Agent Name

2,4-D 2-Ethylhexyl ester

CAS Number




Major Category



2-Ethylhexyl 2,4-dichlorophenoxyacetate; 2,4-D-2-ethylhexyl; (2,4-Dichlorophenoxy)acetic acid 2-ethylhexyl ester; 2-Ethylhexyl (2,4-dichlorophenoxy)acetate; Acetic acid, (2,4-dichlorophenoxy)-, 2-ethylhexyl ester; [ChemIDplus] 2,4-D 2-EHE; [Reference #1]


Herbicides, Chlorophenoxy


Golden yellow liquid; [HSDB] Amber to light brown liquid with phenolic odor; [MSDSonline]


Used as selective herbicide for control of broad-leaved weeds in cereal and grass seed crops, pasture, lawn, turf, and uncultivated land; [ExPub: CPS&Q: IUCLID]


A skin and eye irritant; The esters of 2,4-D are hydrolyzed rapidly in the body to 2,4-D; Do not accumulate in mammals; Plasma half-life is about 1 day; Analysis of 2,4-D as esters and amine salts in 1982 found the esters more highly contaminated with dioxins; [HSDB] Toxic to rats after oral doses of 300 mg/kg/day for 14 weeks (same results for 2,4-D and the 2-ethylhexyl ester); NOEL = 15 mg/kg/day; Long-term toxicity studies are not necessary; Any 2,4-D compound absorbed is hydrolyzed to 2,4-D by esterase enzymes in the gut, plasma, liver, and skin; Food consumption markedly decreased in high-dose animals; High-dose animals had other changes: lower hemoglobin, higher liver enzymes, lower organ weights (including testes, ovaries, and thymus), higher organ weights (liver and kidneys), eye cataracts, thyroid hypertrophy, and bone marrow hypoplasia; [Reference #1] Formerly identified as the isooctyl ester; The acid form (2,4-D) is used as representative of the salts and esters due to close similarities in relative toxicities; Not irritating to skin or eyes; [Reference #2] Chlorophenoxy herbicides are possibly carcinogenic to humans (Group 2B); [IARC] See "2,3,7,8-Tetrachlorodibenzo-p-dioxin." See "2,4-D."

Exposure Assessment
Vapor Pressure

0.000359 mm Hg

Lethal Concentration

LC50 (rat) > 5,400 mg/m3

Reference Link

EPA Pesticide Chemical Search

Adverse Effects

Hepatotoxin, Secondary

Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information


Chemical Information

Search ChemIDplus

Related Information in HazMap

Industrial Processes with risk of exposure: