment, said:

"At the limited number of bases where KBR operated burn pits in Iraq and Afghanistan, KBR personnel did so safely and effectively at the direction and under the control of the U.S. military."Government studies and reports show that military personnel deployed to Southwest Asia were exposed to many hazardous conditions, including the harsh ambient air. The government's best scientific and expert opinions have repeatedly concluded there is no link between any long term health issues and burn pit emissions."

But Capt. Torres disagrees. He and his wife, Rosie, founded Burn Pits 360 — a group that connects veterans who blame their chronic ailments on the practice.

"There's no doubt at all," he says. "I know this has been the result from the environmental exposure. There's no doubt."

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