| pethoxamid (Ref: ASU 96 520H) |
 |
Environmental Fate - Ecotoxicology - Human Health - A to Z Index - Home
GENERAL INFORMATION 
for pethoxamid
Description: A pre-emergence and early post-emergence herbicide to control some grass and broad-leaved weeds
Example pests controlled: Foxtail; Crabgrass; Barnyardgass; Ladysthumb; Bindweed; Pigweed; Common lambsquarter
Example applications: Corn; Winter OSR; Soybeans; Peas and beans; Tobacco
Efficacy & activity: Substances has been evaulated via field trials and has been in usefor many years
Availability status: Current
Introduction & key dates: 2002
EC Regulation 1107/2009 (repealing 91/414):
| Status | Approved |
| Dossier rapporteur/co-rapporteur | Austria/Czech Republic |
| Date inclusion expires | 30/11/2033 |
| 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 |
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Chemical structure:
| Isomerism | - |
| Chemical formula | C16H22ClNO2 |
| Canonical SMILES | CCOCCN(C(=O)CCl)C(=C(C)C)C1=CC=CC=C1 |
| Isomeric SMILES | No data |
| International Chemical Identifier key (InChIKey) | CSWIKHNSBZVWNQ-UHFFFAOYSA-N |
| International Chemical Identifier (InChI) | InChI=1S/C16H22ClNO2/c1-4-20-11-10-18(15(19)12-17)16(13(2)3)14-8-6-5-7-9-14/h5-9H,4,10-12H2,1-3H3 |
| 2D structure diagram/image available? | Yes |
General status:
| Pesticide type | Herbicide | |||
| Substance group | Chloroacetamide | |||
| Minimum active substance purity | 945 g/kg | |||
| Known relevant impurities | EU dossier - Toluene <3.0 g/kg | |||
| Substance origin | Synthetic | |||
| Mode of action | Systemic, absorbed by roots and young shoots. Inhibition of VLCFA (inhibition of cell division). | |||
| CAS RN | 106700-29-2 | |||
| EC number | - | |||
| CIPAC number | 665 | |||
| US EPA chemical code | - | |||
| PubChem CID | 6450826 | |||
| Molecular mass (g mol-1) | 295.81 | |||
| PIN (Preferred Identification Name) | 2-chloro-N-(2-ethoxyethyl)-N-(2-methyl-1-phenylprop-1-en-1-yl)acetamide | |||
| IUPAC name | 2-chloro-N-(2-ethoxyethyl)-N-(2-methyl-1-phenylprop-1-enyl)acetamide | |||
| CAS name | 2-chloro-N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)acetamide | |||
| Other status information | - | |||
| 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 | Off-white crystalline solid | |||
| Related substances & organisms | - | |||
Formulations:
| Property |
Value | |||
| Example manufacturers & suppliers of products using this active now or historically | - | |||
| Example products using this active |
|
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| UK LERAP status | Yes - see label | |||
| Formulation and application details | Usually formulated as an emulsifiable concentrate for use as a foliar spray. | |||
ENVIRONMENTAL FATE
for pethoxamid
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Solubility - In water at 20oC (mg l-1) | 400 | A5 | Moderate | |
| Solubility - In organic solvents at 20oC (mg l-1) | 117000 | A5 - n-Heptane | - | |
| 250000 | A5 - n-Hexane | - | ||
| 250000 | A5 - Methanol | - | ||
| 250000 | A5 - Ethyl acetate | - | ||
| Melting point (oC) | 37.5 | A5 | - | |
| Boiling point (oC) | Decomposes before boiling | A5 | - | |
| Degradation point (oC) | 200 | A5 | - | |
| Flashpoint (oC) | 299 | A5 - Auto-flammability | - | |
| Octanol-water partition coefficient at pH 7, 20oC | P | 9.12 X 1002 | Calculated | - |
| Log P | 2.96 | A5 - @ pH 5 | Moderate | |
| Bulk density (g ml-1)/Specific gravity | 1.19 | A5 | - | |
| Dissociation constant (pKa) at 25oC | Not applicable | A5 | - | |
| Note: No dissociation | ||||
| Vapour pressure at 20oC (mPa) | 2.8 | A5 | Low volatility | |
| Henry's law constant at 25oC (Pa m3 mol-1) | 1.18 X 10-03 | A5 | Non-volatile | |
GUS leaching potential index  |
1.34 | Calculated | Low leachability | |
| SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate |
Value | 6.69 X 10-03 | Calculated | - |
| Note | - | |||
| Potential for particle bound transport index |
- | Calculated | Low | |
| Maximum UV-vis absorption L mol-1 cm-1 | Acidic: 242nm=12100, Neutral: 243nm=12200, Basic: 243nm=12200 | A5 | - | |
| Surface tension (mN m-1) | 53.0 | A5 | - | |
Degradation:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
General biodegradability | Not readily biodegradeable |
| Soil degradation (days) (aerobic) | DT50 (typical) | 6.3 | A5 | Non-persistent |
| DT50 (lab at 20oC) | 6.3 | A5 | Non-persistent | |
| DT50 (field) | 14.8 | A5 | Non-persistent | |
| DT90 (lab at 20oC) | 20.9 | A5 | - | |
| DT90 (field) | 84.9 | A5 | - | |
| DT50 modelling endpoint | - | - | - | |
| Note | EU 2016 RAR dossier lab studies DT50 range 5.5-8.1 days, DT90 range 18.2-27.0 days, Soils=4; Field studies range 7.3-22.2 days, DT90 range 73.7-96.0 days, Soils=2 | |||
| Dissipation rate RL50 on plant matrix | Value | - | - | - |
| Note | - | |||
| Dissipation rate RL50 on and in plant matrix | Value | - | - | - |
| Note | - | |||
| Aqueous photolysis DT50 (days) at pH 7 | Value | 14 | A5 | Slow |
| Note | DT50 49 days, natural sunlight, 40 deg N, 12 hrs daylight. | |||
| Aqueous hydrolysis DT50 (days) at 20oC and pH 7 | Value | Stable | A5 | - |
| Note | Stable pH 4 to pH 9 | |||
| Water-sediment DT50 (days) | 9.5 | A5 | Fast | |
| Water phase only DT50 (days) | 8.0 | A5 | Moderately fast | |
Soil adsorption and mobility:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Linear | Kd | - | A5 Worse case field value | - |
| Koc | - | |||
| Notes and range | 22.2 | |||
| Freundlich | Kf | 4.4 | A5 | Moderately mobile |
| Kfoc | 211 | |||
| 1/n | 0.89 | |||
| Notes and range | EU 2016 RAR dossier Kf range 1.12-9.15 mL/g, Kfoc range 187-241 mL/g, No 1/n range 0.87-0.91, Soils=4 | |||
| pH sensitivity | No | |||
Key metabolites:
| Metabolite | Formation medium | Estimated maximum occurrence fraction | 1107/2009 relevancy |
|
| N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)-2-sulfoacetamide |
Soil | 0.112 | Major fraction, Relevant | |
| N-(2-ethoxyethyl)-N-((1Z)-3-hydroxy-2-methyl-1-phenylprop-1-en-1-yl)-2-sulfanylacetamide | Soil | 0.009 | Minor fraction, relevant | |
| 2-(N-(2-Methyl-1-phenylprop-1-en-1-yl)-2-sulfoacetamido)acetic acid | Soil | 0.009 | Minor fraction, relevant | |
Other known metabolites:
| Metabolite name and reference | Aliases | Formation medium / Rate | Estimated maximum occurrence fraction | Metabolising enzymes |
| 3-[N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)-carbamoylmethylthio]-D,L-lactic acid | pethoxamid metabolite MET-41; TKC-94-S-lactic acid | Plant | - | - |
| 3-[N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)-carbamoylmethylsulfinyl]-D,L lactic acid | pethoxamid metabolite MET-50; TKC-94-SO-lactic acid | Plant | - | - |
| 3-N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)-carbamoyl-methylthio]-2-(1-alpha-D-glucopyranosyloxy)propionic acid | pethoxamid metabolite MET-58; TKC-94-S-lactic glucoside | Plant | - | - |
| S-[N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)-carbamoyl-methyl]-D,L-cystein | pethoxamid metabolite MET-30; TKC-94 cystein | Plant | - | - |
| N-(2-amino-4-carboxybutanoic-4-yl)-S-[N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)-carbamoyl-methyl]-D,L-cystein | TKC-94-g-glutamyl cystein | Plant | - | - |
| N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)-2-(2-aminopropion-3-yl)sulfinylacetamide | pethoxamid metabolite MET-49; TKC-94-SO-cystein | Plant | - | - |
| N-(2-carboxyacetyl)-S-[N-(2-ethoxyethyl)-N-(2-methyl-1-phenyl-1-propenyl)carbamoyl-methyl]-D,L-cystein | pethoxamid metabolite MET-47; TKC-94-N-malonyl cystein | Plant | - | - |
| N-(2-ethoxyethyl)-2-sulfinyl-N-(2-methyl-1-phenyl-1-propenyl)-acetamide | TKC-94-thiol | Plant | - | - |
| N-(2-ethoxyethyl)-2-mercapto-N-(2-methyl-1-phenyl-1-propenyl)-acetamide | pethoxamid metabolite MET-43; TKC-94-thiol | Plant | - | - |
| 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) | 983 | A5 Rat | Moderate | |
| Mammals - Short term dietary NOEL | (mg kg-1) | 1 | A5 Rat, 2 year | High |
| (ppm diet) | 25 | - | ||
| Birds - Acute LD50 (mg kg-1) | 1578 | A5 Colinus virginianus | Moderate | |
| Birds - Short term dietary (LC50/LD50) | 1200 mg kg bw-1 day-1 | A5 Colinus virginianus | - | |
| Fish - Acute 96 hour LC50 (mg l-1) | 2.2 | A5 Oncorhynchus mykiss | Moderate | |
| Fish - Chronic 21 day NOEC (mg l-1) | 1.1 | A5 Oncorhynchus mykiss, 28 day | Moderate | |
| Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) | 23 | A5 Daphnia magna | Moderate | |
| Aquatic invertebrates - Chronic 21 day NOEC (mg l-1) | 2.8 | A5 Daphnia magna | Moderate | |
| Aquatic crustaceans - Acute 96 hour LC50 (mg l-1) | - | - | - | |
| Sediment dwelling organisms - Acute 96 hour LC50 (mg l-1) | - | - | - | |
| 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) | 0.0247 | A5 Lemna gibba | Moderate | |
| Non-target plants | 0.425 | A5 Lolium perenne Vegetative vigour, ER50 As g product/ha |
- | |
| 0.592 | A5 Lolium perenne Seedling emergence, ER50 As g product/ha |
- | ||
| Algae - Acute 72 hour EC50, growth (mg l-1) | > 149 | A5 Pseudokirchneriella subcapitata | Low | |
| Algae - Chronic 96 hour NOEC, growth (mg l-1) | - | - | - | |
| Honeybees | Contact acute 48 hour LD50 (μg bee-1) | > 200 | A5 Apis mellifera | Low |
| Oral acute 48 hour LD50 (μg bee-1) | > 200 | A5 Apis mellifera | Low | |
| Unknown mode acute 48 hour LD50 (μg bee-1) | - | - | - | |
| Earthworms - Acute 14 day LC50 (mg kg-1) | 316 | A5 Eisenia foetida | Moderate | |
| Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1) | 8.0 | A5 Eisenia foetida | Moderate | |
| Other soil macro-organisms - e.g. Collembola | LR50 / EC50 / NOEC / % Effect | - | - | - |
| Other arthropod (1) | LR50 g ha-1 | - | - | - |
| % Effect | 100 | Mortality Dose: 1.2 kg/ka A5 Aphidius rhopalosiphi, imagine |
- | |
| Other arthropod (2) | LR50 g ha-1 | - | - | - |
| % Effect | 100 | Mortality Dose: 1.2 kg ha-1 A5 Typhlodromus pyri, protonymph |
- | |
| Soil micro-organisms | Nitrogen mineralisation: No significant adverse effect Carbon mineralisation: No significant adverse effect |
A5 Dose: 12 kg ha-1 |
- | |
| Mesocosm study data | NOEAEC mg l-1 | - | - | - |
| NOEAEC mg l-1 | - | - | - | |
HUMAN HEALTH AND PROTECTION
for pethoxamid
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) | 983 | A5 Rat | Moderate | |
| Mammals - Dermal LD50 (mg kg-1 body weight) | > 2000 | A5 Rat | - | |
| Mammals - Inhalation LC50 (mg l-1) | > 4.16 | A5 Rat, 4 hr (whole body) | - | |
| Other Mammal toxicity endpoints | - | - | ||
| ADI - Acceptable Daily Intake (mg kg-1bw day-1) | 0.01 | A5 Rat, SF=100 | - | |
| ARfD - Acute Reference Dose (mg kg-1bw day-1) | 0.08 | A5 Rat, SF=100 | - | |
| AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) | 0.08 | A5 Rat, SF=100 | - | |
| AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) | 0.02 | A5 Dog, 1 year, SF=100 | - | |
| Dermal penetration studies (%) | 2-8 | A5 concentration dependent | - | |
| Dangerous Substances Directive 76/464 | - | - | - | |
| Exposure Limits | - | - | - | |
| Exposure Routes | Public | Minimal risk from dietary exposure Risk assessment indicates ARfD would not normally be execeeded |
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| Occupational | Risk of operator exposure where protective equipment is not used - PPE/PPC advised | |||
| 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 | Possible liver & thyroid toxicant | |||||||
: 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 or oxidising Auto-flammability @ 299 DegC |
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| CLP classification 2013 | Health: H302, H317 Environment: H400, H410 |
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| EC Risk Classification |
Xn - Harmful: R22, R43 N - Dangerous for the environment: R50, R53 |
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| EC Safety Classification |
S2, S24, S37, S46, S60, S61 | |||
| WHO Classification | NL | - | Not listed | |
| US EPA Classification (formulation) | No consensus acorss products or no products available | - | - | |
| UN Number | - | |||
| Waste disposal & packaging |
- | |||
| Language | Name |
| English | pethoxamid |
| French | - |
| German | Pethoxamid |
| Danish | pethoxamid |
| Italian | - |
| Spanish | - |
| Greek | - |
| Slovenian | petoksamid |
| Polish | petoksamid |
| Swedish | - |
| Hungarian | - |
| Dutch | - |
Record last updated: Tuesday 14 May 2019
Contact: aeru@herts.ac.uk