In 1961, U.S. President J. F. Kennedy approved a counter insurgency strategy for South Vietnam (Figure 14) and the U.S. Department of Defense and perhaps the CIA initiated a program to investigate herbicide use as a defensive weapon in guerrilla warfare [1]. Ambushes, sabotage, fast-moving small-scale raids and other guerrilla warfare tactics were used extensively by the Democratic Republic of Vietnam in their war against U.S. troops in South Vietnam. These hit-and-run tactics, dependent upon the element of surprise, were largely successful because the dense tropical vegetation hid military personnel, armed civilians, supply lines, and an extensive network of covert soil tunnels (Figure 15) [15].

The first shipment of herbicides to be used tactically arrived in South Vietnam on January 9, 1962 at Tan Son Nhut Air Base in 208-liter drums. The herbicides including Agent Orange were sprayed from low-flying C-123 Fairchild Provider aircraft (Figure 16) powered by either turbojets or propeller engines. Helicopters were refitted with 3800 liter chemical tanks, sprayers, and MC-1 Hourglass pump systems [16]. To maximize the contact of herbicide (Figure 17) with the forest and to minimize drift, the spray sorties were restricted to calm days and only sprayed early in the morning. Trucks, Navy boats and backpack sprayers were also used to spray herbicides.

The U.S. Vietnam herbicide campaign was called Operation Ranch Hand and was carried out by a close-knit group of pilots who aerial sprayed about 95% of the herbicide [16] [17]. From January 1962 (3 years before the official esculation of the American-Vietnam War) to January 1971, Operation Ranch Hand flew more than 19,000 combat sorties with jungle defoliation and crop destruction

missions [18]. The amount of Agent Orange and other herbicides sprayed during each mission has been variously estimated at 105 - 119 kg [19] and 221 to 336 kg [20]. An unknown fraction of aerial spraying by the U.S. Navy was over river transportation corridors and coastal regions. Herbicides contaminated with dioxin TCDD could enter waterways and sediments via bank spraying as well as surface runoff and soil erosion from the sprayed areas [19].

U.S. Air Force records officially document 6542 spraying missions (Figure 17) covered 12% of the total area of South Vietnam by 1971. Between 1962 and 1971, more than 20% of southern Vietnam forests were sprayed one or more times [19] and approximately 10 million ha of agricultural land was sprayed (Figure 18) The defoliation campaign destroyed 20,000 km² upland forests and mangroves and thousands of km² of crops. Herbicides were applied at 13 to 20 times the recommended USDA rate. As a result the dioxin TCDD concentrations in the soil and water were hundreds of times above the levels considered safe by the newly created (1970) USEPA.

Vast areas of South Vietnam were stripped bare of vegetation (Figure 19) including U.S. military bases perimeter fences in Vietnam after receiving high concentrations of the dioxin contaminated Agent Orange and arsenic-based Agent Blue herbicides. The Ho Chi Minh Trail in Laos and Cambodia (Figure 20) also received high concentrations of dioxin TCDD and arsenic (via U.S. Air Force bases in Thailand). One of the most contaminated sites was the Cu Chi soil tunnels region (Figure 21) and agricultural and horticultural areas [15] located 40 km to the northwest of Ho Chi Minh City (formerly Saigon). Today, tourists can view and crawl through a portion of these Cu Chi soil tunnels

network. The Vietnam Memorial Park shows a 40-year old black and white film of Vietnamese women picking fruit near Cu Chi in what was once known as the Garden [15]. A variety of trees, jungle undergrowth) (Figure 22), and bamboo have grown up in the bomb craters of Cu Chi during the last 45 years and rubber tree plantations (Figure 23) have been recently been established.

The targeting of food crops began in October of 1962, but the U.S. public was not made aware of this DOD and USDA action until 1964. More than 40% of all herbicide spraying targeted the destruction of food crops (the original military objective). Members of the U.S. Congress were told in 1965 that crop destruction was the most important purpose of the herbicide campaign, but media reports focused only on jungle defoliation in support of ground combat. Post-war analyses show that nearly all of the destroyed food crops were grown for the rural civilian population and not for the guerrillas. Crop destruction left hundreds of thousands of Vietnamese people malnourished or starving and contributed to widespread famine in rural southern Vietnam and movement of the Vietnamese population (at least 2 million) to the slums of Saigon and other cities.

U.S. planes and helicopters sprayed Agent Orange and other herbicides over the Ho Chi Minh Trail jungle canopy to expose and bomb enemy forces and their supply bases. After the 1968 Tet Offensive, the Cu Chi and Iron Triangle agricultural and forested areas were defoliated and used as a free strike zone [19]. The demilitarized zone at the 17^th Parallel was frequently sprayed to eliminate vegetation. As a result, “thousands of acres of jungle were transformed into the tropical equivalent of a winter forest” [20].

Other targets for defoliation were low-lying wetlands at the interface of uplands, rivers and canals. The extensive U Minh mangrove forest in Ca Mau Peninsula, headquarters for communist resistance fighters, and other remote locations known to house opposing troops were also defoliation targets. Herbicides were heavily sprayed on both sides of perimeter fences of U.S. military bases in

southern Vietnam to ensure visibility and alert military base security of pending raids and sabotage. U.S. military personnel were unintentionally exposed to highly concentrated mixtures of herbicides with dioxin TCDD [21]. A third target, rice and other food crops were sprayed primarily with Agent Blue shortly before the rice matured. Agent Blue, the arsenic-based herbicide, was intended to kill or eliminate the food supply for the soldiers, coming down the Ho Chi Minh Trail, and fighting in southern Vietnam. This led to high levels of food insecurity in the rural civilian population.

In 1957, scientists at Fort Detrick (formerly Camp Detrick) started to test the activity of cacodylic acid (Figure 24) used in Agent Blue on rice. Cacodylic acid in mixtures with 2,4-D and 2,4,5-T was tested in Maryland (1956), Dugway, Utah (1959) and Fort Drum, New York (1960) [21].

The first tactical herbicide barrels started arriving in Vietnam in 1961. Herbicide Blue liquid (later called Agent Blue) was a yellowish-tan liquid that was insoluble in diesel fuel but soluble in water [21]. One gallon (3.9 liters) of Agent Blue contained 1.4 kg of the active ingredient cacodylic acid. Agent Blue contained both cacodylic acid as a free acid and sodium salt cacodylate. The active ingredients were 65% cacodylic acid and 70% of salt sodium cacodylate. Agent Blue (C₂H₇AsO₂) was first used in southern Vietnam on the north side of Route 15, northwest of Saigon on 12 January 1962. In addition to Ranch Hand aircraft, the Vietnam Air Force (VNAF) used several H-34 helicopters, and one C-47 aircraft to evaluate applications of the herbicides [21]. These flight records were not recorded and if recorded were not maintained. It appears the spraying was not done as part of Operation Ranch Hand or it would have been recorded and the records would have been maintained. Some tests were conducted on the Ca Mau Peninsula [22]. Rubber vats or fuel bladders filled with Agent Blue were

apparently dropped from helicopters on the rice paddies to increase the rice-killing efficacy.

In 1961, the Kennedy administration approved the use of the tactical herbicides (1961-1971) program, which led to formal use of herbicides including Agent Blue during the Vietnam War. Herbicides had two primary military objectives: 1) to destroy the food crops available to the enemy, and 2) defoliate trees and plants to improve military observation of enemy activity. The program was initially used against both the South Vietnamese civilians and the National Front for the Liberation of Southern Vietnam (NLF).

The effects of defoliation were studied by comparing soil properties (Figure 25) in defoliated and non-defoliated mangrove areas northeast of Nam-Can (Ca-Mau Peninsula). The only positive effect was that mangrove area spraying made the areas safer from the NLF by denying cover from within and was easier to clear land for irrigated fields. However, woodcutters recognized that their primary wood resource was being eliminated [21].

Within the 10 years, the land impacted or damaged by Agent Blue, primarily rice paddies, totaled nearly 400,000 ha in South Vietnam, mostly near Da Nang and Saigon with over 51,000 ha of forest defoliated at least 4 times. Approximately, 27,000 ha of mangroves, mostly along the South China Sea, were completely destroyed, as were 300,000 ha of rice paddies in the Mekong Delta and Central Highlands [20]. The official Operation Ranch Hand records and flight maps show little activity in the Mekong Delta, the primary rice growing region. Why? Perhaps the official records are incomplete. The removal of the local food supply for the enemy was the primary military objective between 1962 and 1965 (before the esaclation of the American-Vietnam War) and not defoliation of the jungle vegetation. There is evidence that 2 million people from the Mekong Delta moved to the slums of Saigon and other cities. Why did Vietnamese leave the Mekong Delta and their food rich (rice and fish) sources? The main driver was the political policy of Republic of Vietnam (RVN) to relocate the people into “strategic hamlets” which the government (Diem) felt were easier to defend, than a few families scattered in small villages, from the influence of the insurgents.

After President Nixon signed the Paris Peace Accords on January 27, 1973, the herbicide known as “Agent Orange” still remained in the Kelly Air Force base (Figure 30) chemical stockpile [29]. DOD transferred the Agent Orange to the USDA, Forest Service for brush and broad leaf weed control. This Kelly Air Force base chemical stockpile was likely one of the primary sources of Agent Orange used by the USDA, Forest Service and partners in the Western United States in the 1970s to control the brush and broadleaf weeds after clear-cutting. This was the subject of a 2021 PBS documentary Independent Lens on “People vs. Agent Orange” [30] and a 2021 Vietnam Veteran News podcast 2086 by Mack Payne [31]. The DOD transfer of Agent Orange to the USDA, Forest Service would not have been an issue since Agent Orange (a 50:50 mixture of 2,4-D and 2,4,5-T) components created was formulated for dual military and agricultural uses. The excess, Vietnam War Agent Orange and components, stored at Kelly Air Force base, San Antonio, Texas, were transferred by DOD to the USDA, Forest Service for use in the Western United States forests. As stated in the 1959 Armed Services Procurement Act and subsequent Department of Defense directives make the use of coordinated Federal and Military mandatory for the procurement of items, materials and service, meaning all materials could be used at any Federal installation. Agent Orange “Federal Specifications” were formulated and approved by Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) for use by the U.S. military or any federal agency. The USDA, Forest Service and timber and chemical company partners in the Western United States to prevent shrub and broadleaf weed regrowth competition with planted trees on clear-cut public forest lands using these same chemicals used before, during, and after the Vietnam War.

The USEPA Region 10 reported on the Federal Use of Pesticides, for the years 1984 and 1985, by 17 federal agencies in Idaho, Oregon and Washington (but not for Alaska) [32]. Fifteen of the federal agencies provided the requested information. Only the USDA, Agricultural Research Service (ARS) and the Justice Department (DOJ), Drug Enforcement Administration (DEA) failed to submit reports. The DEA failed to respond to requests to provide pesticide use data for national security reasons. It appears USDA, ARS uncooperative response to the request for EPA’s pesticide use/disposal information fostered suspicions that the ARS must be using pesticides in a manner which would have been disapproved by the EPA. National and regional level federal agency staffs were especially sensitive about providing pesticide disposal information. Many Agency staffs either did not have a good understanding of what happened at the application/disposal level or did not wish to provide disposal information. The typical responses were: 1) certified, private contractors were responsible for disposal activities, 2) pesticide containers are disposed of as directed on the pesticide container label, and 3) no excess pesticides existed. Or the pesticides were all used up. Many agencies reported the use of large quantities of pesticides, which were water soluble and a potential risk to groundwater as contaminants, to the EPA’s Office of Pesticide Programs [32].

Federal agency pesticide record keeping systems varied greatly. Some agencies tracked pesticides when used while other agencies record systems consisted of filing and storing pesticide use proposals submitted by field offices. Once approved the field offices can apply for any quantity up to the maximum amount listed on its proposal. Some agencies had up-to-date data while others had data which had not been updated for several years. Record keeping was by month, fiscal year, or calendar year. Pesticide quantities, target species, and/or application locations were not always provided or were provided with varying degrees of precision [32].

The herbicide 2,4,5-T was banned in 1985, the year these survey reports were requested by USEPA Region 10. The EPA requested records for 1984 and 1985. The critical data for the early 1970s were not included in the EPA request for information. In the early 1970s the DOD transferred USDA Agent Orange, 2,4,5-T and perhaps Agent Blue, the arsenic based herbicide, from the Kelly Air Force base chemical stockpile that was left over from the Vietnam War or had remained in the supply chain. The Department of Navy had quantities of 2,4,5-T and DDT which could have been commercially purchased. However, the Bureau of Indian Affairs (Warm Springs Agency-Oregon) still had 14 gallons of a mixture of 2,4-D and 2,4,5-T left over after previous spraying. This mixture was not commercially available for federal agencies to purchase. Therefore, it had to have been mixed by agency staff or it was residual Agent Orange herbicide from the 1970s DOD transfer of the Kelly Air Force base transfer to the USDA and then to the Bureau of Indian Affairs. If the Agent Orange and/or 2,4,5-T herbicides were transferred from the DOD to the USDA to the Bureau of Indian Affairs in the early 1970s there should be records [32].

The USDA, Forest Service manages 18 million hectares in Idaho, Oregon and Washington which did not include Alaska which is also in USEPA Region 10. Nor does it include forest lands in other Western USEPA regions. The pesticide data was only for FY 1984 and 1985 and did not include previous 1970s data. Due to a Federal Court injunction Federal agencies were prevented from spraying pesticides in Oregon in 1984 and 1985 (most likely as a result of Agent Orange vs. People legal action) [13]. The Bureau of Land Management (BLM) pesticide use, in its 1984 and 1985 noxious weed control program, was reduced dramatically from 1983 pesticide spraying levels. The real reason for the reduction was a federal court injunction issued on Dec. 2, 1984 which prohibited BLM and other federal agencies from spraying pesticides in Oregon. After that date BLM was required to prepare a “worst case analysis” before it could resume pesticide spraying.

What was the fate of Agent Blue, the arsenic based herbicide, stored at Kelly Air Force base after the end of the American Vietnam War? GAO records also show that approximately 173,910 gallons of the herbicide Agent Blue [13] containing the active ingredient cacodylic acid (with arsenic) (Figure 24), in addition to the Agent Orange and components, was stored at Kelly Air Force base. It is not clear how this massive amount of arsenic-rich Agent Blue was utilized or disposed of after President Nixon signed the Paris Peace Accords, ending direct U.S. involvement in the Vietnam War, on January 27, 1973. Agent Blue, with its active ingredient cacodylic acid, was a dual purpose herbicide developed during WWII, could also have been transferred to USDA, Forest Service, for weed and grass control in clear cut in Western United States forests. If the USDA, Forest Service and their partners applied Agent Blue, arsenic, which does not have a half-life, arsenic would have remained in the Western United States forest soils [13]. At this time, how and where the herbicide, Agent Blue with the active ingredient cacodylic acid (As), was utilized or disposed of is not clear. Was it transferred, along with Agent Orange, by the DOD from Kelly Air Force base chemical stockpile to USDA, Forest Service after the end of the Vietnam War? The USDA, Forest Service goal was to control grass, weeds and brush in recently clear-cut and re-planted Western United States forests. Agent Blue was known to be effective in the eradication of grass and narrow leaf weeds [21]. If Agent Blue was not used on Federal lands in Western United States, then what happened to the 173,910 gallons of Agent Blue that were stored at Kelly Air Force base after the herbicide was no longer needed in southern Vietnam? Perhaps the herbicide was applied to the Western United States forest. Was the herbicide applied to the Western United States forest?

The Menominee River flows into Lake Michigan via Green Bay (Figure 37). The Ansul Chemical Company at Marinette, Wisconsin (Figure 38) and (Figure 39) manufactured the Agent Blue, an arsenic containing herbicide, used in the Vietnam War during the 1960s and 1970s. The Agent Blue was shipped via Green Bay and the Great Lakes (Figure 40) and the St. Lawrence Seaway to the Atlantic Ocean. Almost all (98%) of the Agent Blue used in the Vietnam War from 1961 to 1971 was manufactured at Ansul Chemical plants on the Menominee River in Michigan and Wisconsin [21]. The contaminated surface water and sediments near Ansul manufacturing plant flow into the Menominee River. The groundwater and the river bottom sediments are heavily contaminated with arsenic, which was released by Ansul Company from 1957 to 1977 resulting from the manufacture of Agent Blue. Ocean going ships then passed through the Panama Canal (Figure 41) and the Pacific Ocean on the way to the South China Sea.

Fewer 208-liter barrels of Agent Blue with a blue stripe were sent, via ocean going ships through the Panama Canal [13], to South Vietnam than Agent Orange barrels with an orange stripe. Between 1962 and 1971, the U.S. used an estimated 7.8 million liters of Agent Blue herbicide (1,132,400 kg of arsenic) applied as a chemical weapon for “crop destruction and defoliation”. Agent Blue was applied primarily on the mangroves, rice paddies [42], and the surrounding forest of South Vietnam. Agent Blue was eventually also used in Laos along the Ho Chi Minh trail (Figure 20) to kill crops and upland rice in the Central Highlands in order to deprive the North Vietnamese communist insurgent troops a food source (Figure 42). The Agent Blue was applied at the average rate of 2.83 kg As/ha for the total rice paddy and forest area (Figure 43). Many areas were

sprayed only once while other areas received four or more applications. The forest and mangrove areas were usually sprayed (Figure 43) at a different rate than the rice paddies. Unable to control the guerrillas access to their food supplies or eliminate their grassroots village support, the U.S. military response was simple: “If you cannot control it, kill it” [28] [42].

Agent Blue destroyed food crops (rice) by desiccation of the green vegetation making the crop unable to maintain normal photosynthetic activity thereby desiccating the crop and making it susceptible to destruction by burning. The application of arsenic based herbicide was required to overcome the incredible resistance of rice to conventional methods of burning. Herbicides destroyed the food crop fields in 2 - 4 days and left the soil unsuitable (Figure 44) for further planting within a month. In this way, the Republic of Vietnam and United States militaries ultimately destroyed at least 300,000 ha of food crops (rice) [28] [43].

Agent Blue, a “tactical herbicide” used by the United States military during the Vietnam War, was inspired by the British use of herbicides and defoliants applied during the Malayan Emergency (1950s) to provide a precedent for its use. Destroying rice to prevent its consumption by the enemy was a U.S. and Republic of Vietnam military strategy at the very start of U.S. military involvement in Vietnam War.

Initially, Republic of Vietnam and United States soldiers attempted to blow up dikes and raised borders around rice paddies to dry them up by using mortars and grenades. However, mature rice grains are very durable and not easily destroyed even if the rice plant is deficient of water due to paddy drainage. Every grain of rice that survived became a seed to be collected and re-planted. The U.S. military discovered that rice grain is one of the most difficult plant materials to destroy [21]. However, if an herbicide like Agent Blue was applied by spraying before the rice plants were mature, it could mean a 60% to 90% rice crop loss. If subsequently burned, the immature rice seeds could be destroyed. However, the burning of arsenic treated vegetation resulted in the release of volatile arsenic containing aerosols and ash into the atmosphere. Surviving rice was contaminated, as well, with trace amounts of arsenic. Rice grown in the Vietnam to this day is still tainted by trace amounts of arsenic probably from both anthropic and natural sources.

At the end of 1967 an International War Crimes Tribunal stated that: “The soldiers discovered that rice is one of the most maddeningly difficult substances to destroy; using thermite metal grenades it is almost impossible to make it burn and, even if one succeeds in scattering the rice, this does not stop it being harvested by patient men.” The U.S. and South Vietnamese military went to “bigger and better” options that would actually destroy entire rice paddies [2].

“Ranch Hand”, was the military code name for spraying of herbicides by U.S. military aircraft in Vietnam and Laos from 1962 through 1971 [43]. In this case, the widespread use of Agent Blue by the Republic of Vietnam and United States militaries was an attempt to take away the enemy’s food supply by depriving them of food resources.

Agent Blue was primarily used to desiccate and kill narrow-leaf plants and trees such as bamboo, grass, rice, and bananas. The rice plant is highly dependent on water to survive. Spraying Agent Blue on paddies can destroy approximately 60% of an entire rice paddy and leave it unsuitable for intermediate re-planting. After the war, the Vietnamese people would then harvest and eat the tainted rice, fish, and shrimp for the next 55 years [21].

A study done by Watson et al. [44] found that life expectancies of animals (Figure 45) exposed to Agent Blue were reduced. For rats the lethal concentration of Agent Blue was 3.5 µg/L. Soldiers with prolonged exposure to Agent Blue had a garlic odor in their breath, which is one of the common noticeable symptoms of arsenic poisoning. Research shows the human liver absorbs 40% of the cacodylic acid [23] [45]. The extreme levels of arsenicals and high bioaccumulation of arsenicals in the body are detrimental to crops and human health.

Military personnel applied Agent Blue by using hand sprayers on backpacks, trucks, and riverboats or sprayed from helicopters on rice paddies and adjacent canals. In some cases, Agent Blue was also used to kill bamboo (Figure 46). The military personnel were told that the herbicides including Agent Blue were harmless and the herbicide handlers including Vietnamese soldiers and civilians did not need to wear protective gear such as facemasks, googles, gloves and suits. Agent Blue often contacted the exposed skin of the military personnel (Figure 47) who were spraying [21] [45]. The military personnel involved in Operation Ranch Hand were in three risk categories separated by the level of potential danger to herbicides including Agent Blue. Navigators, co-pilots, and pilots were thought to be at low risk for exposure and contamination [24]. The moderate risk group included the military personnel who loaded or re-drummed the herbicides (Figure 48), the crew chiefs, the mechanics and personnel who repaired the tanks and spray equipment [24]. The high-risk group included the flight engineers who operated the spray equipment. However, often unrecognized herbicide included the crews of fire support and escort aircraft which often had to maneuver around the spray aircraft to suppress ground fire and ended up flying through the spray stream or spray drift without protective gear. The empty

Agent Blue barrels were washed and poured out on the ground by hand often without protective gear and then re-purposed for improvised showers, to store drinking water or even as barbeque pits or sold to locals. The rinse water from cleaning the barrels was poured on the soil surface and either leached into the soil and groundwater [46] or was transported off-site during monsoon rains into the waterways [21].

Agent Blue harmed village food supplies and forced many rural villagers into the “strategic hamlets” or urban slums after destroying hundreds of paddies with arsenic laced Agent Blue. Alain C. Enthoven, assistant secretary of the defense (DOD) for systems analysis, reviewed the RAND report and concluded, “existing wholesale food crop destruction program was counterproductive because it alienated the affected South Vietnamese population without denying food to the communist insurgents.” However, others responsible for U.S. military strategists did not agree [21].

An Act of Congress, Public Law-441, and Fiscal Year 1971 Military Procurement Authorization Act Section 506-9c authorized a NAS study. The Secretary of Defense was required to make arrangements with the NAS to conduct a comprehensive study (Sep. 1971 to Sep. 1973) and investigate physiological and ecological dangers in inherent use of the defoliation program by Department of Defense in South Vietnam [10] (Figure 43) [15]. NAS scientists spent 1500 scientist days working in Vietnam during the Vietnam War and found it impossible to determine whether arsenic found in the rice paddy soils was from the herbicide spraying of Agent Blue, from other sources, or was present naturally in the soil prior to the spraying.

The NAS overflight was conducted on January 27, 1972 of the Song-Re Valley, Quang-Ngai Province. This over flight of an area, which was sprayed with Agent Blue on August 9, 1970, found that rice fields and vegetable plots appeared normal from the low flying aircraft. NAS [10] analyses of a small number of samples of fish, rice, shellfish (Figure 49), worms, soils and water collected near a community in Rung Sat, which was subjected to Agent Blue missions between 1964 and 1969 found the arsenic levels within the normal ranges.

NAS scientists studied the effects of Agent Blue on settlements by interviewing the villagers and reported their findings in a report entitled “Effects of Herbicides on Humans” [10]. Human reactions to military spraying of tactical herbicides were documented [47]. Herbicide spraying including Agent Blue resulted in the displacement of people from their rural homes into government sponsored villages as part of the Diem government’s “strategic hamlet” policy and urbanization movement into the slums of Saigon and other larger cities. Only one of 18 rural areas increased in population during the 1960s. After spraying of tactical (Rainbow) herbicides and subsequent burning of crops, individuals in every community interviewed reported on who became ill or died after the

spraying, or because of eating of herbicide-treated plants or drinking contaminated water. The NAS report [10] (Figure 29) was translated into Vietnamese for the locals to read. Vietnamese had to live with the consequences and had to undertake remedial action. Financial and technical support from the U.S. (funds and training for Vietnamese workers), lent professional technical personnel, and equipment.

Herbicide damage effects included: 1) loss of potential production at the plant stage before growth and grain production became economically valuable, and, 2) loss of commercial products such as grain, timber and fruit and lack of young plants including seedlings and seeds required maintaining food production. The effects of crop damage were revealed primarily from studies of rural settlements and interviews with villagers. The results were reported under the “Effects of Herbicides and Humans.” Human reactions to military spraying of tactical herbicides were included in studies on mangrove forests and Vietnamese and Montagnard rice paddies, coconut plantations, gardening, and upland crop areas [10]. The tactical herbicides were destructive to health and livelihoods of the people whose land was sprayed.

The arsenic-laden Agent Blue herbicide was used to kill rice food crops and bamboo. Spraying Agent Blue added a significant amount of water-soluble arsenic to the rice roots, rice grains, water, and soil. The United States and Republic of Vietnam militaries sprayed and dumped Agent Blue on the rice paddies to desiccate rice plants and then burned the rice residue and seeds. As a result, toxic As-containing aerosols and smoke were released to the atmosphere.

The goal was to clear out crops and foliage to improve military intelligence, achieve enhanced security, increase availability of troops used for combat, reduce cover for enemy resistance, and reduce United States personnel casualties [3]. Between the first test in Kontum base in southern Vietnam on August 10, 1961 and the last spraying in October 1971, tactical herbicides including Agent Blue were shipped to and sprayed all over South Vietnam. U.S. and Vietnam public ongoing concerns: did the extensive use of tactical herbicides including Agent Blue modify the environment of Vietnam beyond the point of recovery? Agent Blue did not raise the arsenic levels in the groundwater above the 1970s drinking water standards [10].

There were many spikes in the arsenic levels (above WHO standard) in the Mekong Delta groundwater. Arsenic was bio-accumulated in the Vietnamese because of elevated arsenic levels in the drinking water and food supply. Medical evidence collected from U.S. veterans and Vietnamese and their offspring during the next 50 years suggests there was significant genetic damage [45] [47]. Documented effects of herbicide damage were: 1) the loss of potential food crop production at a stage before maturity and crop becomes economically valuable, and 2) the loss of commercial products such as grain, timber, fruit, seedlings and seeds required maintaining food production.

Subsequent industrial development and wastewater treatment plants have contributed to dangerous bio-available arsenicals in the surface and groundwater of the Mekong Delta. During the last two decades, thousands of government- subsidized shallow tube wells have been built. Shallow groundwater has become the major source of arsenic rich water for irrigation and drinking in Vietnam. Groundwater arsenic in concentrations has measured as high as 3050 ug/L. The Vietnam War’s “Operation Ranch Hand” contributed to the crisis of arsenic contamination in South Vietnam upland and lowland rice paddies (Figure 50). However, the NAS [10] findings suggest arsenic levels were still below WHO standards. Fortunately, southern Vietnam farmers had not yet started pumping the groundwater to the surface for rice paddies or shrimp ponds.

NAS [10] studied the effects of defoliation by comparing soil properties (Figure 25) in defoliated and non-defoliated mangrove areas northeast of Nam-Can (Ca-Mau Peninsula). The only positive impacts recognized came from the spraying of the mangrove area (Figure 18), which increased security from the NLF because it was easier to clear land for irrigated fields. However, woodcutters recognized that their primary resource was being eliminated.

In 2009, the Ansul Company operated under two consent orders for environmental mitigation; one from the Wisconsin Department of Natural Resources and another from the U.S. Environmental Protection Agency (EPA) [21]. In

September of 2009, Ansul Company agreed to spend an estimated $28 million on:

1) Removal 56,600 m³ of arsenic-contaminated sediments from the Menominee River;

2) Construction of an impermeable barrier to bedrock for about 160,000 m² of sediment;

3) Cap or remove 17,000 m² of surface soils contaminated with arsenic levels above 16 - 32 ppm;

4) To pump and treat contaminated groundwater;

5) The total remediation costs were: 1976-1984, $11 million to pump and treat contaminated groundwater at the southern property border and to install a groundwater interceptor trench [21] in 1998-1999, $12.4 million to remove arsenic-contaminated sediment from the 8^th Street section of the Menominee River and

6) An impermeable barrier system was installed to bedrock near the 8^th Street slip and adjacent salt vault.

In 2012-2013, approximately $25 million was spent to dredge and then cap contaminated river sediments due to an EPA order of the removal of 190,000 m³ of sediment from the main channel. The project cleanup began in July of 2012 after Ansul (Tyco) Company hired Stevenson Environmental Services of New York as the general contractor.

A recently released report of the United States Government Accountability Office (GAO) focused on the actions needed to improve the accuracy and communication of information regarding storage and testing locations of Agent Orange outside of Vietnam including Kelly Air Force Base in Texas [25]. The GAO report confirmed that the Military Sea Transportation Service directly chartered merchant vessels to carry tactical herbicides through the Panama Canal during the Vietnam War. These tactical herbicides, including Agents Blue and Orange, were stored vertically on pallets in internal storage compartments on the vessels. There is no official evidence to show the tactical herbicides were ever offloaded in Panama Canal Zone [48]. However, there are other documents [49] [50] [51], that support the presence of similar formulated commercial herbicides 2,4-D and 2,4,5-T containing unknown amounts of dioxin TCDD. A December 1976 Environmental Sampling Report for the Panama Canal Zone showed chlorophenoxy herbicides were detected in the soil samples from the Canal Zone [52]. Chlorophenoxy herbicides are identified by the Centers for Disease Control and Prevention as 2,4,5-T based herbicide containing unknown amounts of dioxin TCDD [52]. In the 14th Annual Meeting of U.S. Army Corps of Engineering report on the “Aquatic Plant Control Research Program” a section notes the June 1978 initiation of large-scale testing of 2,4-D on water hyacinth [53]. However, not all of the test site locations have been provided. Since commercially available 2,4-D was used on military bases in Panama Canal Zone this herbicide would have been available for use on the hyacinth problem in Lake Gatun; however, no official records have been found that the Lake Gatun was used as a test site [18] [29] [54]. Was Lake Gatun used to test 2,4-D on hyacinths? If so were the findings of the “Aquatic Plant Control Research Program” published? If Lake Gatun was not used as a test site, why not?

Herbicides with 2,4,5-T with dioxin TCDD contaminant were shipped through the Panama Canal Zone. The U.S. Government and Military have for more than 60 years asserted those tactical herbicides such as Agent Orange and Agent Blue were neither off loaded in the Panama Canal Zone [47] nor aerially sprayed on the Tropical Forests of the Panama Canal Zone” [18]. Many Panama Vietnam Era Veterans have claimed that they handled and/or were exposed to toxic chemical sprays [49] [55] [56] have over the years challenged this official military statement [49]. Panama veterans who claimed to have been exposed to commercial herbicides including 2,4,5-T containing unknown amounts of dioxin TCDD, have filed for VA benefits but have been repeatedly denied benefits [51] since the tactical herbicides were not officially offloaded and/or applied to the Panama Canal Zone landscape [49]. However, commercial herbicides containing 2,4,5-T with an unknown amount of dioxin TCDD were used on the U.S. military base grounds [57] [58].

These commercial herbicides were very similar (composition and strength) but often have lower dioxin TCDD contents [59] [60] than the restricted use tactical herbicides being transported through the Panama Canal Zone to the South China Sea for use during the Vietnam War. The U.S. Government and Military declared, on the official record [48], that tactical herbicides were never used in the Panama Canal Zone [49] [50]. However, DOD was not really claiming that “unrestricted commercial herbicides” were never requisitioned, offloaded, handled, and applied by military personnel to the military base grounds and perimeter fences [55] [56] [57] at the direction of the Base Civil Engineer Commanders. It is also assumed that any aerial spraying done by aircraft only involved commercially available herbicides including 2,4-D and 2,4,5-T containing unknown amounts of dioxin TCDD [13]. However, three C-123 (Figure 16) aircraft that were used to spray Malathion in the Panama Canal Zone may have been previously contaminated with tactical herbicides, containing dioxin TCDD and arsenic, in other theaters of operation including South Vietnam. After DOD announced that the use of Agent Orange was suspended in on April 15, 1970 the military started to ship C-123 aircraft back to U.S. territories [13].

In 1970, three C-123 aircraft previously used to spray tactical herbicides in Vietnam [13] and contaminated with tactical herbicides (including Agent Orange and Agent Blue) residues (dioxin TCDD and arsenic) in their spray tanks, were relocated via a transport ship in 1970 to Howard Air Force base in Panama. These TCDD and arsenic contaminated C-123 airplanes (Figure 16) were used from 1970 to 1973 to spray Malathion in the Panama Canal Zone [13]. This may have resulted in trace amounts of tactical herbicide Agent Orange (dioxin TCDD) and Agent Blue (arsenic) [21] being added to the soils and water of the Panama Canal Zone.

The herbicides 2,4-D and 2,4,5-T containing low levels of TCDD were commercially available and thus could be ordered and used separately by any Federal Agency (including the military and USDA) and shipped to and used on the Panama Canal Zone military base grounds [56] [57]. While there are no official documents which prove tactical herbicides, such as pre-mixed Agent Orange, were ever off-loaded in Panama Canal Zone [49] and/or sprayed on the tropical forests and islands in the Panama Canal Zone. There are commercial ship transport records which show commercial herbicides, Orange, Ester-Butyl, 2,4-D and 2,4,5-T containing the contaminant TCDD were used on military bases in the Panama Canal Zone [55] [56]. Even if tactical herbicides were never off-loaded and sprayed in the Panama Canal Zone, the commercial herbicides including 2,4,5-T by-product containing unknown levels of TCDD were used on the military base grounds and perimeter fences by military base personal to control the vegetation and insect pests and would have added TCDD to the Panama Canal Zone environment. There is evidence that DDT and Malathion (first registered in 1956) [13], 2,4-D and 2,4,5-T with the contaminant dioxin TCDD were sprayed on Panama Canal Zone highways, structures, military grounds, and perimeter fences using sprayers mounted on trucks in the Panama Canal Zone.

The extent of the current chemical and pesticide contamination on former Panama Canal Zone U.S. military base grounds and in Lake Gatun and the Panama Canal channel (Figure 51) is unknown [13]. Systematic soil sampling of former military bases, chemical disposal sites, and sediment sampling of the Lake Gatun or the Panama Canal sediments is needed to determine if mitigation is still required.

Historically, most of the world’s chemical weapons were disposed of at sea. This included the arsenic-based chemical weapons [16]. These chemical weapon disposal sites were not well documented. Once dumped into the sea, the chemicals leaked because of the corrosive action of seawater on steel barrels and containers. Davis-Monthan Air Force Base, near Tucson, Arizona is the home of the U.S. aircraft boneyard where retired military aircraft are stored (Figure 52). After DOD stopped the spraying the tactical herbicides including Agent Blue the excess stocks were removed from Vietnam by 1972 [18]. Most of these tactical herbicides, used during the Vietnam War and containing dioxin (TCDD) herbicides, were transported to Johnston Island in the Pacific Ocean for eventual incineration at sea [3] [21]. The stockpile of tactical herbicides in South Vietnam were transported to Bien Hoa Air Force base, re-barreled in 1971 and 1972, and shipped to Johnston Island in the Pacific Ocean. Twenty thousand barrels of tactical herbicides were shipped and stored for 5 years on the Johnston Island beach and then incinerated on a ship in 1977.

Agent Blue, the arsenic-based herbicide, was not burned do concerns related to its high concentrations of arsenic [21]. If incineration at sea, arsenic can become arsine, a toxic gas, especially under reducing conditions. Thus, arsenic was not a good candidate for disposal at sea by incineration. The Agent Blue stored in Vietnam and at Johnston Island (Figure 35) were shipped to Davis-Monthan Air Force Base (Figure 52), where obsolete military planes are permanently stored. The grounds crew routinely sprayed Agent Blue along the perimeter fence and around the decommissioned airplanes to keep the weeds down and to dispose of the remaining Agent Blue stockpiles.

A General Accounting Office (GAO) review of DOD and VA documents [28] identified multiple examples of incomplete and inaccurate information on the DOD’s list of tactical herbicide test and storage sites such as Kelly Air Force Base in Texas. GAO obtained command histories and original DOD reports that provided operational details about the procurement, distribution, use, and disposition of Agent Orange [25] and its components, 2,4-D and 2,4,5-T containing unknown amount of dioxin TCDD [58] [59] [60] [61]. GAO concluded that there was extensive documentation on the herbicide management program at Kelly Air Force Base during the American Vietnam War and more specifically years 1966-1973. According to an Air Force Logistics Command’s Office of History monograph, the command directly responsible for managing Agent Orange was the Directorate of Aerospace Fuels at the San Antonio Air Material Area located at Kelly Air Force base [28].

During the Vietnam War, Kelly Air Force base was also a subcomponent of the U.S. Air Force Logistics Command. GAO documentation shows that quantities of the two components of the tactical herbicide Agent Orange were stored at Kelly Air Force base in Texas in 1972. There were 38,940 gallons of 2,4,5-T containing and unknown amounts of TCDD and 106,260 gallons of 2,4-D stored on the base [28]. The uneven quantities of these two herbicides suggest that not all the tactical herbicides in storage were pre-mixed (50% 2,4-D: 50% 2,4,5-T) to form Agent Orange.

Was Agent Blue destroyed in Kelly Air Force base burn pits [28] ? If so, the smoke coming from the burn pits could become an environmental problem since the particulate and ash would have contained toxic arsenic contaminants and aerosols. The military base personnel could have been exposed to and inhaled arsenic laden smoke. Was it buried in the soils at Kelly Air Force base? If so, the water soluble As would eventually leak from the barrels in the last 50 years and into the groundwater. If so, the military base personnel could have been exposed to arsenic and some Kelly Air Force Base Vietnam Era Veterans [51] have already filed VA claims for benefits because of exposure to either dioxin TCDD or arsenic [50]. The fourth option would have been to transport the Agent Blue to Davis-Monthan Air Force Base in Tucson, Arizona for weed control around the aircraft and perimeter fence. Agent Blue barrels were shipped from southern Vietnam directly and from Johnston Island indirectly [21] between 1972 and 1977. So how did the DOD use up or destroy all of the arsenic-based Agent Blue left over from the American Vietnam War, including the storage stockpile at Kelly Air Force base in Texas, after DOD stopped the spraying of all tactical herbicides in 1971?

1) Agent Orange Dioxin TCDD Human Health Consequences

By 1953, the chemical companies, including BASF, had also discovered the dioxin TCDD health effects on workers after an explosion [58] but were slow to inform the U.S. Government and Military of the extent and magnitude of the dioxin TCDD contaminant in Agent Orange after the combustion temperature was raised 5˚C (9˚F) [3] [7]. Dioxin TCDD by-product was also in other tactical herbicides with associated risks to the environment and human health [10] [60]. This delay in notifying the U.S. Government and Military may have increased the 11 chemical companies’ past, current, and future legal exposure [7]. By the late 1950s, the U.S. Government and Military became fully aware of the environmental and health consequences of the contaminant dioxin TCDD [58] - [63]. On April 15, 1970 the DOD announced that the use of Agent Orange was suspended. Two brigades of the Americal Division continued to use Agent Orange for crop destruction in violation of the suspension. The military officers were later disciplined. The defoliation and crop destruction was fully stopped on June 30, 1971 [25]. The DOD ordered all tactical to be removed from southern Vietnam. What happened to the stockpiles of tactical herbicides in Thailand, Laos and Korea? Were they also shipped to Johnson Island?

2) Impact of Agent Blue (Arsenic) on Human Health

Drinking water and consuming rice are considered the two major pathways to potentially high daily levels of arsenic intake [62]. Vietnamese military, farmers and civilians were at risk of arsenic exposure from contaminated groundwater supplies, long-term diets of daily rice with trace amounts of arsenic, and rice and vegetable crops produced in soil with significant arsenic concentrations. Water and food supplies were critical to U.S. and South Vietnamese military and Vietnamese civilians during the Vietnam War.

Arsenic toxicity and health effects are complex and the impact of Agent Blue on human health was not well known for many years. Post-Vietnam War, arsenic-based industrial wood preservatives and herbicides with cacodylic acid were used throughout the U.S. in wood products, golf course management, cotton fields and drying out agricultural plants prior to harvesting [9]. Today, none of these herbicides is commercially available with the exception of the weed killer monosodium meta-arsonate (MSMA) for use on U.S. cotton [9]. The frequent use of manufactured arsenic products in industry and agriculture has resulted in human exposure by way of inhalation, contaminated drinking water, and food. Epidemiological evidence and animal studies show excessive risks of lung and skin cancers as well as delayed health effects at relatively high exposure rates [21] [60].

The spraying of arsenic-based Agent Blue was field tested in United States, Puerto Rico, Canada and Thailand. Often, Agent Blue was used at full strength during the Vietnam War. The Cancer Assessment Group of EPA currently puts arsenic in the top category of cancer-causing chemicals. Arsenic, even at low doses has been found to be responsible for lung, bladder, and liver cancer, and arsenic is able to cross the placenta to create cancers in the fetus as well. Both birth defects and childhood cancers have been linked to arsenic. The effects of arsenic are delayed and can take decades to appear in humans [45]. Arsenic can cause damage to human DNA, which can adversely affect future offspring. Arsenical herbicides containing cacodylic acid as active ingredients are still used today as weed killers and crop desiccants. Less toxic formations of arsenical herbicides sold over the counter today can cause headaches, vomiting, dizziness, profuse and watery diarrhea, followed by dehydration, electrolyte imbalance, and gradual fall in blood pressure, convulsions, stupor, general paralysis, and possible death in 3 to 14 days [62] [63].

The New Jersey Department of Health and the EPA regard sodium cacodylate as a Special Health Hazard. The Agency for Toxic Substances and Disease Registry suggests, “Arsenic cannot be destroyed once added to the environment”. Therefore, the arsenic amounts (1,232,400 kg of arsenic) U.S. and Republic of Vietnam militaries added when spraying Agent Blue during the Vietnam War, have increased the arsenic load in Mekong Delta and southern Vietnam environment. Arsenic caused additional health effects in humans and animals. Water-soluble arsenic can get into the surface water, soil, and groundwater from applications of Agent Blue on the rice paddies. After the Vietnam War vast amounts of arsenic laced groundwater was pumped to the surface for rice paddies, shrimp ponds and for the water needs of the 15 million people living on the Mekong Delta.

3) Human Health Consequences

On January 8, 1979 Victor J. Yannacone, filed a class action suit, re Agent Orange Product Liability Litigation (1979-1984) on behalf of all the Vietnam veterans that were exposed to Agent Orange containing dioxin and other tactical herbicides. By the end of the year, Yannacone and associates represented 8300 Vietnam veteran clients in a lawsuit against 11 chemical companies including: Dow Chemical, Thompson-Hayward, Diamond Shamrock, Hercules Inc., Monsanto, Ansul Company (the manufacturer of Agent Blue), Riverdale Chemical Company, Uniroyal, Occidental Petroleum, Hooker Chemical Company and N.A. Phillips [3].

The chemical companies argued in federal court that the U.S. government was responsible for the injuries claimed by the veterans and their families. In addition, the companies argued that the government controlled the manufacturing, distribution, and application of Agent Orange (and other tactical herbicides including Agent Blue), some of which included dioxin (TCDD) although military contracts were thought to protect the chemical companies. The U.S. Government having sovereign immunity was eventually dismissed from the case [21].

In May 1984, the Vietnam War Veterans and chemical manufactures settled out of court for $180 million. These chemical companies could then renounce liability even though they knew about the toxic effects of by-product dioxin (or TCDD) [16]. However, the effects of arsenic were not addressed or its affects were combined with dioxin TCDD. Raising the heating temperature during the manufacture of Agent Orange to accelerate chemical reactions during the manufacturing process increased the dioxin TCDD levels up to 3000 times of commercial production thereby magnifying the toxicity of Agent Orange [13].

Although the manufacturing process for Agent Blue was different, this did not affect the inherent toxicity of arsenic by itself. Many of the 52,000 Vietnam Veterans were dissatisfied with the amount of the settlement ($3800.00/veteran or the family). The judge ruled the out of court settlement was fair. The funds were dispensed by 1997. After the settlement, the U.S. Government established an Endocrine Disruptor Screening Program to test industrial and agricultural chemicals for endocrine effects prior to marketing and use. The goal was to prevent future unanticipated consequences of the use of a new chemical or herbicide [7].

The Agent Orange Product Liability Litigation (1979-1984) records retained by the New Jersey State Council, Vietnam Veterans of America, Inc. were transferred in 1000 legal boxes to the Vietnam Center and Archive (VNCA) at Texas Tech University (personal communication from Executive Director Stephen Maxner) and are of immense importance to furthering understanding of how tactical herbicides with dioxin (TCDD) and Agent Blue with arsenic were manufactured and deployed during the Vietnam War. This specific collection is unique as it represents the years of document and material collection in preparation for the landmark, “Agent Orange” legal action with regard to its contamination with dioxin and could include information and records about other tactical herbicides including Agent Blue.

The resulting out-of-court settlement was of crucial importance in providing countless Vietnam veterans, and their families, exposed to dioxin and perhaps arsenic with much needed financial support and restitution. The settlement also resulted in the temporary storage of nearly 1000 boxes of materials that provide detailed information regarding the eleven chemical manufacturers involved in tactical herbicide production and also included Ansul Chemical Company, which manufactured Agent Blue [21]. These documents are the most comprehensive collection of military and government historical documents detailing the use and storage of Agent Orange and other potentially dioxin contaminated tactical herbicide defoliants and/or arsenic based herbicide (Agent Blue) throughout the entire Vietnam War.

The Vietnam Center and Sam Johnson Archive submitted proposals in 2019 and 2020 (to National Academy of Humanities) to electronically scan the hundreds of thousands of documents. The collection will undoubtedly provide additional details pertinent to ongoing environmental and human health studies of tactical herbicide remediation programs in Vietnam, Thailand, Korea, and the United States including various storage facilities on wartime military bases as well as U.S. chemical manufacturing sites, such as Newark, New Jersey; Marinette, Wisconsin; and Menominee, Michigan.

Ansul and other chemical companies were named as defendants in a 2005 lawsuit alleging that the use of the tactical herbicides by the U.S. military led to serious birth defects for Vietnamese children (Figure 53) and (Figure 54) and perhaps the U.S. military Vietnam veterans’ children. The United States District Court for the Eastern District of New York ruled that the eleven defending companies were manufacturing tactical herbicides under the direct order of three Presidents of the United States and could not be sued for the consequences of the use of their herbicide products [21]. The court also ruled that the British had previously used Agent Orange (with the by-product dioxin TCDD) during the 1950s Malayan Emergency and that they set the precedent for America’s use in the Vietnam War.