Scientists have always concurred that exposure to Agent Orange leads to serious health maladies - a conclusion those responsible for the poison conveniently ignore.
The US government and chemical companies that produced Agent Orange say there is not sufficient proof linking the dioxin-laden defoliant to the grave health problems suffered by Vietnamese and Americans exposed to it, but scientific studies suggest exactly the opposite.
Monsanto spokesperson Bob Peirce told Thanh Nien Daily via email that decades of heath studies had "not conclusively demonstrated a cause-and-effect link between spraying of Agent Orange and the diseases that were evaluated."
Jill Montgomery from Monsanto responded similarly to a request for comment from the website CorpWatch in 2004: "Reliable scientific evidence indicates that Agent Orange is not the cause of serious long-term health effects."
But Dr. Arthur Schecter, a professor at the University of Texas School of Public Health who has spent decades studying the effects of Agent Orange both in Vietnam and the US, tells a different story.
"There has been proven illness from dioxin in Agent Orange in Vietnamese, especially birth defects," he told Thanh Nien Daily via email.
Peirce admitted that studies had found links between Agent Orange and health problems but he inferred that while Agent Orange was connected to medical issues via "association" it might not be linked by "causality."
Dr. Schecter was more to the point: "There is little or no doubt that dioxins cause health problems in lab animals and humans."
Dr. Wayne Dwernychuk, a former senior environmental scientist with Hatfield Consultants familiar with the history of Agent Orange, was able to elaborate further on Peirce's statement.
"The chemical industry and others with a vested interest in 'no statistically significant' correlation will always say the an 'association' does not necessarily mean an 'unequivocal' relationship between exposure and health effect. Semantics are the godsend of defense lawyers," he said. "To block, deflect, and simply confuse is the way of much of the justice system... and the chemical industry has used this approach ad nauseum on this issue."
Dow Chemical, one of the two largest manufacturers of Agent Orange along with Monsanto, did not return phone calls and email requests for comment on the issue.
Credible research, international standards
Speaking at congressional hearings on Agent Orange last year, US State Department representative Scot Marciel also denied evidence that Agent Orange caused human health problems.
"There are certainly disabilities in Vietnam and birth defects. I have seen them, too, and it is really heart rending. There is not very good scientific evidence about what caused it," said Marciel, deputy assistant secretary at the Bureau of East Asian and Pacific Affairs.
But at the same hearing, Dr. Vaughan C. Turekian, Chief International Officer of the American Association for the Advancement of Science, said the Institute of Medicine had found sufficient evidence between Agent Orange exposure and certain types of cancers, including soft tissue sarcoma, non-Hodgkinlymphoma, Hodgkin disease, and chronic lymphocytic leukemia, and chloracne.
"The EPA (Environmental Protection Agency) also released a report in 2000, concluding that dioxins are carcinogenic in humans and may cause adverse health effects including: immune system alterations, reproductive, developmental or nervous system effects, endocrine disruption, altered lipid metabolism, liver damage and skin lesions," he told the congressional Subcommittee on Asia, the Pacific and the Global Environment.
He was quick to point out that the studies only evaluated American war veterans, whereas such effects would pale in comparison to the Vietnamese people who remain in the affected areas and have suffered much longer-term exposure.
"These people continued drinking water with dioxin-laced sediment and eating fatty tissues fish from contaminated water sources... TCDD (2,3,7,8-Tetrachlorodibenzodioxin - a dioxin in Agent Orange) entered the food chain through consumption," said Turekian in written testimony submitted to the hearing.
Dr. Nguyen Thi Ngoc Phuong, director general of Ho Chi Minh City's Ngoc Tam Hospital, discussed similar findings at the same hearing.
"In 1970, the breast milk of mothers living in sprayed areas analyzed by biochemists in the US had more than 1,500 grams of dioxin, thousands of times higher than that in the US, Japan, Canada, and the standard level allowed by WHO," she said.
"[Vietnamese] Breast milk analyses done by laboratories in Canada and Germany still show a very high level of dioxin. Because of this, victims are increasingly millions of innocent, newborn babies, breast fed by their exposed mothers."
The half-life of dioxin in the human body is much longer than in the environment, she explained, so dioxin was exerting its effects over many generations of Vietnamese people.
While Marciel said the US would not recognize its responsibility for such health issues, he also said his government continued to "stress that the discussion of the effects of Agent Orange needs to be based on credible scientific research that meets international standards."
But credible research has already prompted the US government's own Department of Veterans' Affairs to officially recognize 11 medical conditions linked to Agent Orange in soldiers who were exposed.
Under President Richard Nixon, the Department of Defense commissioned toxicological studies that found Agent Orange ingredients could be linked to birth defects in laboratory rats, according to the New York Times. The research led to the halt of a decade of Agent Orange use.
The International Agency for Research on Cancer (IARC) at the World Health Organization (WHO) has recognized dioxin as a known human carcinogen since 1997.
In 1988, a study commissioned by the American Legion found a strong correlation between exposure to Agent Orange and benign tumors and skin diseases, according to Robert D. Schulzinger's book A Time for Peace, which explores the lingering effects of the Vietnam War. The research, conducted by Columbia University professors Dr. Jeanne and Dr. Steven Stellman, confirmed a higher rate of miscarriages stillbirths, and birth defects among the female partners of men exposed to Agent Orange.
In a declassified study on the connection between adverse health effects and exposure to Agent Orange, Admiral E.R. Zumwalt Jr. reported to the Department of Veterans Affairs in 1990 on evidence linking Agent Orange to a host of medical conditions. Ironically, it was Admiral Zumwalt who had first ordered the use of Agent Orange in Vietnam.
The document, known as the Zumwalt Report, detailed the health studies that lead to the cancellation of the Agent Orange program.
By October, 1969, the National Institute of Health confirmed that 2,4,5-T could cause malformations and stillbirths in mice, thereby prompting the Department of Defense to announce a partial curtailment of its Agent Orange spraying, said the report.
By April, 1970, the public outcry and mounting scientific evidence caused the US Surgeon General to issue a warning that the use of 2,4,5-T might be hazardous to "our health," according to Zumwalt.
The Secretaries of Agriculture, Health Education and Welfare, and the Interior, "stirred by the publication of studies that indicated 2,4,5-T was a teratogen (i.e. caused birth defects)," then jointly suspended Agent Orange use around "lakes, ponds, ditch banks, recreation areas and crops intended for human consumption," said the report.
Zumwalt also sited several Vietnam-based studies published in the scientific journal Chemosphere that "confirm the incidence of increased birth defects among civilian populations exposed to Agent Orange."
As Agent Orange concerns grew, numerous independent studies were conducted between 1974 and 1983 to determine if a link existed between certain cancerous diseases and Agent Orange, according to the report.
"These studies suggested just such a link," Zumwlat said.
Zumwalt continued: "In 1987, after first being leaked by the New York Times, a VA (US Department of Veteran's Affairs) mortality study was released indicating a 110 percent higher rate of non-Hodgkin's lymphoma in Marines who served in heavily sprayed areas as compared with those who served in areas that were not sprayed. The study also found a 58 percent higher rate of lung cancer among the same comparative groups. Also in 1987, a second VA study found a suggestive eight-fold increase in soft tissue sarcoma among veterans most likely to have been exposed to Agent Orange."
Zumwalt's summary showed that there had never been a dispute over the ill-effects of dioxin among scientists.
"As early as 1983, for instance, the CDC stated in the protocol of its proposed Agent Orange Studies 'that the herbicide contaminant TCDD is considered to be one of the most toxic components known,'" wrote Zumwalt.
Citing reports from scientific studies and research conducted in the US, Western Europe and Russia since the 1940s, the Zumwalt Report demonstrated that testing by chemical companies, governments and outside agencies had concluded that dioxin was dangerous for humans on many levels, whether it was found in Agent Orange in Vietnam, or at paper plants in New Hampshire.
The report concluded: "It cannot be seriously disputed that any large population exposed to chemical agents, such as Vietnam Veterans exposed to Agent Orange, is likely to find among its members a number who will develop malignancies and other mutagenic effects as a result of being exposed to harmful agents."