| oxydemeton-methyl (Ref: ENT 24964) |
 |
Environmental Fate - Ecotoxicology - Human Health - A to Z Index - Home
GENERAL INFORMATION 
for oxydemeton-methyl
Description: An insecticide and acaricide for the control of insect pests in both food and non-food situations
Example pests controlled: Aphids including the green peach aphid, mustard aphid; Mites; Thrips; Sawflies
Example applications: Vegetables; Fruit; Field crops; Ornamental shrubs and trees
Efficacy & activity: -
Availability status: Current
Introduction & key dates: -
EC Regulation 1107/2009 (repealing 91/414):
| Status | Not approved |
| Dossier rapporteur/co-rapporteur | France |
| Date inclusion expires | Expired |
| EU Candidate for substitution (CfS) | Not applicable |
| 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 |
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Chemical structure:
| Isomerism | A molecule with one chiral centre |
| Chemical formula | C6H15O4PS2 |
| Canonical SMILES | CCS(=O)CCSP(=O)(OC)OC |
| Isomeric SMILES | No data |
| International Chemical Identifier key (InChIKey) | PMCVMORKVPSKHZ-UHFFFAOYSA-N |
| International Chemical Identifier (InChI) | InChI=1S/C6H15O4PS2/c1-4-13(8)6-5-12-11(7,9-2)10-3/h4-6H2,1-3H3 |
| 2D structure diagram/image available? | Yes |
General status:
| Pesticide type | Insecticide | |
| Substance group | Organophosphate | |
| Minimum active substance purity | 95% | |
| Known relevant impurities | EU dossier - demeton-S-methyl <=3.5% and demeton-S-methyl sulfone <=2% | |
| Substance origin | Synthetic | |
| Mode of action | Systemic with contact and stomach action. Rapid knockdown effect. Cholinesterase inhibitor. | |
| CAS RN | 301-12-2 | |
| EC number | 206-110-7 | |
| CIPAC number | 171 | |
| US EPA chemical code | 058702 | |
| PubChem CID | 4618 | |
| Molecular mass (g mol-1) | 246.3 | |
| PIN (Preferred Identification Name) | - | |
| IUPAC name | S-2-ethylsulfinylethyl O,O-dimethyl phosphorothioate | |
| CAS name | S-(2-(ethylsulfinyl)ethyl) O,O-dimethyl phosphorothioate | |
| Other status information | Potential groundwater contaminant; Chemical subject to PIC regulations | |
| Relevant Environmental Water Quality Standards | - | |
| Herbicide Resistance Classification (HRAC) | Not applicable | |
| Herbicide Resistance Classification (WSSA) | Not applicable | |
| Insecticide Resistance Classification (IRAC) | 1B | |
| Fungicide Resistance Classification (FRAC) | Not applicable | |
| Examples of recorded resistance | Aphis gossypii Myzocallis coryli Myzus persicae |
|
| Physical state | Colourless liquid | |
| Related substances & organisms | ||
Formulations:
| Property |
Value | |||
| Example manufacturers & suppliers of products using this active now or historically |
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| Example products using this active |
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| UK LERAP status | No UK approval for use as a pesticide under EC Regulation 1107/2009 | |||
| Formulation and application details | Usually supplied as an emsulsifiable concentrate. | |||
ENVIRONMENTAL FATE
for oxydemeton-methyl
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Solubility - In water at 20oC (mg l-1) | 1200000 | A5 | High | |
| Solubility - In organic solvents at 20oC (mg l-1) | 25 | A5 - n-Hexane | - | |
| 250000 | A5 - Toluene | - | ||
| 250000 | A5 - 1-Octanol | - | ||
| 250000 | A5 - Acetone | - | ||
| Melting point (oC) | -49 | A5 | - | |
| Boiling point (oC) | Decomposes before boiling | A5 | - | |
| Degradation point (oC) | 65 | A5 | - | |
| Flashpoint (oC) | 80.5 | A5 | - | |
| Octanol-water partition coefficient at pH 7, 20oC | P | 1.82 X 10-01 | Calculated | - |
| Log P | -0.74 | A5 | Low | |
| Bulk density (g ml-1)/Specific gravity | 1.31 | A5 | - | |
| Dissociation constant (pKa) at 25oC | Not applicable | A5 | - | |
| Note: Not determinable | ||||
| Vapour pressure at 20oC (mPa) | 2 | A5 | Low volatility | |
| Henry's law constant at 25oC (Pa m3 mol-1) | 4.00 X 10-07 | A5 | Non-volatile | |
GUS leaching potential index  |
0.00 | Calculated | Low leachability | |
| SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate |
Value | 9.61 X 10-04 | Calculated | - |
| Note | - | |||
| Potential for particle bound transport index |
- | Calculated | Low | |
| Maximum UV-vis absorption L mol-1 cm-1 | Maxima at 213nm = 1356 | A5 | - | |
| Surface tension (mN m-1) | 66.0 | A5 | - | |
Degradation:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
General biodegradability | - |
| Soil degradation (days) (aerobic) | DT50 (typical) | 1 | K4 | Non-persistent |
| DT50 (lab at 20oC) | 1 | A5 | Non-persistent | |
| DT50 (field) | 5 | A5 | Non-persistent | |
| DT90 (lab at 20oC) | 3.32 | A5 | - | |
| DT90 (field) | 2.66 | A5 | - | |
| DT50 modelling endpoint | - | - | - | |
| Note | EU dossier Lab studies DT50 range 0.4-3.2 days, DT90 range 1.3-10.6 days at 25DegC; Field studies DT50 raneg 1.49-3.82 days, DT90 range 4.9-12.7 days | |||
| Dissipation rate RL50 on plant matrix | Value | - | - | - |
| Note | - | |||
| Dissipation rate RL50 on and in plant matrix | Value | 3.6 | R4 | - |
| Note | Published literature RL50 range 3.1-4.0 days, 2 field crops, various matrices, n=2 | |||
| Aqueous photolysis DT50 (days) at pH 7 | Value | 222 | A5 | Stable |
| Note | Not significant route of degradation. DT50 187 days daylight, 257 days in dark, pH 5, 38 deg N, Spring | |||
| Aqueous hydrolysis DT50 (days) at 20oC and pH 7 | Value | 73 | A5 | Moderately persistent |
| Note | pH sensitive: DT50 96.3 days at pH 5, 41 days at pH 7, 2.4 days at pH 4, all at 25 degC. 73 days at pH 7 and 20 degC | |||
| Water-sediment DT50 (days) | 3 | A5 | Fast | |
| Water phase only DT50 (days) | 3 | A5 | Moderately fast | |
Soil adsorption and mobility:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Linear | Kd | - | DW4 | Very mobile |
| Koc | 10 | |||
| Notes and range | - | |||
| Freundlich | Kf | 0.36 | A5 | Mobile |
| Kfoc | 29 | |||
| 1/n | 0.928 | |||
| Notes and range | EU dossier Kf range 0.01-0.89 mL/g, kfoc range 2-58 mL/g, 1/n range 0.83-1.14, Soils=4 | |||
| pH sensitivity | No | |||
Key metabolites:
| Metabolite | Formation medium | Estimated maximum occurrence fraction | 1107/2009 relevancy |
|
| 2-ethylsulfinyl ethane sulfonic acid |
Soil | 0.390 | Major fraction, Relevant | |
| 2-ethylsulfonyl ethane sulfonic acid |
Soil | 0.265 | Major fraction, Relevant | |
Other known metabolites:
| Metabolite name and reference | Aliases | Formation medium / Rate | Estimated maximum occurrence fraction | Metabolising enzymes |
| S-[2(ethylsulfonyl)ethyl]O,O-dimethylphoshorothioate | demeton-S-methylsulphon; oxydemeton-methyl metabolite M01 | Plant; Soil (Aerobic); Water/sediment | - | - |
| O-methyl-S-[2(ethylsulfinyl)ethyl] phoshorothioate | oxydemeton-methyl metabolite M06 | Plant; Water/sediment | - | - |
| O-methyl-S-[2(ethylsulfonyl)ethyl] phoshorothioate | oxydemeton-methyl metabolite M07 | Plant; Water/sediment | - | - |
| 1-(ethylsulfonyl)-2-(methylsulfonyl) ethane | oxydemeton-methyl metabolite M05 | Soil (Aerobic) | - | - |
| dimethyl phosphate | DMP | Soil (Aerobic); Water | - | - |
| S-[2(ethylthio)ethyl]O,O-dimethylphoshorothioate. Pesticide common name: demeton-S-methyl | oxydemeton-methyl metabolite M02 | Water/sediment | - | - |
| 2-ethylthio ethane sulfonic acid | oxydemeton-methyl metabolite M22 | Soil (Anaerobic) | - | - |
| bis-2-[(ethylsulfinyl)-ethyl]disulfide | oxydemeton-methyl metabolite M11 | Water/sediment | - | - |
| 2-ethylsulfinyl-ethyl mercaptan | oxydemeton-methyl metabolite M21 | Water/sediment | - | - |
ECOTOXICOLOGY
for oxydemeton-methyl
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Bio-concentration factor | BCF (l kg-1) | Low risk | A5 Based on LogP < 3 | Low potential |
| CT50 (days) | - | - | ||
| Mammals - Acute oral LD50 (mg kg-1) | 48 | A5 Rat | High | |
| Mammals - Short term dietary NOEL | (mg kg-1) | 0.1 | A4 Dog, 1 year | High |
| (ppm diet) | - | - | ||
| Birds - Acute LD50 (mg kg-1) | 34 | A5 Colinus virginianus | High | |
| Birds - Short term dietary (LC50/LD50) | 361 mg kg bw-1 day-1 | A5 Colinus virginianus | - | |
| Fish - Acute 96 hour LC50 (mg l-1) | 17 | A5 Oncorhynchus mykiss | Moderate | |
| Fish - Chronic 21 day NOEC (mg l-1) | 1.8 | A5 Oncorhynchus mykiss | Moderate | |
| Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) | 0.11 | A5 Daphnia magna | Moderate | |
| Aquatic invertebrates - Chronic 21 day NOEC (mg l-1) | 0.027 | A5 Daphnia magna | Moderate | |
| Aquatic crustaceans - Acute 96 hour LC50 (mg l-1) | - | - | - | |
| Sediment dwelling organisms - Acute 96 hour LC50 (mg l-1) | 0.011 | A4 Chironomus riparius, 48 hour | High | |
| Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l-1) | - | - | - | |
| Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg-1) | - | - | - | |
| Aquatic plants - Acute 7 day EC50, biomass (mg l-1) | - | - | - | |
| Non-target plants | - | - | - | |
| - | - | - | ||
| Algae - Acute 72 hour EC50, growth (mg l-1) | > 100 | A5 Scenedemus subspicatus | Low | |
| Algae - Chronic 96 hour NOEC, growth (mg l-1) | - | - | - | |
| Honeybees | Contact acute 48 hour LD50 (μg bee-1) | 0.175 | A5 | High |
| Oral acute 48 hour LD50 (μg bee-1) | 0.2 | A5 | High | |
| Unknown mode acute 48 hour LD50 (μg bee-1) | - | - | - | |
| Earthworms - Acute 14 day LC50 (mg kg-1) | 115 | A5 Eisenia foetida | Moderate | |
| Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1) | 0.41 | A4 Eisenia foetida | Moderate | |
| Other soil macro-organisms - e.g. Collembola | LR50 / EC50 / NOEC / % Effect | - | - | - |
| Other arthropod (1) | LR50 g ha-1 | 0.375 | >, 48 hour A5 Aphidius rhopalosiphi |
- |
| % Effect | - | - | - | |
| Other arthropod (2) | LR50 g ha-1 | 11.0 | 7 day A5 Typhlodromus pyri |
- |
| % Effect | - | - | - | |
| Soil micro-organisms | Nitrogen mineralisation: No significant adverse effect [Dose: 5 kg ha-1] Carbon mineralisation: No significant adverse effect [Dose: 6 kg ha-1] |
A5 | - | |
| Mesocosm study data | NOEAEC mg l-1 | - | - | - |
| NOEAEC mg l-1 | - | - | - | |
HUMAN HEALTH AND PROTECTION
for oxydemeton-methyl
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) | 48 | A5 Rat | High | |
| Mammals - Dermal LD50 (mg kg-1 body weight) | 112 | A5 Rat | - | |
| Mammals - Inhalation LC50 (mg l-1) | 0.471 | A5 Rat | - | |
| Other Mammal toxicity endpoints | - | - | ||
| ADI - Acceptable Daily Intake (mg kg-1bw day-1) | 0.0003 | A5 Rat, SF=100 | - | |
| ARfD - Acute Reference Dose (mg kg-1bw day-1) | 0.0015 | A5 Rat, SF=100 | - | |
| AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) | - | - | - | |
| AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) | 0.001 | A5 Rat, SF=100 | - | |
| Dermal penetration studies (%) | 20.0 | A5 | - | |
| Dangerous Substances Directive 76/464 | List II | - | - | |
| Exposure Limits | - | - | - | |
| Exposure Routes | Public | Possible risk to bystanders | ||
| Occupational | Possible exposure risk during treatment of orchards | |||
| European MRLs | Click here for the EU MRL pesticide database | |||
| Drinking Water Standards | - | - | - | |
| Drinking Water MAC (μg l-1) | - | - | - | |
Health issues:
| Carcinogen | Mutagen | Endocrine disrupter | Reproduction / development effects | Cholinesterase inhibitor | Neurotoxicant | |||
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| Respiratory tract irritant | Skin irritant | Skin sensitiser | Eye irritant | Phototoxicant | ||||
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| General human health issues | Highly toxic | |||||||
: Yes, known to cause a problem
: No, known not to cause a problem
: Possibly, status not identified
- : No data found
Handling issues:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| General |
Not explosive IMDG Transport Code is usually 6.1 |
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| CLP classification 2013 | Health: H301, H311 Environment: H400 |
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| EC Risk Classification |
T - Toxic: R24/25 N - Dangerous for the environment: R50 |
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| EC Safety Classification |
S1/2, S23, S36/37, S45, S61 | |||
| WHO Classification | Ib | - | Highly hazardous | |
| US EPA Classification (formulation) | No consensus across products or no products available | - | - | |
| UN Number | 3018 | |||
| Waste disposal & packaging |
Packaging Group II (medium danger) | |||
TRANSLATIONS
for oxydemeton-methyl
| Language | Name |
| English | oxydemeton-methyl |
| French | oxydemeton-methyle |
| German | Oxydemeton-methyl |
| Danish | oxydemeton-methyl |
| Italian | ossidemeton-metil |
| Spanish | oxidemeton metil |
| Greek | oxydemeton-methyl |
| Slovenian | oksidemeton metil |
| Polish | oksydemeton metylu |
| Swedish | - |
| Hungarian | oxidemeton-methyl |
| Dutch | oxydemeton-methyl |
Record last updated: Friday 24 August 2018
Contact: aeru@herts.ac.uk