Since my last blog post on Agent Blue, I have done some more digging and have come up with some interesting findings. To reintroduce Agent Blue, Agent Blue was one of the 6 “rainbow herbicides” used during the Vietnam War. Of these 6 herbicides, the most widely publicized chemical compound remains Agent Orange due to the presence of mutagenic and carcinogenic dioxins. However, Agent Blue also poses a significant health risk due to the presence of sodium cacodylate and cacodylic acid which contain arsenic, one of the top compounds on the United States Environmental Protection Agency (EPA) list of cancer-causing compounds. Agent Blue was used in the destruction of rice by desiccation of the green vegetation, making the crop unable to maintain normal photosynthetic activity and therefore desiccating the crop and making it susceptible to destruction by burning.
As per a research article written by Dr. Kenneth R. Olson, a University of Illinois Urbana Champaign emeritus professor, the driving force behind the use of Agent Blue seems to be in driving out the Vietcong (North Vietnamese militant insurgents) entering South Vietnam through the Ho Chi Minh Trail. Owing to the American bombing operations on the Ho Chi Minh Trail to prevent the VietCong from entering South Vietnam, traversing the Ho Chi Minh Trail was a significant challenge. Owing to this challenge, communist insurgents were unable to carry sufficient food supplies to South Vietnam and proceeded to threaten South Vietnamese Hill Tribes (Montagnards) for rice supplies. The Montagnards, who majorly inhabited the Central Highlands of South Vietnam, which is north of Saigon, and the Mekong Delta, which is South of Saigon, were traditionally food poor and relied on the cultivation of rice for survival. Hence, the “resource denial” program of the US military with the use of Agent Blue aimed to cut off the food supply to approximately 260,000 Vietcong insurgents in South Vietnam, however, this also required the military to cut off food supplied to approximately 17.2 million Vietnamese. In denying a total of 17.5 million Vietnamese these rice supplies, the US military not only made use of Agent Blue but also proceeded to burn the rice crops after spraying the fields with the compound. According to the same research paper, the burning of the paddy fields was done to prevent the Montagnards from procuring the rice grains and replanting the paddy fields.
After the usage of Agent Blue in Vietnam, the excess chemical was sent back to Johnston Island in the Pacific Ocean along with the other herbicides for eventual incineration at sea. However, due to the high concentrations of arsenic in the chemical, it was deemed not fit for incineration since this would pose health risks as the arsenic would be aerosolized. Hence, Agent Blue was instead used to clear weeds at the Davis-Monthan Air Force in Arizona. However, the air force base does not have large civilian populations nearby and hence is assumed not to have posed a significant health risk.
In planning the “resource denial” program, the United States and the Republic of Vietnam hoped that the rural population wherein Agent Blue was sprayed would immigrate to the “strategic hamlets” or urban slums in Saigon, however, only about 1.5 million Vietnamese moved to these slums. The remaining population remained in the Central Highlands and the Mekong Delta, however, there is a lack of data regarding the impact of the lack of food supplies on this population. However, one can imagine the death and destruction that may have resulted from the major staple food of a food-deprived environment being cut off. The counter-productive nature of this US military strategy may be considered as the minimal rice supplies that may have remained for the villagers would have been taken by the VietCong by force, which would ultimately just lead to the starvation of the Montagnards. This has been further supported by Alain C. Enthoven, assistant secretary of defense (DOD) for systems analysis, who has reviewed the RAND report, which strongly opposed the use of herbicides, and concluded that “the existing wholesale food crop destruction program was counterproductive because it alienated the affected of the South Vietnamese population without denying food to the communist insurgents.” Although this is one explanation for the inefficacy of the “resource denial” program, an alternative explanation provided by the RAND Corporation in 1967 was that spraying the rice paddies to starve the enemy would be nearly useless because there is enough rice in Vietnam to feed everyone, even after destroying approximately 13.7 million hectares of rice paddies.
Although the immediate impact of the use of Agent Blue may have been the destruction of millions of hectares of rice paddy, the chemical compound continues to affect the Vietnamese even today. In the same research paper written by Dr. Olson, it is stated that the arsenic introduced through Agent Blue remains in the saturated soil environment through the following processes: “1) reacting with and being retained by the compounds in the soil, 2) volatilized into the atmosphere from biological transformations and burning, 3) leached out through the saturated soil into groundwater, and 4) taken up by plants from groundwater and accumulated on the topsoil.” “Arsenic exposure and the Induction of Human Cancers” by Martinez et al. has found that the more severe effects of arsenic contamination of drinking water, such as cancer, are evident up to several decades after exposure has ceased. Furthermore, a case study of a 67-year-old Caucasian Vietnam war veteran found skin cancer in the patient with no other source of arsenic exposure or hereditary links to skin cancer. This led the researchers to conclude that prolonged exposure to Agent Blue due to drinking well water or prolonged exposure to paddy fields where Agent Blue was sprayed may lead to the development of skin cancer. The impact of bioaccumulation of arsenic is also of great concern since the arsenic in the groundwater may bioaccumulate in the fish, shrimp, and birds, and then further bioaccumulate in the Vietnamese people when eaten. Dr. Olson, in drawing a comparison between Agent Orange and Agent Blue, has said that although dioxin in Agent Orange has a half-life, arsenic does not, and hence poses an additional risk of bioaccumulation and its consequent health risks.
While talking with Dr. Olson, he highlighted the need for intervention considering that the arsenic is being cycled in a manner that allows it to permanently remain in the water in the region. Furthermore, an authoritative study was done by the National Academy of Science on the Rainbow Herbicides and their use in South Vietnam had little scientific information about the soil-chemical processes of arsenic. The study assumed that because arsenic was naturally occurring in the soil, it was not harmful to humans or animals. Other studies, such as “Arsenic exposure to drinking water in the Mekong Delta” by Merola et al. have found elevated levels of arsenic in the groundwater used for drinking in the Mekong Delta, Vietnam. Dr. Olson hence suggested that, at this time, the extent of the impact of the arsenic added to the soil through Agent Blue is uncertain, however, adding millions of kilograms of arsenic to the soil and water could not have helped.
In the United States, Agent Blue resulted in the contamination of the Menominee River, Michigan with arsenic. Agent Blue was entirely produced by the Ansul Company at a chemical plant in Marinette, Wisconsin. Improper waste disposal by the company led to the contamination of the Menominee River with arsenic. Although the company undertook multiple decontamination efforts under two consent orders from the Wisconsin Department of Natural Resources and the U.S. Environmental Protection Agency in September 2009, the Menominee River remained contaminated with arsenic from the start of production of Agent Blue in 1961 up to the cessation of decontamination efforts.