From Wired:

Since returning home from Iraq and Afghanistan, an untold number of soldiers have come down with puzzling health problems. Chronic bronchitis. Neurological defects. Even cancer. Many of them are pointing the finger at a single culprit: The open-air “burn pits” that incinerated trash — from human waste to computer parts — on military bases overseas.

Pentagon officials have consistently reassured personnel that there was no “specific evidence” connecting the two. But now, only days after Danger Room uncovered a memo suggesting that Army officials knew how dangerous the pits were, an animal study is offering up new scientific evidence that links burn pits to depleted immune systems.

“The dust doesn’t only appear to cause lung inflammation,” says Dr. Anthony Szema, an assistant professor at Stony Brook School of Medicine who specializes in pulmonology and allergies, and the researcher who led this latest study. “It also destroys the body’s own T-cells.” Those cells are at the core of the body’s immune system, “like a bulletproof vest against illnesses,” Szema tells Danger Room. When they’re depleted, an individual is much more prone to myriad conditions.

For scientists, trying to establish a definitive connection between those diffuse health problems and the pits has been exceedingly difficult to do. Most notably because the Department of Defense, as a report issued by the Institutes of Medicine noted last year, didn’t collect adequate evidence — like what the pits burned and which soldiers were exposed — for researchers to draw any meaningful conclusions about the impact of the open-air incinerators. Szema’s study is only on 15 mice, so it’s by no means definitive. But it is an important first step.

Regardless, it’s becoming increasingly clear that Pentagon officials were aware of the risk posed by the pits. Another memo (.pdf), written by Lt. Col. Darrin Curtis in 2006 and obtained by Danger Room, warned of “an acute health hazard” to personnel stationed at Iraq’s Balad air base. “It is amazing,” he noted, “that the burn pit has been able to operate … without significant engineering controls being put in place.”

But as recently as yesterday, when asked about the leaked Army memo obtained by Danger Room (which cited a risk of ”long-term adverse health conditions” from the pits), Pentagon spokesperson George Little told reporters that “we do not have specific evidence that ties these kinds of disposal facilities to health issues.”

Perhaps not. But researchers just got way, way closer. A team, led by Dr. Szema at Stony Brook University, this week revealed to Danger Room the results of their ongoing investigations that are trying to directly link health problems to the air emitted by burn pits. And the results should cause those who served near the pits — which burned trash at most major bases in Iraq and Afghanistan during at least some period over the last decade — to be concerned.

More.