Alachlor

Structural formula
	Simplified structural formula - 1: 1 mixture of two atropisomers
General
Surname	Alachlor
other names	2-chloro- N - (2,6-diethylphenyl) - N - (methoxymethyl) acetamide ( IUPAC ) ; Chloroacetic acid- N - (methoxymethyl) -2,6-diethylanilide; 2-chloro-2 ', 6'-diethyl- N - (methoxymethyl) acetanilide; Metachlor;
Molecular formula	C 14 H 20 ClNO 2
Brief description	colorless to gray, flammable, slightly sweet-smelling powder
External identifiers / databases
EC number	240-110-8
ECHA InfoCard	100.036.448
PubChem	2078
Wikidata	Q421204
properties
Molar mass	269.77 g mol −1
Physical state	firmly
density	1.13 g cm −3
Melting point	40-41 ° C
boiling point	100 ° C (at 3 Pa) (decomposition from 105 ° C)
Vapor pressure	2.9 m Pa (25 ° C)
solubility	very bad in water (212 mg l −1 at 20 ° C)
safety instructions
H and P phrases	H: 302-317-351-410
	P: 280-301 + 312 + 330
Toxicological data	930 mg kg −1 ( LD 50 , rat , oral ) ; 3500 mg kg −1 ( LD 50 , rabbit , transdermal ) ;
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Alachlor is a mixture of two atropisomeric chemical compounds from the group of carboxamides and acetanilides . It belongs to the herbicide group of the chloroacetamides and is in the form of a colorless, slightly sweet-smelling powder.

history

Alachlor was first approved in the USA in 1969 and marketed by Monsanto under the name Lasso .

Extraction and presentation

Alachlor is produced by successively reacting 2,6-diethylaniline with formaldehyde , chloroacetic acid chloride and methanolic ammonia solution.

use

Alachlor was used as a selective forerunner herbicide against grass weeds in cabbage, corn, peanut, soybean, cotton, rape and sunflower cultivation. It was often mixed with other herbicides such as atrazine , glyphosate , trifluralin or imazaquin .

Admission

In 2006 the EU Commission decided not to include alachlor in the list of active ingredients in plant protection products approved in the European Union . In Germany and Austria, therefore, no pesticides with this active ingredient are approved. In Switzerland, some pesticides with alachlor were approved in arable farming, but the approvals have now been terminated. Preparations containing alachlor were allowed to be sold there until September 2011, after September 15, 2012 they are no longer allowed to be used.

safety instructions

Alachlor is only slightly toxic, but is classified as potentially carcinogenic. It is particularly toxic to algae, small crustaceans and fish.

Since it can penetrate the groundwater when it is used in crops and through precipitation, residues have been found in food (and are, since it is still used in other countries). In Germany, according to the Maximum Residue Quantity Ordinance (RHmV), rapeseed and beet seeds may contain 0.1 mg / kg, tea and tea-like products 0.05 mg / kg and other plant-based foods 0.2 mg / kg.

proof

Alachlor can be detected by solid phase extraction and subsequent GC / ECD analysis up to a detection limit of 0.025 µg / l. For reliable qualitative and quantitative determinations, the coupling processes between HPLC , gas chromatography and mass spectrometry are used today after suitable sample preparation .

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Entry on alachlor in the GESTIS substance database of the IFA , accessed on January 8, 2020(JavaScript required) .
↑ ^a ^b ^c WHO / FAO Data Sheet on Pesticides (PDS) for Alachlor , accessed December 9, 2014.
↑ Entry on alachlor 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 .
↑ Pesticide Reregistration Sheet (English) ( Memento from December 9, 1999 in the Internet Archive ) (PDF; 45 kB).
↑ ^a ^b ^c ^d Emission reduction for priority and priority hazardous substances of the Water Framework Directive - Material data sheets - Data sheet Alachlor . Texts 29/07, Environmental Research Plan of the Federal Minister for the Environment, Nature Conservation and Nuclear Safety, p. 5ff.
↑ Decision of the Commission of December 18, 2006 on the non-inclusion of alachlor in Annex I of Directive 91/414 / EEC ... (PDF)
↑ General Directorate Health and Food Safety of the European Commission: Entry on alachlor in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on March 11, 2016.
↑ R. Loos, S. Tavazzi, B. Paracchini, E. Canuti, C. Weissteiner: Analysis of polar organic contaminants in surface water of the northern Adriatic Sea by solid-phase extraction Followed by ultra high-pressure liquid chromatography-MS QTRAP® using a hybrid triple-quadrupole linear ion trap instrument. In: Anal Bioanal Chem. 405 (18), Jul 2013, pp. 5875-5885. PMID 23657443 .
↑ E. Terzopoulou, D. Voutsa, G. Kaklamanos: A multi-residue method for determination of 70 organic micropollutants in surface waters by solid-phase extraction followed by gas chromatography coupled to tandem mass spectrometry. In: Environ Sci Pollut Res Int. 22 (2), Jan 2015, pp. 1095-1112. PMID 25109470 .

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Entry on alachlor in the GESTIS substance database of the IFA , accessed on January 8, 2020(JavaScript required) .

[inchem-2] WHO / FAO Data Sheet on Pesticides (PDS) for Alachlor , accessed December 9, 2014.

[CLP_100.036.448-3] Entry on alachlor 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] Pesticide Reregistration Sheet (English) ( Memento from December 9, 1999 in the Internet Archive ) (PDF; 45 kB).

[umwelt-5] Emission reduction for priority and priority hazardous substances of the Water Framework Directive - Material data sheets - Data sheet Alachlor . Texts 29/07, Environmental Research Plan of the Federal Minister for the Environment, Nature Conservation and Nuclear Safety, p. 5ff.

[6] Decision of the Commission of December 18, 2006 on the non-inclusion of alachlor in Annex I of Directive 91/414 / EEC ... (PDF)

[PSM-7] General Directorate Health and Food Safety of the European Commission: Entry on alachlor in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on March 11, 2016.

[8] R. Loos, S. Tavazzi, B. Paracchini, E. Canuti, C. Weissteiner: Analysis of polar organic contaminants in surface water of the northern Adriatic Sea by solid-phase extraction Followed by ultra high-pressure liquid chromatography-MS QTRAP® using a hybrid triple-quadrupole linear ion trap instrument. In: Anal Bioanal Chem. 405 (18), Jul 2013, pp. 5875-5885. PMID 23657443 .

[9] E. Terzopoulou, D. Voutsa, G. Kaklamanos: A multi-residue method for determination of 70 organic micropollutants in surface waters by solid-phase extraction followed by gas chromatography coupled to tandem mass spectrometry. In: Environ Sci Pollut Res Int. 22 (2), Jan 2015, pp. 1095-1112. PMID 25109470 .