Agent Name


Alternative Name


CAS Number




Major Category



MCPP; (+)-alpha-(4-Chloro-2-methylphenoxy) propionic acid; (+-)-2-((4-Chloro-o-tolyl)oxy)propionic acid (8CI); 2-(2-Methyl-4-chlorophenoxy)propanoic acid; 2-(2-Methyl-4-chlorophenoxy)propionic acid; 2-(2-Methyl-4-chlorphenoxy)-propionsaeure [German]; 2-(4-Chloor-2-methyl-fenoxy)-propionzuur [Dutch]; 2-(4-Chlor-2-methyl-phenoxy)-propionsaeure [German]; 2-(4-Chloro-2-methylphenoxy)propanoic acid; 2-(4-Chloro-2-methylphenoxy)propionic acid; 2-(4-Chloro-2-tolyloxy)propionic acid; 2-(4-Chloro-o-tolyl)oxylpropionic acid; 2-(4-Chlorophenoxy-2-methyl)propionic acid; 2-(p-Chloro-o-tolyloxy)propionic acid; 2-MCPP; 2M 4KhP; 2M-4CP; 2M4KhP; 4-Chloro-2-methylphenoxy-alpha-propionic acid; Acide 2-(4-chloro-2-methyl-phenoxy)propionique [French]; Acido 2-(4-cloro-2-metil-fenossi)-propionico [Italian]; Anicon B; Anicon P; CMPP; Celatox CMPP; Chipco turf herbicide mcpp; Compitox; FBC CMPP; Iso-Cornox; Isocarnox; Kilprop; Kwas 4-chloro-2-metylofenoksypropionowy [Polish]; Kyselina 2-(4-chlor-2-methylfenoxy)propionova [Czech]; Liranox; MCPP; Mechlorprop; Mecomec; Mecopar; Mecopeop; Mecoper; Mecopex; Mecoturf; Mecprop; Mepro; Methoxone; Morogal; N.b. mecoprop; Okultin MP; Propionic acid, 2-(2-methyl-4-chlorophenoxy)-; Propionic acid, 2-(4-chloro-2-methylphenoxy); Proponex-plus; RD 4593; Rankotex; Runcatex; SYS 67 Mecmin; U 46 KV Fluid; Vi-Par; Vi-Pex; alpha-(2-Methyl-4-chlorophenoxy)propionic acid; [ChemIDplus] UN2765


Herbicides, Chlorophenoxy


Colorless to brown solid; [ICSC] Tan powder with lumps; [MSDSonline]


Used as selective post-emergence herbicide for control of broad-leaved weeds in wheat, barley, oats, herbage seed crops, grassland, under fruit trees and vines, and sport and ornamental turf; [HSDB] Mecoprop is a 50:50 ratio mixture of the R and S isomers of 2-(4-chloro-2-methylphenoxy)propanoic acid; Mecoprop is being replaced in the US by Mecoprop-p, which is the R isomer and the active isomer; [Reference #1]


A skin and eye irritant; [Hawley] A skin, eye, and respiratory tract irritant; Can be absorbed through skin; "Mecoprop is a chlorophenoxy-herbicide which, as a group, has been classified by IARC (1987) as possibly carcinogenic to humans, but the data on this specific substance are inconclusive." [ICSC] Causes increased liver enzymes in rat studiies; [Reference #1] An irritant; May cause serious eye injury; Can be absorbed through skin; [MSDSonline] See "2,4-D." See "Mecoprop-p" and "Mecoprop dimethylamine salt."

Reference Link

EPA Pesticide Chemical Search

Exposure Assessment
Vapor Pressure

2.3E-6 mm Hg

Explanatory Notes

The Guide in the Emergency Response Guidebook is for "Phenoxy pesticide, solid, toxic."

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

Biomedical References

Search PubMed

Related Information in HazMap

Industrial Processes with risk of exposure: