November 18, 2023

Agent Orange and Korean DMZ Veterans

By Kevin Mason

It is time to recognize Korean DMZ Veterans as a separate category rather than being a subset of their Vietnam contemporaries. Exposure to harmful herbicides is an example.

Five years ago in 2019, U.S. Senator Jerry Moran (R-KS) introduced S.576, the Fairness for Korean DMZ Veterans Act, as an attempt to expand the presumptive dates of herbicide exposure and its dioxins (TCDD) for veterans who served in and along the Korean Demilitarized Zone (DMZ). The bill had bipartisan support and was endorsed by the Veterans of Foreign Wars and the American Legion.

As the legislative process proceeded, the Fairness for Korean DMZ Veterans Act was rolled under the Blue Water Navy Vietnam Veterans Act of 2019. The outcome for Korean DMZ veterans was the expansion of presumptive exposure from April 1, 1968, through August 31, 1971, to starting September 1, 1967, an extension of seven months.

The Vietnam War overshadowed operations on the Korean DMZ. Few Americans realize that conflict was occurring in and along the Korean DMZ during this same period, referred to as the “second Korean War.”

During the Vietnam War, Agent Orange was diluted to a 9% solution (10 parts Diesel fuel to 1 part Agent Orange) and delivered through the aerial application as an aerosol spray on thick vegetation, including triple canopy jungle. Most of the herbicide mixture (70-90%) landed on the foliage and was subject to degradation through the photochemical process caused by sunlight. Only 1-6% of the 9% solution reached the ground. A Vietnam veteran's most typical contact with the herbicide was dermal, through droplet contact with the skin.

This information comes from Dr. Alvin L. Young’s work centered on the research and testing of Agent Orange at Eglin Air Force Base in late 1971. Dr. Young’s resulting book, The History, Use, Disposition, and Environmental Fate of Agent Orange, published in 2009, pertains mainly to Vietnam veterans. Dr. Young transferred most of his conclusions to the Korean DMZ. The four main elements his work centers on are:

Forest canopy and leaf area index
Photochemical degradation of TCDD (Dioxin)
Penetration to soil
Skin absorption.

Soldiers directly involved with herbicide operations along the Korean DMZ wrote the book Last Three Soldiers Standing: Defoliation of the Korean DMZ. In it, they describe the use of Agent Orange. Unlike the 9% solution sprayed from the air in Vietnam, it was at a 100% concentration, sprayed directly from vehicles carrying tanks of the material on grasses and shrubs along the Korean DMZ. The solution, ten times as powerful as that used in Vietnam, was quickly absorbed into the ground, negating most photochemical degradation caused by sunlight. According to testimony in one veteran’s VA appeals case, Dr. Mary-Ellen Taplin, M.D., a professor of medicine at the Harvard Medical School, stated that studies show estimates of the half-life in subsurface soil may range from 25 to 100 years.

Full-strength Agent Orange saturated the soil. These contaminated soils were subjected to excessive erosion, redeposition, and subsequent burial during monsoon rains. As the authors state: “The erosion of Agent Orange treated soils was so severe, that land mines would float out of the soil, be transported several tens of yards away downslope from their original locations, creating a hazard to patrols and work parties after every wet season.”

In contrast to dermal contact by Vietnam veterans, Korean DMZ veterans’ exposure years after the spraying was through inhalation and ingestion. Infantry soldiers tend to get dirty during patrol and other field duties while risking their lives in the Korean DMZ. They breathe and eat the dust, MREs, or drink from a dust-covered canteen. These physical tasks may be riding in an open vehicle during the summer on dusty roads, on patrol on a wet, muddy trail, digging fighting positions, or other subsurface soil disturbance.

One of the authors, former Lieutenant David K, Rogers, opines that throughout the Korean DMZ where Agent Orange and Agent Blue were applied, both dioxins and arsenic are present in toxic concentrations in some locations to a depth of three to five feet, well deep enough to delay the half-life, yet still a potential threat to soldiers serving long after August 31, 1971.

The summary of a Board of Veterans Appeals case captures David Rogers’ testimony: “[H]is expert opinion was based on research conducted by a group of researchers in 2017. Of key relevance was that dioxin has a proven half-life in surface soils of 5 to 15 years; and in shallow buried soils of 25 to 100 years, as documented by a plethora of scientific studies.”

Equating the use of herbicides along the Korean DMZ to that in Vietnam is fallacious. Herbicide employment differed in Korea. It does not account for the differences in climate, soil saturation amounts, flora, and contact methodology. Also, U.S. forces withdrew from Vietnam in the mid-1970s, where soldiers patrolled the Korean DMZ until October 1991. We continue to have service members stationed inside the DMZ at the Joint Security Area in Panmunjom. A study is required for long-term toxicity levels of herbicide dioxins in the soil and their effect on humans.

Over the past few years, Boards of Veterans’ Appeals have granted presumption of exposure to harmful herbicides outside the official presumptive dates, one as late for service from October 1978 to October 1979. However, these are case-specific and will not change the official presumptive dates established by the Veterans Administration.

It is time for our elected representatives, the Department of Defense, and the Department of Veterans Affairs to relook at herbicide use along the Korean DMZ and extend the presumptive dates for DMZ veterans past the current August 31, 1971 cutoff date.

If you want to thank these soldiers for their service take the time to contact your elected representatives and ask that they look into the situation.

Kevin Mason is a retired Army officer who commanded an infantry company stationed at Camp Greaves on the Korean DMZ from 1983-1984. Previously, he was the Assistant Operations Officer - Air (S3-Air) in the 3^rd Brigade, 2^nd Infantry Division; at that time, the 3^rd Brigade was responsible for operations in the U.S. Sector of the Korean DMZ.

Image: National Archives