2,4-D
Trade and Other Names:2,4-D is used in many commercial products. Commercial names for products containing 2,4-D include Aqua-Kleen, Barrage, Lawn-Keep, Malerbane, Planotox, Plantgard, Savage, Salvo, Weedone, and Weedtrine-II.
Chemical Class: phenoxy compound
Introduction: There are many forms or derivatives of 2,4-D including esters, amines, and salts. Unless otherwise specified, this document will refer to the acid form of 2,4-D. 2,4-D, a chlorinated phenoxy compound, functions as a systemic herbicide and is used to control many types of broadleaf weeds. It is used in cultivated agriculture, in pasture and rangeland applications, forest management, home, garden, and to control aquatic vegetation. It may be found in emulsion form, in aqueous solutions (salts), and as a dry compound.
The product Agent Orange, used extensively throughout Vietnam, was about 50% 2,4-D. However, the controversies associated with the use of Agent Orange were associated with a contaminant (dioxin) in the 2,4,5-T component of the defoliant.
Formulation: It may be found in emulsion form, in aqueous solutions (salts), and as a dry compound.
Physical Properties:
Appearance: 2,4-D is a white powder.
Chemical Name: (2,4-dichlorophenoxy)acetic acid
CAS Number: 94-75-7
Molecular Weight: 221.04
Water Solubility: 900 mg/L @ 25 C (acid)
Solubility in Other Solvents: ethanol v.s.; diethyl ether v.s.; toluene s.; xylene s.
Melting Point: 140.5 C
Vapor Pressure: 0.02 mPa @ 25 C (acid)
Partition Coefficient: 2.81
Adsorption Coefficient: 20 (acid)
Exposure Guidelines:
ADI: 0.3 mg/kg/day
MCL: 0.07 mg/L
RfD: 0.01 mg/kg/day
PEL: 10 mg/m3 (8-hour)