Interdisciplinary Minor in Global Sustainability
Senior Seminar
University of California, Irvine June 1997 


AGENT ORANGE

by Duc Nguyen

Global Sustainability

3-04-97

In 1961, the United States began spraying herbicides in its military campaign to defoliate the jungles of southern Vietnam. Mimicking Smokey Bear, American pilots chuckled "Remember! Only you can prevent forests," as they dropped weed killers over target sites. But as research progressed, the true nature of the chemicals which they were spraying came to light. It is certainly no longer a laughing matter when it is realized that Agent Orange, a major herbicide used, could be as deadly to humans as it is to plants.

The military research of herbicides dates back to World War II (1). Ineffectiveness prevented them from being used in the war. By the late 1950’s, however, herbicides developed could defoliate a large variety of plants. Naturally, they were thought to be a great weapon in combating jungle warfare. Applied to the Vietnam War, herbicides were used to defoliate the jungle and to destroy crops. Defoliation stripped the jungle of vegetation. Left barren, it no longer provided camouflage for the Viet Cong, their supply routes and base camps which would be more prone to aerial attacks. Crop destruction denied the communists of local food sources. This forced them to divert more resources to provide and transport foods other regions. But just as important, crop destruction also weakened enemy morale and forced villagers to move to cities where they could be more easily controlled.

The program for spraying herbicides over Vietnam was code named Operation Trail Dust. It began in 1961 and peaked from 1967 to 1969 (2). Various methods were employed to systematically spray these chemicals. On ground, they were used by soldiers to clear the perimeters of their base camps. Riverboats were used to spray the riverbanks. Most damage to the jungle was done by air. The Air Force Operation Ranch Hand, as it was called, used C-123 cargo aircrafts and helicopters to drop the majority of the herbicides used.

There were many types of herbicides used by the United States in Vietnam. Each was named after the color of the 4-inch band painted around the 55-gallon drums in which it was contained: Agent White, Purple, Blue, Green, Pink and Orange. In all, 19.4 million gallons of herbicides were used, 60% of which were Agent Orange (2).

The effects of the sprayings on the jungle were immediately recognizable. Estimates show that six million acres or twenty percent of the entire land area of the Republic of South Viet Nam was covered with chemical poisons (3). The President of South Vietnam, Nguyen Van Thieu, announced that herbicides had destroyed 23% forests in his country. Scientists from the American Association for the Advancement of Science who visited Vietnam in 1970 reported that Bamboo had spread to reclaim forest floors that hardwoods once claimed. Nearly all trees of coastal mangroves were destroyed after one spraying and were not expected to return to their normal states for at least one hundred years (3).

The effects of the herbicides on humans were less obvious. Agent Orange is a mixture of 2 major compounds- 2,4-dicholorophenoxyacetic acid and 2,4,5-tricholorophenoxyacetic acid. By mimicking a natural plant growth hormone, auxin, these herbicides are able to induce plants to grow themselves past their natural levels of sustainability. They were first used in the 1940's in the United States to destroy weeds in grain fields, pastures and turf. By the 1960's, these herbicides had become an important method of controlling weeds. Unfortunately, it was unknown at that time that Agent Orange also contained one of the most lethal compounds known to man, dioxin.

Dioxin generally refers to a group of about 75 chemicals made of two benzene rings with substituted chlorines. They are by-products in the manufacture of chlorine products like Polycholrinated Byphenal oils or the burning of chlorine containing wastes such as PVC pipes. In the production of cholorophenoxy herbicides, they were unwanted chemicals that couldn't be removed (4). The mechanism by which dioxin causes damage at the cellular level is not exactly known. It has been postulated that dioxin may be stored in fat cells and is activated by internal stress to induce chromosomal and cellular damage. Whatever the case, the toxicity of dioxin is unquestioned. Even at extremely small levels, it has been proven to be a deadly poison. Animal studies have shown that guinea pigs could die by a single dose that weighs less than a billionth of their body weight. In mice and rats, low levels of dioxin have been reported to cause decreased weight, lowered reproductive rate and internal hemorrhaging. Studies have found that, when given an oral dose of 210 ng/kg for 78 weeks, rats developed increase incidences in liver, hard palate, and tongue tumors. In 1969, the extensive use of herbicides was halted after a National Institute of Health report concluded that dioxin caused stillbirth in mice. The last herbicide operation was flown two years later.

The cessation fo the use of herbicides had come too late. By then, thousands of American soldiers and countless Vietnamese villagers had already been exposed to dioxin. Americans who came in contact with this poison included those who fought in the jungles, patrolled the rivers by boat, or participated in the spraying of herbicides. Many came home and were reported to have high increases in illnesses that were extremely uncommon in the general population. In contrast to animal studies, the cause and effect of dioxin on the veterans were not well determined because the amount of exposure is difficult to quantify among those who claimed to have been illed by dioxin.

But the correlation between dioxin and the reported illnesses are well documented. The Institute of Medicine had found that there is sufficient evidence of a statistical association between dioxin or herbicides and soft tissue sarcoma, non-Hodgkin's lymphoma, Hodgkin's disease, chloracne and PTG liver disorders. In scientific terms, statistical association means that there is an extremely low probability, less than 5%, that the events occurred randomly (5). A study by the Center for Disease Control found that there is a 50% higher rate of non-Hodgkin's Lymphoma among Vietnam vets than vets who didn't serve in Vietnam.

The Department of Veterans Affairs had provided special compensation for those who have become ill due to dioxin. Veterans who have chloracne, Hodgkin's disease, multiple myeloma, non-Hodgkin's lymphoma, porphyria cutanea tarda, respiratory cancers, soft tissue sarcoma, acute and subacute peripheral neuropathy and prostate cancer could qualify for monthly payments. The VA does not require that veterans prove that they were harmed by dioxin. It is assumed all personnel who served in Vietnam have been exposed to it (1).

Unlike their American counterparts, Vietnamese victims were exposed to dioxin on a long term basis. It is believed that the chemicals remained on the ground for 12 years. Each year, monsoon rains would spread the chemicals to uncontaminated areas by flushing it into streams and rivers. Many health experts believe that dioxin is in the food chain of southern Vietnam. It is carried in drinking water or by the fish caught in contaminated streams. But relatively little is known about the effects of dioxin on the villagers that were sprayed on. In part, this is due to their isolation from local authorities and hospitals.

Perhaps the most extensive long-term damage of dioxin was done to the second generation victims. It has been found that Vietnam veterans generally have lower sperm counts than those who didn't serve in Vietnam. In addition, their children have been more prone to birth defects pertaining to the skin, nervous system, heart, kidneys and oral clefts. Sudden Infant Death Syndrome is four times more likely in those born to Vietnam vets.

Difficult and premature births are a commonality at the Tu Du Obstetrical and Gynecological Hospital in Vietnam, which receives the bulk of the patients who received the largest amounts of defoliants in Vietnam. A hospital study in 1987 found that 30% of the 17,000 babies delivered at the hospital were either difficult of premature (3). The comparative rates of all south Vietnam is 10% and for the whole country, it is 8%.

Instances of birth defects are also extremely high at the hospital. Here, infants born without arms, legs, shoulders, and ears have all been found. Others have been born with gross cleft palates or were hydrocephalic. In 1987 alone, 40 infants suffered from neural tube defects, 40 from cleft palates, and 32 from malformation or absence of arms and legs. Every year since 1975, the hospital has been the site of 5 or more Siamese twins. Physicians at the hospital report that a deformed fetus is delivered every 2-3 days (3). A room at the hospital contains jars which store aborted and full fetuses with atrocious genetic defects. For us, they are reminders of what happens when one tinkers with mother nature.

SOURCES CITED AND URLs

(1) http://vva.gov/pressrel/agentsofs.htm

(2) EXECUTIVE SUMMARY: THE HERBICIDAL WARFARE PROGRAM IN VIETNAM, 1961 -1971

(3) Residual Dioxin in Viet Nam

(4) AGENT ORANGE by L. Vancil

(5) REPORT LINKS DISEASE TO HERBICIDES

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