Agent Name

Mecoprop dimethylamine salt

CAS Number




Major Category



2-(2-Methyl-4-chlorophenoxy)propionic acid, dimethylamine salt; Mecoprop-dimethylammonium; Propionic acid, 2-((4-chloro-o-tolyl)oxy)-, dimethylamine salt; Dimethylammonium 2-(4-chloro-2-methylphenoxy)propionate; Propanoic acid, 2-(2-methyl-4-chlorophenoxy)-, dimethylamine salt; Propanoic acid, 2-(4-chloro-2-methylphenoxy)-, compd. With N-methylmethanamine (1:1); Dimethylamine 2-(2-methyl-4-chlorophenoxy)propionate; [ChemIDplus] MCPP-4 Amine; DMA Salt of MCPP; Dimethylamine salt of 2-(2-methyl-4-chlorophenoxy)propionic acid; [Riverdale MSDS]


Herbicides, Chlorophenoxy


Product in 48% water and inert ingredients: Dark amber liquid with a slight amine odor; [Riverdale MSDS]


Used as a plant growth regulator (herbicide); A 50:50 mixture of the R and S isomers of 2-(4-chloro-2-methylphenoxy)propanoic acid (Mecoprop or MCPP); The R isomer has been identified as the herbicidally active isomer and with advances in chemical synthesis can now be affordably commercially manufactured; This enriched isomeric form is being called Mecoprop-p (MCPP-p) and is replacing the racemic mixture in all formulations being used in the US; [Reference #1]


Product in 48% water and sequestrants (inert ingredients): A minimal skin irritant; Not a skin sensitizer; Harmful by skin absorption; Ingestion may cause muscle weakness, nausea, abdominal pain, hypotension, myotonia, or death; The concentrated product is a severe eye irritant that may cause permanent injury; Prolonged or repeated exposure to phenoxy herbicides may cause adverse effects to liver, kidney, GI tract, and muscular system; [Riverdale MSDS] See "Mecoprop-p."

Reference Link

EPA REDs: Mecoprop-p (MCPP-p) - 2007

Exposure Assessment
Lethal Concentration

LC50 (rabbit) > 4,000 mg/m3

Adverse Effects

Hepatotoxin, Secondary

Links to Other NLM Databases
Toxicity Information

Chemical Information

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Related Information in HazMap

Industrial Processes with risk of exposure: