What can we learn from the U.S. military use of chemical warfare in Vietnam


Casualties do not end with the war. In the wake of the imminent threat of war, less conversation revolves around ecocide — a type of chemical warfare that indirectly harms people by silently killing the environment. By studying the defoliant use of the U.S military during the U.S.-Vietnam war, this paper aims to shed light on a silent chemical war raged upon the environment, humans, and their descendants. Besides, when a silent yet persistent chemical contaminates basic necessities, scientific and legal acknowledgements alone are restricted in bringing justice to the victims when the harm is done. Understanding the nature and consequences of chemical warfare and legally condemning chemical warfare on the environment can be preventive measures to avoid repeating history.

What can we learn from the U.S. military use of chemical warfare in Vietnam

There is no humanitarian weapon. Throughout history, people have justified the use of chemical warfare despite being aware or unaware of its doomed harms and consequences. During the U.S-Vietnam war from 1962-71, the U.S. military sprayed approximately 77 million liters of herbicides – widely known as “Agent Orange” for its orange-colored storage container – over 3.6 Million acres of South Vietnam and its border with Lao (Institute of Medicine (US), Board on the Health of Select Populations, et al.). Agent Orange, a defoliant, destroys plant-based ecosystems by escalating the growth of plant tissues and is synthesized by a mixture of an equal ratio of two phenoxy acids which creates a toxic byproduct called dioxin. The U.S. used Agent Orange as a warfare tactic to remove enemies’ covers and destroy enemies’ crops. According to few survivors’ accounts, the plants turned brown and withered within minutes, and only sugar cane and lemongrass survived the spraying campaign (Black). Such an “ecocide” is claimed to have not only impacted the wellbeing of Vietnamese, Lao population, the U.S. military personnel deployed in Vietnam but also their descendents. However, the attempts to recount what actually happened to the victims remain limited.

Dioxin contaminates the food chain through first negatively impacting the environment. A study was conducted on dioxin exposure from food in Bien Hoa city which airbase was used for the spraying campaign. The results indicated alarming levels of food contamination that exceed the daily permissible intake set by World Health Organization (WHO) (Tuyet-Hanh et al.). Dioxin is hydrophobic and lipophilic, which means once released into an ecosystem, dioxin stays away from water and sticks to fats and organic matter. Dioxin settles into sediment where it is taken up by aquatic organisms, which are then eaten up by fish that humans consume. It is estimated that dioxin contamination in fish can be exponentially higher compared to the

surrounding water (Tuyet-Hanh et al.). Not limited to fishery products, other fatty foods such as meat and dairy products can also easily absorb dioxin. Once leached into the soil, despite the inability to soak into plant roots, dioxin still persists in the soil. To illustrate, the time for dioxin in the topsoil layer to degrade half of its concentration in each stage can take from 9-15 years while the soil underneath it takes 25-100 years in each stage; A single Dioxin cleanup project is estimated to span 10 years and cost $450 millions (Tuyet-Hanh et al.; USAID). Not only through the contaminated food chain, dioxin as a lipophilic compound poses a threat to fetuses and infants as dioxin can pass through the placental membrane and adheres to breast milk which is fatty in nature (Mori et al.). It is also estimated mothers transfer a fraction of their fatty acids to their fetus during pregnancy (Lewis et al.). In a study on the breast-milk samples collected from 2011-15 in one of the Agent Orange hot spots, dioxin levels exceeding the WHO recommended level was identified (Hue et al.). Abstaining from breast-feeding children can lose the benefits of transferring maternal antibodies when the babies have yet to fully develop their immune system. Dioxin is not picky in choosing its victims. In the 1984 findings by the United States Centre for Disease Control, the offspring of male veterans involved in the Operation indicated the increased incidence of brain and spinal cord defects (Pilsner et al.). Dioxin accumulation in the environment is, therefore, an unwanted legacy for the present and future generations.

Studying long term effects of Agent Orange has limitations, from identifying the affected population, different sensitivities between humans and test animals, to the latency of diseases. For example, dioxin found in Agent Orange-affected areas, is also emitted from coal-burning and incomplete burning of PVC plastic waste (Institute of Medicine (US), Pope, et al. 335). In order to research if Agent Orange elevates dioxin concentrations, not from other sources, the affected population with their exposed durations and intensities must be identified first. Here,

characterization can be complicated due to dioxin persistence in the environment and their mobility up the food chain, especially when foods are not locally sourced (Stellman and Stellman). Now, characterizing a control group — from the general population with no prior exposure as the baseline measurements for comparison — can further be complicated. In Vietnam’s case, the North Vietnam residents, away from the Southern Vietnam where the spraying operation took place, were taken as a control group (Institute of Medicine (US), Board on the Health of Select Populations, et al.). Misclassifying the exposed and unexposed groups will result in incorrect estimates of association between dioxin exposure and diseases or birth defects. Similarly for U.S. veterans, the answer to which troops were more affected remains highly debated. The air force personnels were initially studied as the high-risk group. Later, the ground troops were examined due to their supposed troop movements across defoliated lands (Institute of Medicine (US), Board on the Health of Select Populations, et al.). Even the toxicity testing was primarily experimented on mammal species like guinea pigs. Although animal testing can be applied in deducting potential health effects of dioxin exposure in humans, the sensitivity among species varies. For example, guinea pigs are 5,000-10,000 times more sensitive to dioxins than hamsters (Institute of Medicine (US), Pope, et al. 335). When it comes to the more ethical, scientific advancements, testing on lab-grown, isolated, and specific human cells cannot fully explain how dioxin will behave once inside the living human body (Krewski et al.). In some cases, dioxin persists inside the fat tissues of humans in the stored form and causes “internal exposure” (Institute of Medicine (US), Board on the Health of Select Populations, et al.). The chronic exposure to dioxin does not show immediate effects. Indeed, human studies in Italy show dioxin to likely cause cancers only decades after the incident (Bertazzi et al.). To achieve strong scientific evidence is to hold the power on information, funding, technical

knowledge and capacity. The effort to study health consequences requires reconstruction of available historical records, qualitative studies — especially, in cases when the US flight records were classified and incomplete — and constant monitoring of environmental and biological specimens (Black; Institute of Medicine (US), Board on the Health of Select Populations, et al.). For an affected country recuperating from the shock of war, economic recession, underdevelopment, lack of public revenue, and limited technical capacity can restrict efforts to effectively study the effects of dioxin. Nonetheless, the journey to bring justice takes decades.

The costs of funding research, health consequences, environmental reparation, and compensations put a burden on upcoming generations. In a 2004 lawsuit against U.S. chemical producers by the Vietnam Association for Victims of Agent Orange/Dioxin (VAVA), the verdict concluded that the U.S. violated “no domestic or international laws” on chemical weapons (Phan Xuan Dung). The well-known arguments by the U.S. are that Agent Orange is not a toxic chemical but a defoliant and that the U.S. was not legally bound by the 1925 Geneva protocol to avoid using herbicides during the Vietnam war (Phan Xuan Dung). The evidence suggests otherwise. The 2006 systematic review and meta-analysis of Agent Orange studies – 40% were conducted in the U.S. – from 1966 to 2002 found a statistically significant association between Agent Orange and human birth defects with a high variability of results among the studied populations (Ngo et al.). Although the paper indicates the possibility of publication bias in all published studies on Vietnamese and non-Vietnamese populations, the effects on Vietnamese people who resided in and fed on food grown in the dioxin-contaminated environment cannot be fully compared to U.S. veterans. To this day, the U.S. only claims spinal defects as the effects of dioxin for its veterans (U.S. Department of Veteran Affair). On the contrary, Vietnamese are criticized for seeing “every birth defect in their country as being caused by Agent Orange

exposure” (Schmidt). Likewise, chemical manufacturers and the U.S government “would prefer that health problems in Vietnam never be linked conclusively to Agent Orange” (Schmidt, 2016). The US national academic press concluded dioxin studies as having “poor exposure characterization, failure to fully control for confounding influences on outcomes, and sample sizes that are inadequate to draw statistically meaningful results” (National Academies of Sciences, Engineering, and Medicine 15). In fact, sharp rises in the occurrence of birth defects were reported in either the Vietnamese population or veterans since before the end of the war (Cecilia). The issue is beyond hard science. In the U.S., veterans from the Vietnam war are eligible for compensation as long as a veteran bears one of the diseases “presumptively” caused by Agent Orange since the Agent Orange Act of 1991 (U.S. Department of Veteran Affair). The list contains neurodegenerative diseases like Parkinson, blood related cancers like leukemia, a variety of cancers, and common illnesses such as Type 2 diabetes, hypertension, and ischemic heart disease (U.S. Department of Veteran Affair).

Stop Ecocide Foundation has been pushing for ecocide to be amended as one of the five crimes that can be prosecuted by the International Criminal Court (ICC) although investigating non-members of the ICC including the U.S and Russia must be authorized by the UN security council (Spiegel). As Richard Falk, a legal scholar wrote, “An Ecocide Convention could help carry forward into the future a legal condemnation of environmental warfare” (Falk). Looking at the Vietnamese and war veterans’ struggle for more than 50 years (still counting), humans could learn a real life lesson on how resources and human lives could be costed through the own ecosystem they destroy. Lastly, however the legal system and science may acknowledge the victims born with disabilities and abnormalities as potentially caused by Agent Orange, a disability has already become a life-time casualty for its victims.


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