A few years ago, retired Maj. Wes Carter was picking his way through a stack of internal Air Force memos, searching for clues that might help explain his recent heart attack and prostate cancer diagnosis. His eyes caught on several recommendations spelled out in all capital letters:

“NO ADDITIONAL SAMPLING …”

“DESTROY ALL …”

“IMMEDIATE DESTRUCTION …”

A Pentagon consultant was recommending that Air Force officials quickly and discreetly chop up and melt down a fleet of C-123 aircraft that had once sprayed the toxic herbicide Agent Orange across Vietnam. The consultant also suggested how to downplay the risk if journalists started asking questions: “The longer this issue remains unresolved, the greater the likelihood of outside press reporting on yet another ‘Agent Orange Controversy.’”

The Air Force, Carter saw in the records, had followed those suggestions.

Carter, now 70, had received the 2009 memos in response to public records requests he filed after recalling the chemical stench in a C-123 he crewed on as an Air Force reservist in the years after the Vietnam War. He’d soon discovered that others he’d served with had gotten sick, too. Now it seemed he’d uncovered a government-sanctioned plan to destroy evidence of any connection between the aircraft, Agent Orange and their illnesses. And the cover-up looked like it had been set in motion by one man: Alvin L. Young.

Carter had gotten his first glimpse of “Dr. Orange.”

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Young had drawn the nickname decades earlier as an Air Force expert on herbicides used to destroy enemy-shielding jungle in Vietnam. Since then — largely behind the scenes — the scientist, more than anyone else, has guided the stance of the military and U.S. Department of Veterans Affairs on Agent Orange and whether it has harmed service members.

Young tested the weed killer for the Air Force during the war, helped develop a plan to destroy it at sea a decade later — a waste of good herbicides, he’d said — then played a leading role in crafting the government’s response to veterans who believed the chemicals have made them sick. For a while, he even kept a vial of Agent Orange by his desk.

Throughout, as an officer and later as the government’s go-to consultant, Young’s fervent defense hasn’t wavered: Few veterans were exposed to Agent Orange, which contained the toxic chemical dioxin. And even if they were, it was in doses too small to harm them. Some vets, he wrote in a 2011 email, were simply “freeloaders,” making up ailments to “cash in” on the VA’s compensation system.

Over the years, the VA has repeatedly cited Young’s work to deny disability compensation to vets, saving the government millions of dollars.

Along the way, his influence has spawned a chorus of frustrated critics, including vets, respected scientists and top government officials. They argue that Young’s self-labeled “investigations” are compromised by inaccuracies, inconsistencies or omissions of key facts, and rely heavily on his previous work, some of which was funded by Monsanto Co. and Dow Chemical Co., the makers of Agent Orange. Young also served as an expert for the chemical companies in 2004 when Vietnam vets sued them.

“Most of the stuff he talks about is in no way accurate,” said Linda S. Birnbaum, director of the National Institute of Environmental Health Sciences, part of the National Institutes of Health, and a prominent expert on dioxin. “He’s been paid a hell of a lot of money by the VA over the years, and I think they don’t want to admit that maybe he [isn’t] the end all and be all.”

Birnbaum, whose agency studies how environmental factors affect health, questions how Young’s training in herbicide science qualifies him to draw some conclusions. “He is not an expert when it comes to the human health effects,” she said.

Others complain that Young spent years using his government authority to discount or resist new research, then later pointed to a lack of research to undercut vets’ health claims.

“For really almost 40 years, there has been a studious, concerted, planned effort to keep any study from being done and to discredit any study that has been done,” said Jeanne M. Stellman, an emeritus professor at Columbia University. Stellman, a widely published Agent Orange researcher, has repeatedly clashed with Young and the VA.

There’s a reason. In an era in which the military and the VA are facing a barrage of claims from vets alleging damaging chemical exposures, from burn pits in Afghanistan to hidden munitions in Iraq, Stellman said Young provides a reliable response when it comes to Agent Orange: No.

Anyone who set foot in Vietnam during the war is eligible for compensation if they become ill with one of 14 cancers or other ailments linked to Agent Orange. But vets with an array of other illnesses where the connection is less well established continue to push for benefits. And those vets who believe they were exposed while serving elsewhere must prove it — often finding themselves stymied.

It’s not just the vets. Some of their children now contend their parents’ exposure has led to their own health problems, and they, too, are filing claims.

In recent years, Young, 74, has been a consultant for the Department of Defense and the VA, as well as an expert witness for the U.S. Department of Justice on matters related to dioxin exposure. By his own estimate, he’s been paid “a few million” dollars over that time.

“He’s an outstanding scientist,” said Brad Flohr, a VA senior advisor for compensation, defending the agency’s decision to hire Young in spite of the controversy surrounding his work. “He’s done almost everything there is. He’s an excellent researcher into all things, not necessarily just Agent Orange.”

In an interview and emails, Young defended his role. To date, he said, there’s no conclusive evidence showing Agent Orange directly caused any health problems, only studies showing a statistical association. It’s an important distinction, he says.

“I’ve been blamed for a lot of things,” Young said. He likened the criticism he faces to Republican presidential nominee Donald Trump’s smearing of “Crooked Hillary” Clinton after 30 years of public service: “They say, ‘Crooked Young.’”

Young said he believes most sick vets are simply suffering from the effects of old age, or perhaps war itself, rather than Agent Orange. It’s a point even critics say has some validity as vets have grown older during the benefits battle. His critics, he said, are as biased against the herbicide as he is accused of being for it. “Who’s an impartial expert? Name one for me, by all means.”

When Carter came across Young’s name, he knew nothing of the controversy that surrounded him. He also had no need for benefits related to Agent Orange: He was already receiving full disability compensation from the VA for a back injury suffered during the first Gulf War.

Reading the memos after his 2011 cancer diagnosis, it seemed clear there was a link between Agent Orange and illnesses plaguing those who’d flown aboard C-123s.

But to get answers — and to help others get benefits — he’d have to take on Dr. Orange.

“Herbicide’s orange, violets are blue, when I hear ‘dioxins,’ I’ll think of you.” – Undated farewell note from a colleague to Alvin Young, circa 1980s.

In the summer of 1977, a VA claims worker in Chicago took a call from the sobbing wife of a veteran claiming “chemicals in Vietnam” had caused his cancer. The woman mentioned a mist sprayed from above to kill plants on the ground. The claims specialist, Maude DeVictor, called the Pentagon and was transferred to Capt. Alvin Young, who knew more about the chemicals used in Vietnam than perhaps anyone.

By then, Young, who’d gained an appreciation for herbicides on his family’s farm, had a doctorate in herbicide physiology and environmental toxicology and had spent nearly a decade studying defoliants for the Air Force. In 1961, the U.S. began spraying millions of gallons of herbicides across Vietnam’s thick jungles. Then, in 1971, it halted the effort after the South Vietnamese media reported a surge in birth defects in areas where the chemicals had been used — a political decision, according to Young, who didn’t believe the claims.

DeVictor peppered Young with questions on the phone that day. Within weeks, she’d identified more than two dozen other vets who believed their contact with Agent Orange had made them sick. DeVictor prepared a memo on what she had learned and shared her findings with a reporter, spurring national media attention on Agent Orange for the first time.

“Dr. Young was very helpful. Without him, I wouldn’t have known anything,” said DeVictor. She was later fired by the VA; she claimed for speaking out about the herbicide.

Young publicly refuted many of the comments attributed to him — especially those suggesting Agent Orange might have harmed vets — and criticized media reports that he felt sensationalized the risks. But the episode was a turning point, moving Young from the Air Force’s internal herbicide expert to public defender of Agent Orange.

Over the next decade, as concern grew about the effects of Agent Orange, Young was repeatedly promoted to positions of increasing influence, despite public clashes with prominent politicians and some federal health experts. In 1980, an exasperated Rep. Tom Daschle, D-South Dakota, who later became the Senate’s Majority Leader, challenged Young’s testimony before a House subcommittee by rattling off recent studies and media reports that suggested vets had suffered because of Agent Orange. “I really find it somewhat interesting,” Daschle said, “that they are all wrong and he is correct.”

Alvin Young, the government’s oft-used Agent Orange consultant, speaks to the Armed Forces Pest Management Board in 2014. (Armed Forces Pest Management Board, via Flickr

Moments earlier, Young had said he didn’t doubt the competency of other authors, they just couldn’t match his 12 years of analyzing records. “It is a very complex issue,” he said.

Young’s genial, almost folksy style belied a resolute confidence that while his listeners’ opinions might differ, no one knew Agent Orange as well as he did.

In a 1981 Air Force research paper titled “Agent Orange at the Crossroads of Science and Social Concern,” Young questioned whether some vets were using Agent Orange “to seek public recognition for their sacrifices in Vietnam” and “to acquire financial compensation during economically depressed times.” The paper earned him an Outstanding Research Award from the Air Force’s staff college.

The same year, the Air Force assigned Young to serve as director of the VA’s new Agent Orange Projects Office, in charge of planning and overseeing initial research into emerging health claims. Here, too, he attracted congressional ire. Sen. Alan Cranston, R-California, warned the VA’s chief medical director in 1983 that Young’s dismissive comments about possible health risks might cause the public to doubt the “sincerity of the VA’s effort.”

Soon after that, the White House tapped Young to serve as a senior policy analyst for its Office of Science and Technology Policy, giving him broad influence over the nation’s policy on dioxin. Over the next several years, the Reagan administration was accused of obstructing, stalling and minimizing research into Agent Orange.

In 1986, another House committee faulted Young for undermining a planned study of chemical company workers exposed to dioxin. Young maintained that previous studies conducted by Monsanto and Dow of their workers “might have been enough,” the panel’s report said.

Young recently denied interfering with that research but took credit for helping to shut down a major Centers for Disease Control and Prevention study of Vietnam vets in 1987 that sought definitive evidence of a link between health issues and Agent Orange. Young said data on who had been exposed wasn’t reliable enough, though others argued that military records on spray missions and troop movements would have sufficed.

In the end, answering the question of who was exposed was taken out of the hands of the scientists. Under pressure from vets and their families, Congress passed the Agent Orange Act. Signed into law by President George H. W. Bush in 1991, it presumed that all vets were exposed if they set foot in Vietnam during the war or traveled in boats on its rivers. And it provided compensation for them if they had certain conditions linked to exposure.

In Young’s view, the vets won; the science lost. By his final years at the White House, he was tiring of the battle. Young said emotions had risen so high he began “receiving threats to my family, threats to me.”

Back in the U.S., the C-123s were repurposed for use in the Air Force reserves. Wes Carter flew aboard the planes while assigned to a Massachusetts base. He remembers an overpowering stench from a C-123 named Patches for its many patched-up bullet holes. (Matt Rota, Special to ProPublica)

Carter didn’t serve in Vietnam and thus wasn’t covered by the Agent Orange Act. His connection to the herbicide began in 1974, when for six years he served as a crew member on a C-123 as part of his reserve duty at Westover Air Reserve Base in Massachusetts.

During the war, C-123s criss-crossed southeast Asia, mostly ferrying troops and supplies. A few dozen were modified for spraying herbicides and insecticide. Back home, most were stripped of the spray gear, cleaned and put into service with the Air Force reserves.

For Carter, the planes were an exhilarating break from his civilian marketing gig — even though when they flew through rain clouds, water seeped into the cabins and they were always too hot or too cold. He often flew on a C-123 that had been nicknamed “Patches” because it was hit almost 600 times by enemy bullets in Vietnam — then patched up with metal. Over the years, he served as an aeromedical evacuation technician, flight instructor and flight examiner.

Even then, Patches’ former duties in Vietnam worried Carter and other reservists, who complained about the overpowering odor coming from it. But after an inspection, he said, “the wing commander assured us that the aircraft was as safe as humanly possible.”

Patches was sent in 1980 to the National Museum of the Air Force near Dayton, Ohio, where it was displayed outside because of its chemical odor. Then, in 1994, during a restoration attempt, Air Force staff toxicologists said samples from the plane showed it was “heavily contaminated” with the dioxin TCDD, an unfortunate byproduct of manufacturing Agent Orange. Later, other planes were also found to be contaminated.

But no one alerted Carter or any of the 1,500 to 2,100 reservists who’d flown them at least two weekends a month plus two weeks a year, often for years. Instead, most of the contaminated planes were quarantined in Arizona at Davis-Monthan Air Force Base, a sprawling airplane graveyard nicknamed “the Boneyard.” In 2010, at Young’s recommendation, they were destroyed.

One year later, when Carter learned he had prostate cancer, his best friend from the reserves found out he did, too. With a few phone calls, Carter quickly tallied five from his old squadron with prostate cancer. The sixth he called had died. His squadron commanders and others tied to the planes also had Agent Orange-related illnesses.

“Nearly two months into this project,” Carter wrote on a blog he kept, “it seems I have trouble finding crewmembers who don’t have AO-illnesses!”

“Many lessons can be learned from the history of the Agent Orange panic. One is that when a government offers presumptive compensation for diseases (as by the Agent Orange Act of 1991), many persons will show up to collect. Some will not even have any disease.” – 2006 article “The Agent Orange Fiasco,” co-authored by Alvin Young

Decades after the last of the military’s Agent Orange was supposedly incinerated aboard a ship in the Pacific Ocean, Army vet Steve House went public in 2011 with a surprising claim: He and five others had been ordered in 1978 to dig a large ditch at a U.S. base in South Korea and dump leaky 55-gallon drums, some labeled “Compound Orange,” in it. One broke open, splashing him with its contents. More than three decades later, House was suffering from diabetes and nerve damage in his hands and feet — ailments that researchers have associated with dioxin exposure.

Around the same time House came forward, other ailing vets recounted that they, too, had been exposed to Agent Orange on military bases in Okinawa, Japan.

The Pentagon turned to a familiar ally.

“I just heard back from Korea and the situation has ‘re-heated’ and they do want to get Dr. Young on contract,” one defense department official wrote to others in June 2011, according to internal correspondence obtained by ProPublica and The Virginian-Pilot through the Freedom of Information Act.

By then, Young had established a second career. From his home in Cheyenne, Wyoming, he and his son ran a sort of Agent Orange crisis management firm. His clients: the federal government and the herbicide’s makers — both worried about a new wave of claims.

After Cancer Diagnosis, Vet Refutes Government’s Agent Orange Expert — And Wins After the VA rejects his claim for benefits, an Air Force veteran challenges the findings of the government’s go-to Agent Orange consultant. Six years later he emerges the rare victor. Read the story.

In 2006, under contract for the Defense Department, Young had produced an 81-page historical report listing everywhere Agent Orange had been used and stored outside of Vietnam, and emphasizing that even in those places, “individuals who entered a sprayed area one day after application … received essentially no ‘meaningful exposure.’” Among the scholarly references cited were several of his own papers, including a 2004 journal article he co-authored with funding from Monsanto and Dow. That conflict of interest was not acknowledged in the Defense Department report.

In an interview, Young said the companies’ financial support essentially paid the cost of publishing, but did not influence his findings. He and his co-authors, he said, “made it very clear” in the journal that Dow and Monsanto had funded the article. “That doesn’t mean that we took the position of the companies.”

The Pentagon also hired Young to write a book documenting its history with herbicides. Published in 2009, the book made Young Agent Orange’s official biographer.

In 2011, facing the new claims involving South Korea and Okinawa, the Defense Department asked Young and his son to search historical records and assess the evidence. In bothcases, they concluded that whatever the vets thought they’d seen or handled, it wasn’t Agent Orange. Young’s son did not respond to a request for comment.

Alvin Young dismissed the claims of House and other vets from Korea, saying he found no paperwork that showed the herbicide had been moved to their base. “Groundless,” Young told the Korea Times newspaper in 2011.

In Okinawa, Young was similarly dismissive, even after dozens of barrels, some labelled Dow Chemical Co., were found buried under a soccer field. The barrels were later found to contain high levels of dioxin. But Young told the Stars and Stripes newspaper, they were likely filled with discarded solvents and waste.

Young never spoke to the vets in either case.

“Why would I want to interview the veterans, I know what they’re going to say,” Young told ProPublica, saying he focused on what the records showed. “They were going to give the allegation. What we had to do is go and find out what really happened.”

In 2012, Young’s firm was hired again, this time by the VA, in part to assess the claims of other groups who believed they’d been sickened by their exposure to Agent Orange. One was led by Carter, a man whose determination appeared to match Young’s.

“Mr. Carter,” Young recalled recently, “was a man on a mission.”

In recent years, various ailing vets recall coming in contact with Agent Orange outside Vietnam. Several say they were ordered to dig a ditch in South Korea in 1978 to bury 55-gallon drums of the herbicide. Alvin Young, a government consultant, was hired to investigate and labeled the claims “groundless.” (Matt Rota, Special to ProPublica)

From almost the moment Carter came upon Young’s name in the Air Force documents, he’d been consumed by the scientist’s pivotal role. He began documenting Young’s influence on a blog he’d set up to keep fellow C-123 reservists informed. “Memo after memo from him showed exquisite sensitivity to unnecessary public awareness … what he calls ‘misinformation’ about Agent Orange. Best to keep things mum, from his perspective,” Carter wrote in a July 2011 post.

An Agent Orange activist who heard about Carter’s efforts sent him an email exchange between Young and a veteran named Lou Krieger. Krieger had been corresponding with Young about herbicide test sites in the United States and had mentioned that he believed the controversy over the C-123 aircraft represented “another piece of the puzzle.”

In a flash of anger, Young had written back, “The only reason these men prepared such a story is that they are hoping they can cash in on ‘tax free money’ for health issues that originate from lifestyles and aging. There was no exposure to Agent Orange or the dioxin, but that does not stop them from concocting exposure stories about Agent Orange hoping that some Congressional member will feel sorry for them and encourage [the VA] to pay them off.

“I can respect the men who flew those aircraft in combat and who made the sacrifices, many losing their lives, and almost all of them receiving Purple Hearts,” Young wrote, “but these men who subsequently flew them as ‘trash haulers,’ I have no respect for such freeloaders. If not freeloading, what is their motive?”

Young’s response offended Carter. He pressed his Freedom of Information Act campaign with renewed vigor, requesting a slew of new records from the Air Force and the VA. He later filed lawsuits, with the help of pro-bono lawyers, against the agencies for withholding documents. The government eventually gave him the records and paid his lawyers’ fees.

Carter worked the non-military world as well, soliciting letters from doctors, researchers and government officials who had expertise with toxic chemicals, some of whom had clashed with Young in the past. Several responded with letters supporting his cause, even a few who worked for federal agencies.

The head of the Agency for Toxic Substances and Disease Registry, a part of the CDC, wrote in March 2013 that based on the available information, “aircrew operating in this, and similar, environments were exposed to TCDD [dioxin].”

And a senior medical officer at the National Institute for Environmental Health Sciences wrote, “it is my opinion that the scientific evidence is clear” that exposure to dioxin is not only possible through the skin but has been associated with a number of health conditions, including cancer, heart disease and diabetes.

Wes Carter in a recent photo outside his home in Fort Collins, Colorado, holding a replica of Patches, a C-123 he often flew. (Matt Staver, Special to ProPublica)

Carter also found support in Congress from Sen. Richard Burr, R-North Carolina, and Sen. Jeff Merkley, D-Oregon, who began writing the VA regularly to advance Carter’s cause.

He sent missive after missive filled with his findings and the letters of support he’d received to the prestigious Institute of Medicine, a congressionally chartered research organization hired by the VA to assess the science behind the claims of Carter and other C-123 vets. If the VA was going to grant them benefits, Carter realized, he had to first convince this group of researchers that he was right.

“It didn’t take long to realize that the VA had a lot of resources working against us and we found none working for us,” he said.

One of those resources was Young, whom the agency had given a $600,000 no-bid contract to write research reports on Agent Orange.

Young had approached the VA in 2012, offering to assess vets’ claims that they’d been exposed to herbicides outside of Vietnam and weren’t covered by the Agent Orange Act.

Over the next two years, Young and his son wrote about two-dozen reports examining issues such as whether vets who served in Thailand, Guam or aboard Navy ships off the coast of Vietnam could have been exposed. In most cases, they concluded exposure was unlikely. The reports buttressed the VA’s rejection of claims by members of those groups, just as Young’s Pentagon reports were cited to deny those of individual vets.

In November 2012, Young turned in the first of several reports discounting the claims of Carter and his group. “All the analytical and scientific studies suggested that if they were exposed, that exposure was negligible,” he wrote. Although some samples taken from the C-123s showed minimal traces of dioxin, it was nothing to be concerned about, Young wrote, since dioxin sticks to surfaces and was unlikely to affect anyone who came in contact with the planes.

Though Young dismissed the vets’ claims, Carter’s campaign clearly bothered him. In a June 2013 email to a VA staffer, Young criticized the Air Force for releasing all of his correspondence to Carter.

A couple months later he wrote: “You and I knew that the preparations of these investigative reports were going to show that in most cases the allegations are without any evidence. We can expect much more media interest as more and more veteran claims are rejected on the basis of the historical records and science.”

Young’s contract with the VA and emails were later disclosed to Carter as a result of his FOIA requests and a lawsuit against the VA. The emails showed that Young had also discounted the opinions of other experts, including the VA’s own researchers when they linked Agent Orange to prostate cancer.

“It is clear the VA researchers do not understand what really occurred in Vietnam,” he wrote in May 2013 to several VA leaders, “and that the likelihood of exposure to Agent Orange was essentially negligible.”

For a time, Alvin Young kept a vial of agent orange near his desk. His colleagues nicknamed him “Dr. Orange.” (Matt Rota, Special to ProPublica)

“All too frequently, environmental activists, the media, and policy-makers form the public perceptions of the risks of toxic chemicals in our environment, with little or no regard for the actual scientific findings.” –Alvin Young in a 2008 editorial in the journal of Environmental Science and Pollution Research

For three years, Carter and Young had circled each other. Carter in his blog and in at least one intemperate email; Young in dismissive reports and notes to the VA. Finally in June 2014, they were face to face in Washington D.C. where an Institute of Medicine panel would weigh the evidence to determine which man was right.

They lived just 45 minutes apart — Young in Wyoming and Carter in Colorado — but had never met. Now they sat next to each other to deliver testimony.

Carter, who was now in a wheelchair, told panel members that their task should be straight-forward: Did the evidence show — more likely than not — that he and his crewmates had been exposed? “I’m probably the only bachelor’s degree person in this room, but I know the airplane,” he said.

Young, who followed him, gave a rundown on the planes’ uses during the Vietnam War and their return to this country. He then defended the destruction of the planes, leaving out his role as the consultant who told the military to do it.

“Those aircraft had been out there for almost 25 years. How long do you maintain an aircraft?” he said, adding later, “Those aircraft had a stigma.”

Young had been at odds with the IOM before. An earlier panel had embraced a method to estimate troop exposure to Agent Orange, angering Young and his allies who didn’t believe it was possible.

But the hours-long hearing on C-123s, in which an array of experts spoke, ended with no hint of which way the panel was leaning. As the months wore on without a decision, Carter began to wonder if he had wasted the past few years of his life. “I wasn’t a grandpa or a retiree or a hobbyist or a churchman, the things that usually follow in retirement,” he said. “I was ill and I was tired. It’s a lot of money. Every time I went back to Washington, there goes another fifteen hundred bucks.”

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Finally, on a crisp January morning in 2015, the IOM was ready to announce its decision. Carter and his wife Joan had flown in and now they sat holding hands in a conference room. Joining them were VA and Air Force officials, members of the IOM staff and journalists. Four lawyers who had helped him showed up too, as well as supportive congressional aides. Young, the man who’d fueled his quest, wasn’t there.

At the front of the room, Emory University’s nursing school dean began to deliver the results of the institute’s report. Carter heard the words “could have been exposed,” and knew he’d won. “That was the moment that I really understood.” Carter and his wife squeezed hands, then hugged with happiness and relief when the meeting ended.

The committee had rejected Young’s position that the dioxin residue found on interior surfaces of the C-123s would only have come off with a chemical wipe, dismissing that claim as “conjecture and not evidence-based.” His argument that dioxin wouldn’t be absorbed through a crew member’s skin was also wrong, the committee determined, and appeared to be based on an irrelevant Dow-funded study of contaminated soil. Further, Young’s overall description of the chemical properties and behavior of TCDD, a dioxin contaminant, were “inaccurate.”

Joan Carter said it was her husband’s most meaningful mission, “a kind of a legacy of some good work, some definitive good work that he could leave behind.” It allowed him to help “a far greater circle of fellow veterans, most of whom he never met.”

Within weeks, Young protested to the IOM that it had “ignored important historical and scientific information … some material was misinterpreted, and there was a failure to focus on the science instead of who or what agency provided the information.”

The IOM stood by its findings, and several months later, the VA approved disability benefits for the ailing C-123 veterans. In a statement, VA Secretary Robert McDonald called it “the right thing to do.”

In an interview, Young said the IOM panelists got it wrong — a retort he’s used for decades whenever his findings have been challenged.

“Unfortunately,” he said, they “did not have a good handle on the science.”

After their service, many C-123s were retired to a sprawling graveyard for airplanes in Arizona. After Agent Orange residue was found on some of the planes, the Air Force ordered them chopped up and melted down in 2010 on the recommendation of Alvin Young. (Matt Rota, Special to ProPublica)

The IOM’s dismissal of Young’s findings has not dampened the military’s reliance on him.

The Pentagon once again has signed Young on as a consultant, this time to track where herbicides were used at bases in the United States.

Pentagon officials declined to answer detailed questions about Young’s work, including how much he’s been paid. Spokesman Lt. Col. James B. Brindle would only say that Young is the “most knowledgeable subject matter expert” on Agent Orange and that his personal views “are not relevant to the historical research he was contracted to perform.”

While the VA didn’t renew Young’s contract when it expired in 2014, a VA official said the department wouldn’t hesitate to hire him again if he was the most qualified person. Flohr, the VA senior advisor, said Young was chosen for his expertise — not his position on the vets’ exposure. “It was purely scientific, the research he did,” he said, “no bias either way on his part or our part.”

In a subsequent statement, the VA said it makes decisions on Agent Orange “only after careful and exhaustive reviews of all the medical/scientific evidence. … Our obligation remains to the veterans we serve.”

Young’s continued work for the government comes as a surprise to those who squared off against him a generation ago. “As a physician, as a dioxin scientist, as an Agent Orange researcher, as a Vietnam-era veteran, I’m just appalled by that personally,” said Dr. Arnold Schecter, who has written a major textbook on dioxin and who has feuded with Young.

Today, despite his loss to Carter, Young is unwavering in his belief that his research is “great.” Among his few regrets: Putting controversial opinions — such as calling C-123 reservists freeloaders — in emails that could be obtained through public records requests.

Young said he, too, was exposed to Agent Orange while testing the chemicals over the years, and in that way has a deeply personal interest in the research.

“Give me some credit,” Young said. “Hell, I’ve got 40 years working out there on these issues. I have a great deal of experience. … Am I wrong? I could be wrong. I’ve always said I don’t understand it all.”