S-metolachlor (Ref: CGA 77102) |
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GENERAL INFORMATION
for S-metolachlor
Description: Isomer herbicide mixture used to control grasses and some broad-leaved weeds in a wide range of crops
Example pests controlled: Nightshade; Crabgrass; Pigweed; Foxtail; Yellow nutsedge; Witchgrass
Example applications: Corn; Soybeans; Beans & peas; Potatoes; Sugarbeet; Lupin; Sunflower; Fruit trees
Efficacy & activity: Efficacy demonstrated by extensive use and field trials
Availability status: Current
Introduction & key dates: circa 1998
EC Regulation 1107/2009 (repealing 91/414):
Status | Approved |
Dossier rapporteur/co-rapporteur | Germany/France |
Date inclusion expires | 31/07/2020 |
EU Candidate for substitution (CfS) | No |
Listed in EU database | Yes |
Approved for use () or known to be used (
) in the following European countries:
AT |
BE |
BG |
CY |
CZ |
DE |
DK |
EE |
EL |
ES |
FI |
FR |
HR |
HU |
IE |
IT |
LT |
LU |
LV |
MT |
NL |
PL |
PT |
RO |
SE |
SI |
SK |
UK |
Also used in: Australia
Isomerism | Metolachlor exisits as the S- and R- entantiomers. S-metolachlor is a mixture of the S- and R-formats in an approximate ratio 88:12 . |
Chemical formula | C15H22ClNO2 |
Canonical SMILES | C1=CC(=CC=C1CSC(=NC2=C(C=C(C=C2)Cl)Cl)CN3C=NC=N3)Cl |
Isomeric SMILES | No data |
International Chemical Identifier key (InChIKey) | WVQBLGZPHOPPFO-LBPRGKRZSA-N |
International Chemical Identifier (InChI) | InChI=1S/C15H22ClNO2/c1-5-13-8-6-7-11(2)15(13)17(14(18)9-16)12(3)10-19-4/h6-8,12H,5,9-10H2,1-4H3/t12-/m0/s1 |
2D structure diagram/image available? | Yes |
Pesticide type | Herbicide | |
Substance group | Chloroacetamide | |
Minimum active substance purity | 960 g/kg | |
Known relevant impurities | EU dossier - None declared | |
Substance origin | Synthetic | |
Mode of action | Selective, absorbed through roots and shoots. Inhibition of VLCFA (inhibition of cell division). | |
CAS RN | 87392-12-9 | |
Alternative/old CAS RN | 178961-20-1 | |
EC number | 257-060-8 | |
CIPAC number | 607 | |
US EPA chemical code | 108800 | |
PubChem CID | 11140605 | |
Molecular mass (g mol-1) | 283.79 | |
PIN (Preferred Identification Name) | mixture of 80–100% 2-chloro-N-(2-ethyl-6-methylphenyl)-N-[(2S)-1-methoxypropan-2-yl]acetamide and 20–0% 2-chloro-N-(2-ethyl-6-methylphenyl)-N-[(2R)-1-methoxypropan-2-yl]acetamide | |
IUPAC name | mix of: (aRS,1S)-2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)acet-o-toluidide and 20–0% (aRS,1R)-2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)acet-o-toluidide | |
CAS name | 2-chloro-N-(2-ethyl-6-methylphenyl)-N-((1S)-2-methoxy-1-methylethyl)acetamide | |
Other status information | Possible groundwater contaminant | |
Relevant Environmental Water Quality Standards | - | |
Herbicide Resistance Classification (HRAC) | K3 | |
Herbicide Resistance Classification (WSSA) | 15 | |
Insecticide Resistance Classification (IRAC) | Not applicable | |
Fungicide Resistance Classification (FRAC) | Not applicable | |
Examples of recorded resistance | - | |
Physical state | Clear straw-coloured liquid | |
Related substances & organisms |
Formulations:
ENVIRONMENTAL FATE
for S-metolachlor
Key metabolites:
Metabolite | Formation medium | Estimated maximum occurrence fraction | 1107/2009 relevancy ![]() |
|
metolachlor oxanilic acid (Ref: CGA 51202) ![]() |
Soil | 0.211 | Major fraction, Relevant | |
metolachlor ethane sulfonic acid (Ref: CGA 354743) ![]() |
Soil | 0.213 | Major fraction, Relevant | |
2-((2-Ethyl-6-methyl-phenyl)-oxalylamino)-propionic acid (Ref: CGA 357704) ![]() |
Soil | 0.219 | Major fraction, Relevant |
ECOTOXICOLOGY
for S-metolachlor
HUMAN HEALTH AND PROTECTION
for S-metolachlor
General:
Property ![]() |
Value | Source/Quality Score/Other Information ![]() |
Interpretation ![]() |
|
Threshold of Toxicological Concern (Cramer Class) ![]() |
High (class III) | - | - | |
Mammals - Acute oral LD50 (mg kg-1) | > 2000 | A5 Rat | Low | |
Mammals - Dermal LD50 (mg kg-1 body weight) | > 2000 | A5 Rat | - | |
Mammals - Inhalation LC50 (mg l-1) | > 2.91 | A5 Rat 4hr (nose only) | - | |
Other Mammal toxicity endpoints | - | - | ||
ADI - Acceptable Daily Intake (mg kg-1bw day-1) | 0.1 | A5 Dog, SF=100 | - | |
ARfD - Acute Reference Dose (mg kg-1bw day-1) | 0.5 | A5 Rat, SF=100 | - | |
AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) | None allocated | A5 | - | |
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) | 0.1 | A5 Dog, SF=100 | - | |
Dermal penetration studies (%) | 0.4-13% | A5 concentration dependent | - | |
Dangerous Substances Directive 76/464 | - | - | - | |
Exposure Routes | Public | Main risk for bystanders and residents arises from spray drift | ||
Occupational | Acceptable levels with PPE/PPC | |||
European MRLs | Click here for the EU MRL pesticide database | |||
Drinking Water Standards | - | - | - | |
Drinking Water MAC (μg l-1) | - | - | - |
Health issues:
Carcinogen | Genotoxic | Endocrine disrupter | Reproduction / development effects | Cholinesterase inhibitor | Neurotoxicant | |||
A0; B0; C0; D0; E0 | - |
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Respiratory tract irritant | Skin irritant | Skin sensitiser | Eye irritant | Phototoxicant | ||||
|
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General human health issues | Possible liver and thyroid toxicant USEPA - possible human carcinogen |
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Key: Genotoxicity A: Chromosome aberration (EFSA database) B: DNA damage/repair (EFSA database) C: Gene mutation (EFSA database) D: Genome mutation (EFSA database) E: Unspecified genotoxicity type (miscellaneous data source) 0: No data 1: Positive 2: Mixed/ambiguous results 3: Negative |
Key: Other![]() ![]() ![]() - : No data found |
Handling issues:
TRANSLATIONS
for S-metolachlor
Language | Name |
English | S-metolachlor |
French | S-metolachlore |
German | S-Metolachlor |
Danish | S-metolachlor |
Italian | S-metolaclor |
Spanish | S-metolachloro |
Greek | S-metolachlor |
Slovenian | S-metolaklor |
Polish | S-metolachlor |
Swedish | - |
Hungarian | S-metolachlor |
Dutch | S-metolachloor |
Record last updated: Wednesday 27 November 2019
Contact: aeru@herts.ac.uk