Jim McKassan vividly remembers his days serving at an airbase during the Vietnam War, including being assigned to help load cargo planes with large drums that were spilling a messy liquid.
"I had it all over my uniform. So I asked the lieutenant what it was, and he said it's a defoliant, like a weed killer? Yeah, but stronger. I said will it hurt you, ah no we've been spraying it on our own guys it won't hurt you," said McKassan.
Now, more than 40 years later, Jim has been diagnosed with prostate cancer, and doctors at the V.A. wanted to know more.
"At first they thought it was hereditary, then did background check found out I was an aircraft mechanic overseas. Asked me if I'd been involved with Agent Orange, I said I had," said McKassan.
Agent Orange, which was used to clear jungle foliage, has been linked to several types of cancer. But until recently, prostate cancer wasn't listed as one of them.
Doctor Ralph deVere White helped lead a study at U.C. Davis that looked AT 13,000 veterans.
The researchers found those exposed to Agent Orange were two and a half times more likely to develop prostate cancer, and four times as likely to have it spread or metastasize.
Numbers that didn't become apparent until veterans like Jim began to age.
"So the suggestion is that maybe not that Agent Orange cause prostate cancer, but it accelerates it," said Dr. deVere White.
Because its use effectively ended after the Vietnam War, studies of Agent Orange itself have been limited. But since prostate cancer can be detected early, the latest findings could trigger a large scale drive to test Vietnam era veterans for prostate cancer.
A strategy that already has support of McKassan, whose own cancer has stabilized since surgery.
"I meet friends that are vets, I tell them get PSA test prostate checked. They say I feel fine. I say that's great, but when you don't feel fine might be too late. I think government should step up to the plate," said McKassan.
The findings could have an impact on both the V.A. and private health insurance plans.
Close to 400,000 veterans are listed in the military's Agent Orange registry. According to researchers, about a third of them could be expected to develop prostate cancer.