Information on Chemical Usage

Several types and combinations of chemicals were used in Operation Ranch Hand, each one codenamed by the color of the identification stripe that appeared on its chemical storage drums. The best known mixture is popularly known as Agent Orange, although in the military it was referred to as Herbicide Orange (HO). All the herbicide mixtures were contaminated with varying levels of toxic chemicals, the most notorious and toxic of which was 2,3,7,8-tetrachlorodibenzodioxin (TCDD), often just called dioxin. Dioxin was found in Agents Orange, Green, Pink, and Purple. TCDD is an extremely toxic chemical, linked to a variety of diseases.

Table 1. Chemical breakdown, estimated quantities and duration of military herbicides used in Vietnam, 1961-1971.*1,2,3
Name Chemical Constituents Concentration of Active Ingredient Years Used Documented Quantities Sprayed
Phenoxyacetic Acid Based HerbicidesĀ§
Agent Pink* 60%-40% n-Butyl: Isobutyl ester of 2,4,5-Ta 961-1081 g/l acid equivalent 1961,1965b At least 50,312
Agent Green* n-Butyl ester 2,4,5-T 1961,1965c 31,026 shown on procurement records
Agent Purple* 50% n-Butyl ester 2,4,-D; 30% n-Butyl ester 2,4,5-T; 20% Isobutyl ester 2,4,5-T 1033 g/l acid equivalent 1962-1965 1,892,773
Agent Orange* 50% n-Butyl ester 2,4,-D; 50% n-Butyl ester 2,4,5-T 1033 g/l acid equivalent
Agent Orange* II 50% n-Butyl ester 2,4-D; 50% Isooctyl ester 2,4,5-T (Assumed same as Orange) After 1968 At least 3,591,000 shipped. Quantity sprayed not known
Agent Whited Based on weight of acid: 21.2% Tri-isopropanolamine salts of 2,4-De and 5.7% Picloram; with water, wetting agent and other inerts for remainder By acid weight: 240.2 g/l 2,4,-D and 64.9 g/l Picloram 1966-1971 20,556,525
Agent Blue (powder)f Cacodylic acidg and sodium cacodylate Acid: 65% active ingredient
Salt: 70% active ingredient
Agent Blue (H2O solution) 21% sodium cacodylate plus additional cacodylic acid to yield not less than 26% total acid equivalent on weight basis; by volume: 3-5% sufactant; 0.5% antifoam agent. Cacodylic acid weight: 360.3 g/l 1964-1971
* Other chemicals used in testing program but not in Vietnam operations include: "Modified Orange (picloram added to Orange); Dalapon; Bromacil; Tandex; Monuron; Diuron; Maleic hydrazide
Ā§ 1890 l Dinoxol (butoxyethanol esters of 2,4-D and 2,4,5-T), 1455 l Trinoxol (40% ethanol ester of 2,4,5-T) and 378 l Conc D (30% ethyl ester of 2,4,-Dichlorophenoxyacetic acid in H20) were used in tests udring 1961.
*Contaminated with varying levels of 2,4,7,8-tetrachlorodibenzodioxin (TCDD).
a 2,4,5-Trichlorophenoxyacetic acid
b 80-20% mixture when mixed with Agent Green.
c Immediately mixed with Agent Pink, yields a 60-40% mixture of constituents of Agent Pink.
d Proprietary product of Dow Chemical Company (Tordon 101). Picloram is 4-Amino-3,5,6-trichloropicolinic acid.
e 2,4-Dichlorophenoxyacetic acid
f Ansul Chemical Co. product Phytar 560 was only arsenical used prior to July 1969.
g Dimethylarsinic acid

Table 2 shows all herbicides sprayed over the Republic of South Vietnam between 1962-1971 by volume, type and year. These data are based our the corrected version of the HERBS file developed by the Stellman team, under contract to the US National Academy of Sciences. This table does not contain the small amounts of the 2,4,5-T/2,4-D mixtures known as Dinoxol and Trinoxol, and sprayed during tests carried out in 1961.

Table 2. Liters and per cent distribution of herbicides sprayed in the Republic of South Vietnam, 1962-1971, by agent2 and year of spraying.1
Year Purple Pink Orange White Blue Unstated Total
1962 142085 10031 152117
1963 340433 340433
1964 831162 15619 846781
1965 579092 50312 1868194 18927 2516525
1966 7602390 2179450 59809 126474 9968124
1967 12528833 5141117 1518029 86288 19274267
1968 8747064 8353143 1289144 249750 18639101
1969 12679579 3987100 1035385 274291 17976356
1970 2251876 845464 762665 96509 3956514
1971 50251 50698 9085 110034
TOTALS 1892773 50312 45677937 20556525 4741381 861325 73780253
Percent 2.6 0.1 61.9 27.9 6.4 1.2 100
1. Data are taken from corrected HERBS file.
2. Data do not include 947 l Dinoxol and 548 l Trinoxol sprayed during tests in 1961.