2-Methyl-4-chlorophenoxybutyric acid

Agent Name
2-Methyl-4-chlorophenoxybutyric acid
Alternative Name
MCPB
CAS Number
94-81-5
Formula
C11-H13-Cl-O3
Major Category
Pesticides
2-Methyl-4-chlorophenoxybutyric acid formula graphical representation
Synonyms
MCPB; (4-Chloro-o-tolyloxy)butyric acid; 2,4-MCPB; 2M 4KhM; 4-((4-Chloro-o-tolyl)oxy)butyric acid; 4-(2-Methyl-4-chlorophenoxy)butyric acid; 4-(2-Methyl-4-chlorphenoxy)-buttersaeure [German]; 4-(4-Chlor-2-methylphenoxy)-buttersaeure [German]; 4-(4-Chloro-2-methylphenoxy)butanoic acid; 4-(4-Chloro-2-methylphenoxy)butyric acid; 4MCPB; Bexone; Kyselina 4-(4-chlor-2-methylfenoxy)maselna [Czech]; Legumex; MCP-butyric; PDQ; Thitrol; Trifolex; Trotox; U46 MCPB; gamma-(4-Chloro-2-methylphenoxy)butyric acid; gamma-MCPB; [ChemIDplus]
Category
Herbicides, Chlorophenoxy
Description
Colorless or white solid; Technical product is beige to brown solid; [HSDB] Cream to pale brown solid; [MSDSonline]
Sources/Uses
Used as post-emergence herbicide for weed control in green peas, spring cereals, seedling clovers, maize, and pastures; [HSDB] Registered for use on green peas and dry peas before flowering; [Reference #1]
Comments
A strong eye and mucous membrane irritant; Effects to enzymes in the liver, brain, and skeletal muscles were observed in acute rat feeding studies; Effects in high-dose sub-chronic feeding studies with dogs include small testicles, decrease in organ weight ratios and spermatogenic activity, tubular atrophy, and immature or atrophic prostate; In sub-chronic feeding studies with rats, no significant toxicological effects were observed; [HSDB] Chlorophenoxy herbicides are possibly carcinogenic to humans (Group 2B); [IARC] See "2,4D."
Reference Link #1
Biomedical References

Exposure Assessment

Vapor Pressure
4.33E-07 mm Hg
Lethal Concentration
LC50 (rat) > 1,140 mg/m3

Adverse Effects

Hepatotoxin
Hepatoxic (a) from occupational exposure (secondary effect) or (b) in animal studies or in humans after ingestion

Diseases, Processes, and Activities Linked to This Agent

Processes

Industrial Processes with risk of exposure: