4- (2,4-dichlorophenoxy) butyric acid

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Structural formula
Structural formula of 4- (2,4-dichlorophenoxy) butyric acid
General
Surname 4- (2,4-dichlorophenoxy) butyric acid
other names
  • 2,4-DB
  • 4- (2,4-dichloro) phenoxybutanoic acid
Molecular formula C 10 H 10 Cl 2 O 3
Brief description

colorless crystals

External identifiers / databases
CAS number 94-82-6
EC number 202-366-9
ECHA InfoCard 100.002.152
PubChem 1489
ChemSpider 1444
Wikidata Q229887
properties
Molar mass 249.09 g mol −1
Physical state

firmly

density

1.46

Melting point

117-119 ° C

boiling point

324.35 ° C

solubility

sparingly soluble in water (4.384 g l −1 at 20 ° C, pH 7)

safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary
07 - Warning 09 - Dangerous for the environment

Caution

H and P phrases H: 302-411
P: 273
Toxicological data

370–1500 mg kg −1 ( LD 50 ,  rat ,  oral )

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

4- (2,4-Dichlorophenoxy) butyric acid (or 2,4-DB for short ) is a chemical compound from the group of halogenated phenoxycarboxylic acids .

properties

2,4-DB decomposes when heated above its melting point. It forms colorless, flammable crystals.

use

Estimated application rate in the USA

2,4-DB is used in crop protection products as an active ingredient in selective herbicides (e.g. for soy and peanuts ). The active metabolite , 2,4-dichlorophenoxyacetic acid , acts as a growth agent herbicide. Its (mostly more easily water-soluble) esters and salts [4- (2,4-dichlorophenoxy) butyrate] are also used as herbicides. These are e.g. B. Dimethylamine salt (CAS number: 2758-42-1), isooctyl ester (CAS number: 1320-15-6) and butoxyethanol ester (CAS number: 32357-46-3).

Admission

In some EU countries, 2,4-DB is approved as a plant protection product , but not in Germany, Austria and Switzerland.

Health hazards

Several studies have shown that dealing with 2,4-DB has a greatly increased risk of developing Parkinson's disease .

Individual evidence

  1. ↑ a b c d e Entry on 4- (2,4-dichlorophenoxy) butyric acid in the GESTIS substance database of the IFA , accessed on February 7, 2017(JavaScript required) .
  2. ↑ a b Entry on 2,4-DB in the Pesticide Properties DataBase (PPDB) of the University of Hertfordshire , accessed on February 22, 2014.
  3. ↑ Entry on 4- (2,4-dichlorophenoxy) butyric acid in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
  4. ↑ Vetpharm: Phenoxycarboxylic acid herbicides
  5. ↑ General Directorate Health and Food Safety of the European Commission: Entry on 2,4-DB in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on March 12, 2016.
  6. ↑ Caroline M. Tanner, G. Webster Ross, Sarah A. Jewell, Robert A. Hauser, Joseph Jankovic, Stewart A. Factor, Susan Bressman, Amanda Deligtisch, Connie Marras, Kelly E. Lyons, Grace S. Bhudhikanok, Diana F Roucoux, Cheryl Meng, Robert D. Abbott, J. William Langston: Occupation and Risk of Parkinsonism - A Multicenter Case-Control Study , Archives of Neurology, Volume 66, Issue 9, September 2009, pp. 1106-1113, doi : 10.1001 / archneurol.2009.195 .
  7. ↑ Alexis Elbaz, Jacqueline Clavel, Paul J Rathouz, Frédéric Moisan, Jean-Philippe Galanaud, Bernard Delemotte, Annick Alpérovitch, Christophe Tzourio: Professional exposure to pesticides and Parkinson disease , Annals of neurology, Volume 66, Issue 4, October 2009, Pp. 494-504, doi : 10.1002 / ana.21717 .

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