A new study has found Vietnam veterans exposed to defoliant Agent Orange have a considerably greater risk of developing prostate cancer, especially the most aggressive form of the disease. These findings are the first to show a relationship between the now-banned herbicide and this form of cancer. The team collected data on 13,144 Vietnam veterans, including 6,214 men exposed to Agent Orange between 1962-1971. Researchers found twice as many veterans exposed to the herbicide had developed prostate cancer, as opposed to the veterans who had not been exposed. Also, men who were exposed to the chemical were diagnosed with prostate cancer two-and-a-half years earlier than unexposed men and were four times more likely to be diagnosed with metastatic disease, or the spread of the disease to different organs.
Agent Orange was one of the “broad-leaf defoliants” used in the Vietnam War to destroy vegetation making the enemy easier to see. It is made of compounds that are known to be contaminated with the dioxin TCDD during production. Between 1962 and 1971, twenty million gallons of the chemical were sprayed contaminating both the ground and soldiers. In 1997, the International Agency on Cancer classified TCDD as a group 1 carcinogen, a classification that also includes arsenic, asbestos and gamma radiation.
The study’s lead author Dr. Karim Chamie, a resident physician in urology at the University of California, Davis, Department of Urology and the VA Northern California Healthy System, states the cancer the exposed veterans tend to get is the most aggressive form of the disease and has already spread, or is likely to spread, by the time the patient is seen by a doctor. The study has faced criticism from other doctors, most stating they are not totally convinced since the study relies on self-reported exposure to Agent Orange without objective proof of exposure and without knowing the amount of exposure. They also point out that all study participants who reported being exposed to the chemical were given thorough screening tests for prostate cancer meaning more cases would be found.
Dr. Chamie is trying to get the message out to all Vietnam veterans exposed to Agent Orange, as well as their physicians, since many do not go to VA (Veterans Administration) doctors and do not know the large risk factor for developing this cancer.