Waiting for an Army to Die (28 page)

April 1978

EPA issues notice of Rebuttal Presumption Against Registration (RPAR) for 2,4,5-T.

February 1979

EPA issues order of emergency suspension for 2,4,5-T and 2,4,5-TP (Silvex). First emergency suspension.

Suspend products registered for forestry, right-of-way, pasture, home, aquatic, and recreational area uses of 2,4,5-TP.

EPA initiates cancellation proceedings for 2,4,5-T and 2,4,5-TP suspended uses.

April 1979

Dow fails to win appeal of emergency suspension.

February 1980

EPA cancellation hearings begin. Dow Chemical Corporation and 54 intervenors on their behalf/EPA and 2 intervenors on their behalf.

March 1981

EPA agrees with Dow-initiated motion for suspending cancellation hearings, and begins closed-door meetings to pursue out-of-hearing settlement.

51. General. Antiplant agents are chemical agents which possess a high offensive potential for destroying or seriously limiting the production of food and defoliating vegetation. These compounds include herbicides that kill or inhibit the growth of plants; plant growth regulators that either regulate or inhibit plant growth, sometimes causing plant death; desiccants that dry up plant foliage; and soil sterilants that prevent or inhibit the growth of vegetation by action with the soil. Military applications for antiplant agents are based on denying the enemy food and concealment.

52. Antiplant Agents in Use.

a. ORANGE
.

(1)
Description
. Agent ORANGE is the Standard A agent. It is composed of a 50:50 mixture of the n-butyl esters of 2,4-D and 2,4,5-T (app D and C1, TM 3-215). ORANGE appears as a dark-brown oily liquid which is insoluble in water but miscible in oils such as diesel fuel. It weighs about 10.75 pounds per gallon and becomes quite viscous as the temperature drops, solidifying at 45°F. It is noncorrosive, of low volatility, and nonexplosive, but deteriorates rubber.

(2)
Rate of application
. The recommended rate of application of ORANGE is 3 gallons per acre. This may vary depending on the type of vegetation (app C). In some situations better coverage may be obtained by diluting ORANGE with diesel fuel oil, which results in a less viscous solution that is dispersed in smaller droplets. Dilution may also be required when using dispersion equipment which does not permit the flow rate to be conveniently adjusted to 3 gallons per acre. See discussion of application methods in paragraphs 57 and 58.

(3)
Effect on foliage
. ORGANGE penetrates the waxy covering of leaves and is absorbed into the plant system. It affects the growing points on the plant, resulting in its death. Rains occurring within the first hours after spraying will not reduce the effectiveness of ORANGE to the
extent that they reduce the effectiveness of aqueous solutions. Broadleaf plants are highly susceptible to ORANGE. Some grasses can be controlled but require a much higher dose rate than broadleaf plants. Susceptible plants exhibit varying degrees of susceptibility to ORANGE. Death of a given plant may occur within a week or less, or may require up to several months depending on the plant’s age, stage of growth, susceptibility, and the dose rate. See employment considerations in paragraphs 53 through 55.

(4)
Safety precautions and decontamination
. ORANGE is relatively nontoxic to men or animals. No injuries have been reported to personnel exposed to aircraft spray. Personnel subject to splashes from handling the agent need not be alarmed, but should shower and change clothes at a convenient opportunity. ORANGE is noncorrosive to metals but will remove aircraft paint and walkway coatings. Contaminated aircraft should be washed with soapy water to remove the agent. Rubber hoses and other rubber parts of transfer and dissemination equipment will deteriorate and require replacement, since ORANGE softens rubber.

b. BLUE (Phytar 560G)
.

(1)
Description
. Agent BLUE is an aqueous solution containing about 3 pounds per gallon of the sodium salt of cacodylic acid, the proper amount of surfactant (a substance which increases the effectiveness of the solution), and a neutralizer to prevent corrosion of metal spray apparatus. BLUE is the agent normally used for crop destruction.

(2)
Rate of application
. BLUE may be sprayed as received from the manufacturer without dilution, if desired. The recommended application rate for crop destruction is about 1 to 2 gallons per acre (app C). However, much higher use rates of BLUE are required to kill tall grasses, such as elephant grass or sugarcane because of the large masses of vegetation. For hand-spray operations, 2 gallons of BLUE diluted with water to make 50 gallons will give a solution that can be dispersed by hand at a rate equivalent to approximately 1 to 3 gallons of pure agent per acre.

(3)
Effect on foliage
. Enough BLUE applied to any kind of foliage will cause it to dry and shrivel, but the agent is more effective against grassy plants than broadleaf varieties. Best results are obtained when the plant is thoroughly covered, since the agent kills by absorption of moisture from the leaves. The plants will die within 2 to 4 days or less and can then be burned if permitted to dry sufficiently. BLUE in low dose rates can also prevent grain formation in rice without any apparent external effect. The plant develops normally but does not yield a crop. Spray rates higher than
about one-half gallon per acre usually kill the crop. Although BLUE can produce relatively rapid defoliation, regrowth may occur again in about 30 days. Repeated spraying is necessary to provide a high degree of continuous plant kill.

(4)
Safety precautions and decontamination
. Normal sanitary precautions should be followed when handling BLUE. Although it contains a form of arsenic, BLUE is relatively nontoxic. It should not be taken internally, however. Any material that gets on the hands, face, or other parts of the body should be washed off at the first opportunity. Clothes that become wet with a solution of BLUE should be changed. Aircraft used for spraying this solution should be washed well afterward. When WHITE is added to BLUE, a precipitate forms that will clog the system. If the same spray apparatus is to be used for spraying agents WHITE and BLUE, the system must be flushed to assure that all residue of the previous agent is removed.

c. WHITE (Tordon 101)
.

(1)
Description
. The active ingredients of agent WHITE are 20 percent picloram and 80 percent isopropylamine salt of 2,4-D. Active ingredients constitute about 25 percent of the solution. A surfactant is also present. WHITE is soluble in water, noncorrosive, nonflammable, nonvolatile, immiscible in oils, and more viscous than ORANGE at the same temperatures.

(2)
Rate of application
. WHITE usually should be applied at a rate of 3 to 5 gallons per acre on broadleaf vegetation. However, the rate may vary depending on the type of flora. Quantities required to control jungle vegetation may vary from 5 to 12 gallons per acre. This quantity exceeds the spray capability of most aircraft spray systems for a single pass. It is usually unfeasible in large-scale military operations to apply such large volumes. For ground-based spray operations, however, high volumes are necessary. Hand-spray operations cannot evenly cover a whole acre with only 3 gallons of solution. Three gallons of WHITE diluted to a 30-gallon solution can be more easily sprayed over an area of one acre. The manufacturer recommends diluting WHITE with sufficient water to make a 10-gallon solution for each gallon of agent.

(3)
Effect on foliage
. WHITE kills foliage in the same manner as ORANGE, since 80 percent of the active ingredient is 2,4-D. PICLORAM is more effective than 2,4-D, but acts slower. WHITE is effective on many plant species, and equal to or more effective than ORANGE on the more woody species. The material must be absorbed
through the leaves. The water solution does not penetrate the waxy covering of leaves as well as oily mixtures and is more easily washed off by rain.

(4)
Safety precautions and decontamination
. WHITE exhibits a low hazard from accidental ingestion. However, it may cause some irritation if splashed into the eyes. Should eye contact occur, flush with plenty of water. Splashes on the skin should be thoroughly washed with soap and water at the first opportunity. Contaminated clothing should be washed before reuse. When WHITE is used in the same equipment as BLUE, all of the WHITE should be removed before using BLUE. The two agents produce a white precipitate that will clog spray systems.

SOURCE:
Military Assistance Command Vietnam Reports
.

Directors, VA hospitals, domiciliary, outpatient clinics, and regional offices with outpatient clinics.

Subject: Potential exposures of veterans to chemical defoliants during the Vietnam War.

1. During the Vietnam War, herbicidal war chemicals were utilized for defoliation of vegetation. Recently concern has developed among some scientific and other groups that these chemicals may be capable of producing adverse health effects on individuals who were exposed to the herbicides. Because of their potential impact on a segment of the veteran population, the VA is attempting to develop accurate information on the health-related effects of the defoliants utilized during the Vietnam War.

2. The four defoliants utilized regularly were picloram, cacodylic acid, 2,4-D and 2,4,5-T. These were mixed in variable proportions and placed in color-coded storage drums which were identified as “Agent Orange,” “Agent White,” “Agent Blue,” and “Agent Purple.” A large number of studies performed on man and several animal species have demonstrated that the four herbicides have a low level of toxicity, both individually and when mixed. Furthermore they appear to be rapidly absorbed and completely excreted in both the human and the animal.

3. Humans exposed repeatedly to these agents may experience temporary and fully reversible neurological symptoms; however, the only chronic condition definitely associated with such exposure in humans is chloracne. Comprehensive animal studies performed under experimental conditions have demonstrated that very massive doses of these agents produce fatty degeneration of solid organs, gastrointestinal disturbances and thymic atrophy, all of which were reversible after withdrawal of the chemicals.

4. These studies have failed to confirm the suggestion in the Vietnamese medical literature that liver cancer, frequent abortions, and fetal birth defects occur among those exposed to the defoliants. In addition,
no confirmation has been obtained for the experimental studies of one scientist who found that hepatic and pancreatic cancers followed prolonged exposure to one of the chemicals.

5. In contrast to the apparent low toxicity of the four defoliants evidence has been adduced that a contaminant called dioxin found in some of the storage drums has a significant potential toxicity. Although its concentration of dioxin was variable in different drums, it was always found in minute quantities. Experimental evidence from animal studies indicates that this chemical is eliminated from the body fairly rapidly and that it produces its toxic effects rather promptly. All available data suggests that it is not retained in tissues for prolonged periods of time. Accordingly, the recent suggestion by some observers that dioxin might still be detected in the fat tissues of Vietnam veterans exposed to it appears to be implausible.

6. Despite the generally negative results of human and animal studies of the toxicity potential of the Vietnam defoliants, a great deal of concern has been engendered among veterans and their families by media presentations on these agents. The VA is responding to these concerns by working collaboratively with appropriate experts from the federal and private sectors in order to more adequately define the potential human toxicity of the defoliants for humans. You will be periodically informed concerning the results of these efforts.

7. Meanwhile, we request that all VA staff who are called upon to deal with veterans who are concerned about toxic effects from a possible exposure to the defoliants adhere to the following protocol: