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> Winter 2003 > Articles

Agent Orange
A Deadly Member of the Rainbow
Printable Version

By Brandon Schneider

A lone man conspicuously saunters through the buzzing professional atmosphere, wearing a tattered, old fatigue shirt. He weaves through groups of scientists and administrators present at the National Academy of Science meeting, aloof and distanced.

“You know, you could have dressed better,” thought Dr. Linda Schwartz, a researcher at the Yale School of Nursing present at the conference. Prominent international groups were meeting to formalize a list of diseases attributable to Agent Orange, a defoliant used by the U.S. Military during the Vietnam War. The public was welcome, but a standard of dress was implicit.

Partway through a lecture, the man is called to the stage. He takes a poster from under his arm and unrolls it, showing an enlarged picture of a plane sweeping low to the ground spraying chemicals. Beneath it is a lone American soldier standing guard duty.

“See that plane?” he says. “That’s Agent Orange. See that soldier? That’s me.” The crowd is deathly silent.

Then he lifts up his shirt. His torso is disfigured, covered with gnarls and tumors. After a moment he reaches under the table and brings out a large jar, stating, “These are the ones they took out of me last year.”

Agent Orange was an herbicide used by the military to expose enemy supply trails hidden in the forests, eliminate foliage lining the coasts, and keep vegetation distanced from the perimeter of military bases.

The ecological ramifications were catastrophic: swathes of mangrove trees were destroyed, which normally serve as spawning grounds for various fish and shellfish. Agent Orange also washed into streams and the ocean, killing fish and embedding toxic chemicals in the surviving ones.

“I knew it would have adverse ecological effects, which it did – terrible ecological effects,” states Dr. Arthur Galston, Eaton Professor Emeritus of Botany and professor emeritus at the School of Forestry and Environmental Studies. “But I also knew the chemicals being used were potentially toxic to humans. This had never been adequately investigated.”

Galston turned out to be correct. An unavoidable byproduct of the synthesis of Agent Orange is dioxin – “one of the most poisonous substances ever created,” according to Galston. From 1965 to 1970, the U.S. Air Force sprayed 11.2 million gallons of Agent Orange and its contaminant over an area of land equal to two-thirds of the state of Massachusetts. It was the largest chemical warfare program in history and remains so.

Dioxin causes cancers, skin diseases, and severe fetal malformations, and is suspected to cause a slew of other diseases. There are an estimated one million Vietnamese either suffering from cancers or born deformed, allegedly as a result of exposure to dioxin.

Through much pressure, as the effects of Agent Orange became better understood and public opinion turned against the war, Agent Orange was banned by an Executive Order from President Nixon in 1970. Much credit is due to the efforts of Galston, who had always strongly protested the war and use of Agent Orange.

Galston recalls, “I used to think that one could avoid involvement in the antisocial consequences of science simply by not working on any project that might be turned to evil or destructive ends. I have learned that things are not all that simple….The only recourse for a scientist…is to remain involved with it to the end.”

Galston’s determination to halt the use of Agent Orange was perhaps stronger than that of other outraged scientists – for it was his chemical that the U.S. Military modified and employed in Vietnam.

The Men From Fort Detrick

When Galston was a graduate student in plant biochemistry in the 1940s, soybeans were a new crop recently imported from China. For his Ph.D. thesis, Galston set out to discover a way to speed up the flowering and fruiting of soybeans.

He succeeded with 2,3,5-triiodobenzoic acid (TIBA), but there was one critical side note: if too high a concentration of TIBA were used, all the leaves would drop off the soybean plant. Excessive amounts cause the plant to synthesize and release ethylene, which activates an enzyme that digests the cell wall between the leaf and the stem.

“Serendipitously I had uncovered a very effective defoliant,” recalls Galston. “It was an unwanted side effect.”

Discovering a defoliant was not a groundbreaking discovery; different varieties have been used for decades in agriculture. Machines that pick cotton break down after ingesting too many leaves, so defoliants are often sprayed 48 hours before harvesting, allowing for more efficient picking.

In 1951, eight years after publishing the effects of TIBA, Galston was approached by researchers from Fort Detrick, the chemical warfare service center.

An aerial photograph of the Ho Chi Min trail after it was sprayed with Agent Orange.  Before the spraying, the trail was completely invisible from overhead.
An aerial photograph of the Ho Chi Min trail after it was sprayed with Agent Orange. Before the spraying, the trail was completely invisible from overhead. (Credit: Arthur Galston)

Since World War II, the military had been interested in exploring the capabilities of defoliants. Without them, enemy forces and fortifications could be hidden imperceptibly in the forest. The Allies suffered heavy casualties when storming some beaches in the Pacific, and attempts to shoot down the trees with ammunition were fruitless. Eventually, they looked to plant physiology.

The researchers at Fort Detrick read Galston’s article and used his compound as a prototype for devising more potent and efficient herbicides to use during combat. 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) were developed, and when mixed in a 1:1 ratio, they comprise Agent Orange.

The Toxin: Dioxin

Studies have exonerated 2,4-D and 2,4,5-T of toxic effects on humans. The problem lies in the minute quantities of dioxin produced in the industrial process. Dioxin derives from an unusual head-to-tail coupling of the same molecule. Heating more than necessary, as chemical manufacturers sometimes do for efficiency, exacerbates the problem by creating higher levels of the contaminant.

Whether the full effects of dioxin were understood at the start of the air campaign is not known.

“It was part of the ‘better days with chemistry’ time of American history,” says Schwartz. “The military had a pretty lackadaisical way of handling it. For example, people sprayed it indiscriminately on the bases to keep the growth down so they didn’t have to cut the grass. They edged with dioxin.”

Dr. Candice Ross of the University of South Alabama, who jointly researches with Schwartz, recalls soldiers playing with Agent Orange and spraying each other with it. “When the barrels of Agent Orange were empty, [the soldiers] split them in two and used them for barbeque pits.”

The disastrous human effects would come later. Dioxin intercalates between base pairs in DNA, causing a number of cancers, including soft tissue sarcoma, non-Hodgkin’s lymphoma, and Hodgkin’s disease. In tests on lab animals, it is extremely teratogenic (Grk. monster), causing abnormal growths. Stillbirths, malformations, cystic livers, and deformed limbs and kidneys have all resulted from exposure to dioxin.

“It was toxic at levels [in rats] which when scaled up to human levels meant that the Vietnamese people who were exposed to the sprays probably were ingesting toxic quantities,” says Galston.

Agent Orange, named for the colored stripe encircling the 55-gallon barrel holding the chemicals, was one of six herbicides used by the military. Different agents were suited for different tasks, such as Agent White, which targeted rice crops.

Fight Against ‘Eco-cide’

Much of the scientific community was in outrage by the defoliation campaign, and especially Galston, since his research was a stepping-stone in the development of the toxic herbicide mixture. “I thought it was a misuse of science – science is meant to improve the lot of mankind, not diminish it – and its use as a military weapon I thought was ill-advised.”

Problems such as these are faced all too often by modern scientists. Albert Einstein was in a similar predicament after aiding in one of the greatest developments of modern science: harnessing the energy of the nucleus. The ends to which the technology would be used are highly controversial, and Einstein actively condemned use of the atomic bomb.

Galston pressed President Johnson with letters signed by dozens of eminent scientists. Eventually, with pressure from many sides, the Department of Defense commissioned a report on the effects of Agent Orange that was published in 1969. Many of the carcinogenic and teratogenic effects were elucidated.

Now Galston had hard facts to petition the new Nixon administration, and through a coincidence of history, he had a keyhole. Lee DuBridge was the science advisor to President Nixon and had been president of the California Institute of Technology when Galston was an associate professor there.

“[I and a colleague] decided to call DuBridge on the phone and say, ‘Hello, Lee! We have this hot information; what are you going to do about it?’”

DuBridge met with Army scientists to review the information and was convinced the use should be halted immediately. He pressed the Secretary of Defense, Melvin Laird, who discussed the issue with the President, and in 1970 an Executive Order terminated the use of Agent Orange.

“I died in Vietnam, but I didn’t even know it.”

The damage had already been done in the six years Agent Orange was used in Vietnam. Veterans returned to America and began developing life-threatening diseases and begetting children with birth defects.

During the early and mid-1970s, growing numbers of veterans began to question the possible linkage between their diseases and exposure to Agent Orange.

Paul Reutershan was a helicopter chief who flew almost daily through clouds of herbicides and “watched the mangrove forests turn brown and die.” Despite the destruction he observed on the plants, he did not fear for his own life because he was told by the Army that Agent Orange was “relatively nontoxic to humans and animals.”

Upon returning home from Vietnam, Reutershan was diagnosed with cancer. In early 1978 he went on the “Today” show and stated: “I died in Vietnam, but I didn’t even know it.” He passed away in December of 1978, but not before founding Agent Orange Victims International (AOVI) and beginning a class action lawsuit to aid victims of Agent Orange exposure.

The federal government could not be sued because of the Feres Doctrine, which “precludes recovery against the United States for injuries that arise out of or in the course of activity incident to military service.”

A mangrove forest that has been sprayed with Agent Orange.  The edge of the sprayed area is clearly visible where it runs into the unsprayed mangrove trees.
A mangrove forest that has been sprayed with Agent Orange. The edge of the sprayed area is clearly visible where it runs into the unsprayed mangrove trees. (Credit: Arthur Galston)

The chemical companies were fair game, however, and a class action lawsuit was officially filed in May 1979 against seven manufacturers. A settlement was approved in January 1985 without trial and a fund of $180 million was made available.

Regulations on what types of cancers are valid or who gets compensation are still controversial.

“Dioxin is a carcinogen with known effects,” says Schwartz. “A veteran who has been exposed to Agent Orange with soft tissue sarcoma qualifies. But if he has a cancerous brain tumor, that doesn’t count because of the convoluted ways they’ve designed the criteria.”

Similarly, compensation can go to civilian women who served in Vietnam, or children born to to these women, but men must prove exposure to Agent Orange. “We havea double standard here,” says Schwartz.

An Air Force study concluded that no relationship existed between paternal dioxin exposure and birth defects. However, Dr. George Knafl, biostatistician at the Yale School of Nursing, and Dr. Schwartz have been performing a secondary analysis of the Air Force data without excluding any subjects and employing more powerful statistical tools, and they have found a correlation does exist. They hope their findings will spur further research, some of which could study the 50,000 biological specimens taken from Vietnam troops archived by the Air Force. Using modern technology and recent discoveries about the metabolism of dioxin, researchers could come to a better understanding of the effects of dioxin levels from samples colleceted over 20 years ago.

As for the state of Vietnam, the United States has not provided any monetary restitution. There are still areas of high concentration of toxins, where trees have not yet begun to re-grow.

Recently, Vietnamese and American scientists have met to formulate a plan of research regarding the effects of Agent Orange.

About the Author

BRANDON SCHNEIDER is a sophomore in Saybrook College and intends to major in biology. He likes animals very, very much.


Institute of Medicine (U.S.). Veterans and Agent Orange: Health Effects of Herbicides Used in Vietnam. Washington, D.C.: National Academy Press. 1994.


The writer is indebted to Drs. Arthur Galston, Linda Schwartz, George Knafl, and Candice Ross for providing extensive information to draw upon for the article.

Further Reading

Veterans and Agent Orange

Dioxin Advisories and Guidance

Dioxin in Depth.

Agent Orange Website.

Science Links

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