The Department of Veterans Affairs has long resisted disability claims from servicemembers who said chemical residue left in Vietnam War-era planes used to spray defoliants over Southeast Asia caused them severe illnesses, including cancer.
This summer, a panel of independent scientists will try to determine whether those veterans could have been exposed to the toxins in defoliants, including Agent Orange, at a level that would be dangerous to their health.
If the panel, which hosts the first of a series of closed meetings and public hearings on May 15, finds a link, the servicemembers could be eligible for tax-free disability compensation of up to several thousand dollars a month.
That's something Wes Carter, a retired Air Force major, believes is long overdue.
"We've got some sick folks that are not allowed to go into VA," said Carter, a former Oregon resident leading the crusade who believes his prostate cancer and other disorders are due to his exposure to dioxin, a contaminant found in Agent Orange.
Carter served on C-123s in the Air Force Reserve as a medic from 1974 to 1980. The planes were used to spray millions of gallons of defoliants to destroy crops and eliminate jungle cover used by the North Vietnamese Army and the Viet Cong.
The military stopped the spraying by early 1971 over concerns that some defoliants contained compounds harmful to humans. The fleet returned stateside, but Air Force Reserve units continued to fly them on cargo and medevac missions until the early 1980s.
Over the years veterans who flew in those planes have been getting sick, and like many Vietnam veterans, they're blaming the defoliants.
Carter said he found out they still had dried herbicide residue in them after he was diagnosed in 2011 with prostate cancer, one of nearly 20 illnesses VA deems service-connected among Vietnam veterans due to possible herbicide exposure.
VA does not require Vietnam veterans to prove they were exposed to the herbicides. Instead, it presumes that they were if they develop certain diseases and disorders linked to those chemicals, and grants them disability compensation benefits.
Servicemembers who served on the planes after their return stateside need to "show on a factual basis that they were exposed in order to receive disability compensation," VA said in an email statement.
Carter was already receiving VA medical care and disability compensation for injuries he sustained on duty in the 1990s, but the agency denied his claim seeking Agent Orange-related disability pay in 2012.
A VA official wrote in support of the denial that medical studies showed it was unlikely that dioxin exposure would lead to adverse health effects. Carter said he's appealing, but that it can take years and he worries that at 67 and with cancer, that's more than he has left.
Other postwar C-123 veterans have successfully appealed similar denials. At least one C-123 veteran battling cancer was granted benefits without an appeal, but died a short time later.
Carter said the 2,100 veterans who served on the aircraft after the war should get the same benefit of the doubt.
Carter has amassed public documents showing that the Air Force canceled sales of several C-123s in 1996 and smelted them in 2010 over concerns that they were still contaminated with herbicide residue, even after they had sat in the Arizona desert for decades.
He has also garnered support from lawmakers and others, such as U.S. Sen. Jeff Merkley, D-Ore., Oregon Department of Veterans' Affairs Director Cameron Smith, Yale Law School researchers and several scientists.
Fred Berman, director of the Toxicology Information Center at Oregon Health and Science University, said VA "established new laws of chemistry" in denying the C-123 veterans' exposure claims.
In response, he and others co-authored a study in the April issue of the journal Environmental Research concluding that dioxin levels in the aircraft after the war were "likely to have exceeded several available exposure guidelines."
Dr. Terry Walters, deputy chief consultant in VA's Post Deployment Health group, said she understands the frustration, but VA is simply following the law. She said Congress provided the presumption for Vietnam veterans because there was no way to measure their actual exposure.
The difference for the postwar C-123 veterans, she said, is that there are dioxin measurements from the planes that can be used to make a risk assessment. "You have to draw the line somewhere," Walters said.
"What we're asking the Institute of Medicine to do is give us a scientific opinion of where that is," she added.
The institute, which has conducted congressionally mandated reviews to evaluate research on herbicides used in Vietnam, is scheduled to publish its conclusions in the fall.