There are many ways for dioxin, the toxic contaminant in Agent Orange, to enter the human body.

From food.  From breast milk. From the vapors.  From physical contact. 

"There is no doubt that during and after the war, many Vietnamese absorbed this very
toxic material [dioxin]. It is our belief from toxicological research and epidemiological
studies from many countries that this dioxin probably resulted in significant health effects
in Vietnam."

– Arnold Schecter and John Constable

The issue of whether or not exposure to dioxin has affected the health of the Vietnamese has been debated since the time of the war, when the first studies were released, showing that TCDD, the dioxin contaminant in Agent Orange, causes cancer and birth defects in animals. The International Agency for Research on Cancer (IARC), part of the World Health Organization, now identifies TCDD as a known human carcinogen. Animal studies have found that TCDD can cause also affect the immune, endocrine, reproductive, gastrointestinal, skin, cardiovascular and nervous systems.

While scientists debate over who was exposed to Agent Orange/dioxin and what the impacts may have been on human health, there is very little debate over the fact that up to several million Vietnamese were exposed over a period of at least a decade to TCDD. There is also little debate over the fact that that at the up to two dozen "dioxin hotspots" found around some of the former US military bases in southern Vietnam, a new generation of Vietnamese are continuing to be exposed to dioxin that can be traced directly back to the use of herbicides during the Vietnam War.  

“I have no future, no happiness.”

– Do Duc Diu, 12 of whose 15 children died before age 3, and father
of teenager with congenital brain seizures, Chicago Tribune, 2009.

The Numbers

To estimate the number of Vietnamese who have been impacted by Agent Orange/dioxin, it is necessary to separate the exposure into three potential modalities.  First is the past direct exposure to the population during the years of spraying over a period of ten years.  Second are those who may have been exposed to dioxin in the years during and immediately following the spraying through the contaminated soil and sediment and/or through contaminated fish and animals. Third are those who are currently being exposed to the TCDD that remains in the soil and sediment and is entering the food chain at the dioxin hotspots where the herbicides were stored, loaded onto airplane or spilled.  In addition, there are those in the second and even third generations who were not directly exposed but who are potentially being impacted due to their parent’s or grandparent’s exposure. It is this latter category of those potentially impacted by the herbicides where there is the greatest scientific debate.

The population of South Vietnam during the years of herbicide spraying was approximately 18 million.  Jeanne Stellman and her colleagues at Columbia University Mailman School of Public Health compared the spray records with census reports during the years that Agent Orange and the other herbicides were sprayed in Vietnam, and estimated that up to 4.5 million Vietnamese were living in the 3,181 villages that were directly in the spray paths and were potentially exposed to the dioxin contaminated herbicides. In addition, approximately a million more South Vietnamese (ARVN) and North Vietnamese soldiers who were fighting in southern Vietnam during the war were potentially exposed as they traveled through the sprayed areas. 

Unfortunately, there are not any firm figures for the number of adults who suffer from or have already died from illnesses associated with exposure to Agent Orange/dioxin. We also do not know for sure how many children and youth have disabilities that may be attributed to their parents’ or grandparents’ exposure to the herbicides. The Vietnam Red Cross estimates that 3 million Vietnamese have been affected by Agent Orange, including 150,000 children born with birth defects. However, this estimate is based on figures from a survey from the late 1990s, and is in need of revision.

The Vietnamese authorities identify Agent Orange/dioxin victims as those:

1. Having direct or indirect contact with toxic chemical/dioxin:

– People who lived or were in the military service in South Vietnam from
   1961 to 1980.

– People who have lived or worked in areas with high concentrations of dioxin
   (i.e., near Da Nang, Bien Hoa and Phu Cat airport)

– Offspring of such people

2. Suffering one or more of the following diseases:

a)  Soft Tissue Sarcoma
b)  Lymphoma Non-Hodgkin
c)  Hodgkin’s Disease
d)  Chloracne
e)  Respiratory Cancer
f)   Prostate Cancer
g)  Multiple Myeloma
h)  Spina bifida
i)   Porphiria Cutanea Tarda
j)   Peripheral Neuropathy
k)  Type 2 Diabetes
l)   Reproductive Abnormalities (in people who contact with toxic chemical/dioxin or
     the wife, daughter, daughter-in-law or granddaughter, granddaughter-in-law of
     people who contact with toxic chemical/dioxin).

m) Liver Cancer
n)  Neurological Defects
o)  Birth Defects (Children)

While there is evidence of the impact of Agent Orange on Vietnamese adults and children within Vietnam itself, one quarter that has not been heard from is Vietnamese exposed to Agent Orange who subsequently emigrated to the US or to other countries. 

One way in. A cow grazing on the dioxin hotspot in A Luoi Viet Nam. This area is now fenced off with a "Green Fence" of Honey Locust trees.

Agent Orange in the Viet Nam War: History and Consquences

by Prof. Dr. Le Cao Dai
(published in Vietnam - not currently available)

Linda Birnbaum (former EPA Toxicology Division Director) explains dioxin's impact on human health in a 2004 interview.