This week, those veterans, including Army combat medic Will Thompson, may finally get some answers.
Thompson was often the life of the party while stationed in Iraq in 2004.
Today, at age 43, he's an outpatient at Inova Fairfax Hospital in Virginia. The recipient of a double lung transplant, he is struggling to stay alive.
"I want to live as long as I can, and if this mask can give me a couple more years, then that's what I am going to do," he said.
Thompson says the issues began during his second Iraqi deployment near Camp Victory in 2009.
"We did notice a couple of times when I was Skyping with him, 'Why are you coughing so much?'" said his wife, Suzanne.
Thompson was initially diagnosed with pneumonia. But once back home in West Virginia with his wife and their two children, he saw his own doctor.
"He said, 'This is way worse than pneumonia. This is something else. Your lungs look like an 80-year-old smoker, coal miner,'" Suzanne said.
By the spring of 2010, doctors at Walter Reed National Military Medical Center had diagnosed Thompson with severe pulmonary fibrosis. Their biopsy revealed titanium, magnesium and iron in his lung tissue.
Suzanne Thompson called Dr. Anthony Szema, a professor at Stony Brook University School of Medicine, who has been analyzing dust from Iraq and its impact on veterans' lung function.
"I wanted to make sure he got some of Will's old lung tissue because I said, 'What happened to Will, happened to Will, and we can't change that. But if there's anything we can do to help other soldiers, we want to do that.'"
In March 2013, Szema told CBS News that dust from Camp Victory was "very toxic."
Fourteen percent of the veterans he studied return with some sort of lung complication.
This week, Szema will present the result of his team's analysis of Camp Victory dust to a Pentagon subcommittee.
"After one month of exposure of sub-lethal doses of this dust, we can see septic thickening or lung fibrosis in the mice lungs," Szema said. "So, if we give a larger dose, it will kill the mouse. Eventually in a human, that would lead to a lung transplant."
Suzanne Thompson says she has no doubt her husband's illness was contracted in Iraq.
"I truly believe this happened in Iraq. He was fine before he left. He was perfectly healthy," she said.
"I hope and pray that my husband will be here with me to grow old and gray," she said, fighting tears. "This has changed me by just taking each day at a time," she said.
The Pentagon told CBS News that "nothing is more important to us than the health and well-being of our people."
"We take seriously the concerns associated with exposure to airborne hazards and continue to study the possible long-term health effects of this type of exposure during deployments," said the statement from Pentagon press secretary Navy Rear Adm. John F. Kirby.
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