| chloroxuron (Ref: C 1983) |
 |
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GENERAL INFORMATION 
for chloroxuron
Description: An obsolete selective phenylurea herbicide once used to control annual grasses, mosses and broad-leaved weeds
Example pests controlled: Barnyardgrass; Nightshade; Carpetweed; Corn cockle; Dandelion; Goosegrass; Crabgrass; Ragweed; Puslane; Shepherd's purse; Pigweed; Velvetleaf
Example applications: Soybeans; Onions; Strawberries; Celery; Ornamentals; vegetables including onions, carrots, leeks, peas & beans
Efficacy & activity: -
Availability status: Obsolete
Introduction & key dates: 1961, first reported
EC Regulation 1107/2009 (repealing 91/414):
| Status | Not approved |
| Dossier rapporteur/co-rapporteur | Not applicable |
| Date inclusion expires | Expired |
| EU Candidate for substitution (CfS) | - |
| 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 | C15H15ClN2O2 |
| Canonical SMILES | CN(C)C(=O)NC1=CC=C(C=C1)OC2=CC=C(C=C2)Cl |
| Isomeric SMILES | No data |
| International Chemical Identifier key (InChIKey) | IVUXTESCPZUGJC-UHFFFAOYSA-N |
| International Chemical Identifier (InChI) | InChI=1S/C15H15ClN2O2/c1-18(2)15(19)17-12-5-9-14(10-6-12)20-13-7-3-11(16)4-8-13/h3-10H,1-2H3,(H,17,19) |
| 2D structure diagram/image available? | Yes |
General status:
| Pesticide type | Herbicide | |||
| Substance group | Dimethylurea | |||
| Minimum active substance purity | - | |||
| Known relevant impurities | - | |||
| Substance origin | Synthetic | |||
| Mode of action | Photosynthetic electron transport inhibitor at the photosystem II receptor. Growth inhibition and chlorotic and necrotic effects on foliage | |||
| CAS RN | 1982-47-4 | |||
| EC number | 217-843-7 | |||
| CIPAC number | 187 | |||
| US EPA chemical code | 025501 | |||
| PubChem CID | 16115 | |||
| Molecular mass (g mol-1) | 290.75 | |||
| PIN (Preferred Identification Name) | N'-[4-(4-chlorophenoxy)phenyl]-N,N-dimethylurea | |||
| IUPAC name | 3-[4-(4-chlorophenoxy)phenyl]-1,1-dimethylurea | |||
| CAS name | N'-[4-(4-chlorophenoxy)phenyl]-N,N-dimethylurea | |||
| Other status information | - | |||
| Relevant Environmental Water Quality Standards | - | |||
| Herbicide Resistance Classification (HRAC) | C2 | |||
| Herbicide Resistance Classification (WSSA) | 7 | |||
| Insecticide Resistance Classification (IRAC) | Not applicable | |||
| Fungicide Resistance Classification (FRAC) | Not applicable | |||
| Examples of recorded resistance | - | |||
| Physical state | Solid | |||
| 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 a wettable powder. | |||
ENVIRONMENTAL FATE
for chloroxuron
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Solubility - In water at 20oC (mg l-1) | 3.7 | K4 | Low | |
| Solubility - In organic solvents at 20oC (mg l-1) | 44000 | CA3 - Acetone | - | |
| 106000 | CA3 - Dichloromethane | - | ||
| 4000 | CA3 - Toluene | - | ||
| 35000 | CA3 - Toluene | - | ||
| Melting point (oC) | 151 | Q3 | - | |
| Boiling point (oC) | - | - | - | |
| Degradation point (oC) | - | - | - | |
| Flashpoint (oC) | - | - | - | |
| Octanol-water partition coefficient at pH 7, 20oC | P | 2.51 X 1003 | Calculated | - |
| Log P | 3.4 | K4 | High | |
| Bulk density (g ml-1)/Specific gravity | - | - | - | |
| Dissociation constant (pKa) at 25oC | - | - | - | |
| Note: | ||||
| Vapour pressure at 20oC (mPa) | 2.30 X 10-04 | K4 | Low volatility | |
| Henry's law constant at 25oC (Pa m3 mol-1) | 6.00 X 10-05 | H4 | Non-volatile | |
GUS leaching potential index  |
0.98 | Calculated | Low leachability | |
| SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate |
Value | 1.96 X 10-02 | Calculated | - |
| Note | - | |||
| Potential for particle bound transport index |
- | Calculated | Medium | |
| Maximum UV-vis absorption L mol-1 cm-1 | - | - | - | |
| Surface tension (mN m-1) | - | - | - | |
Degradation:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
General biodegradability | - |
| Soil degradation (days) (aerobic) | DT50 (typical) | 36 | K4 | Moderately persistent |
| DT50 (lab at 20oC) | - | - | - | |
| DT50 (field) | 60 | F3 | Moderately persistent | |
| DT90 (lab at 20oC) | - | - | - | |
| DT90 (field) | - | - | - | |
| DT50 modelling endpoint | - | - | - | |
| Note | Literature states DT50 typically ranges from 30 to 60 days, 110 days silt loam aerobic conditions (CA3) | |||
| 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 | 0.015 | K4 | Fast |
| Note | - | |||
| Aqueous hydrolysis DT50 (days) at 20oC and pH 7 | Value | 2896 | K4 | Very persistent |
| Note | - | |||
| Water-sediment DT50 (days) | - | - | - | |
| Water phase only DT50 (days) | 63 | K4 | Stable | |
Soil adsorption and mobility:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Linear | Kd | - | H3 | Slightly mobile |
| Koc | 2820 | |||
| Notes and range | Best available data | |||
| Freundlich | Kf | - | - | - |
| Kfoc | - | |||
| 1/n | - | |||
| Notes and range | - | |||
| pH sensitivity | - | |||
Key metabolites:
| Metabolite | Formation medium | Estimated maximum occurrence fraction | 1107/2009 relevancy |
|
| N-(4-chlorophenoxy)-phenyl-N-methylurea | Soil | - | Not assessed under 91/414 or 1107/2009 | |
| N-(4-chlorophenoxy)-phenylurea | Soil | - | Not assessed under 91/414 or 1107/2009 | |
| 4-chlorophenoxy-aniline | Soil | - | Not assessed under 91/414 or 1107/2009 | |
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Bio-concentration factor | BCF (l kg-1) | 105 | Q2 Estimated | Threshold for concern |
| CT50 (days) | Not available | - | ||
| Mammals - Acute oral LD50 (mg kg-1) | > 3700 | V3 Rat | Low | |
| Mammals - Short term dietary NOEL | (mg kg-1) | - | - | - |
| (ppm diet) | - | - | ||
| Birds - Acute LD50 (mg kg-1) | 2000 | F3 Anas platyrhynchos | Moderate | |
| Birds - Short term dietary (LC50/LD50) | - | - | - | |
| Fish - Acute 96 hour LC50 (mg l-1) | 100 | F4 Oncorhynchus mykiss | Moderate | |
| Fish - Chronic 21 day NOEC (mg l-1) | - | - | - | |
| Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) | 2.95 | F4 Daphnia magna | Moderate | |
| Aquatic invertebrates - Chronic 21 day NOEC (mg l-1) | - | - | - | |
| 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) | - | - | - | |
| Non-target plants | - | - | - | |
| - | - | - | ||
| Algae - Acute 72 hour EC50, growth (mg l-1) | 0.016 | K3 Unknown species | Moderate | |
| Algae - Chronic 96 hour NOEC, growth (mg l-1) | - | - | - | |
| Honeybees (Apis spp.) | Contact acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | 16 | K4 | Moderate |
| Oral acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | - | - | - | |
| Unknown mode acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | - | - | - | |
| Bumblebees (Bombus spp.) | Contact acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | - | - | - |
| - | ||||
| Oral acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | - | - | - | |
| - | ||||
| Mason bees (Osmia spp.) | Contact acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | - | - | - |
| Oral acute LD50 (worst case from 24 , 48 and 72 hour values - μg bee-1) | - | - | - | |
| Other pollinators (1) | Acute LD50 (worst case from 24 , 48 and 72 hour values - μg insect-1) | - | - | - |
| Mode of exposure | - | |||
| Other pollinators (2) | Acute LD50 (worst case from 24 , 48 and 72 hour values - μg insect-1) | - | - | - |
| Mode of exposure | - | |||
| Earthworms - Acute 14 day LC50 (mg kg-1) | - | - | - | |
| Earthworms - Chronic NOEC, reproduction (mg kg-1) | - | - | - | |
| Other soil macro-organisms | Acute LC50 (mg kg-1) | - | - | - | Chronic NOEC (mg kg-1) | - | - | - |
| Other arthropod (1) | LR50 g ha-1 | - | - | - |
| % Effect | - | - | - | |
| Other arthropod (2) | LR50 g ha-1 | - | - | - |
| % Effect | - | - | - | |
| Soil micro-organisms | - | - | - | |
| Mesocosm study data | NOEAEC mg l-1 | - | - | - |
| NOEAEC mg l-1 | - | - | - | |
HUMAN HEALTH AND PROTECTION
for chloroxuron
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) | > 3700 | V3 Rat | Low | |
| Mammals - Dermal LD50 (mg kg-1 body weight) | - | - | - | |
| Mammals - Inhalation LC50 (mg l-1) | - | - | - | |
| Other Mammal toxicity endpoints | - | - | ||
| ADI - Acceptable Daily Intake (mg kg-1bw day-1) | - | - | - | |
| ARfD - Acute Reference Dose (mg kg-1bw day-1) | - | - | - | |
| AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) | - | - | - | |
| AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) | - | - | - | |
| Dermal penetration studies (%) | - | - | - | |
| Dangerous Substances Directive 76/464 | - | - | - | |
| Exposure Routes | Public | - | ||
| Occupational | Occupational exposure may occur through inhalation of dusts and dermal contact | |||
| 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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- |
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| Respiratory tract irritant | Skin irritant | Skin sensitiser | Eye irritant | Phototoxicant | ||||
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| General human health issues | Harmful by ingestion and inhalation May be harmful by skin contact Under certain conditions may form carcinogenic dimethylnitrosamine |
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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 : Yes, known to cause a problem  : No, known not to cause a problem  : Possibly, status not identified - : No data found |
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Handling issues:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| General |
Fire may produce irritating or poisonous gases | |||
| CLP classification 2013 | Health: H332 Environment: H400 |
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| EC Risk Classification |
Xn - Harmful: R20, R22 | |||
| EC Safety Classification |
- | |||
| WHO Classification | U | - | Unlikely to present an acute hazard | |
| UN Number | - | |||
| Waste disposal & packaging |
- | |||
| Language | Name |
| English | chloroxuron |
| French | chloroxuron |
| German | Chloroxuron |
| Danish | chloroxuron |
| Italian | cloroxuron |
| Spanish | cloroxuron |
| Greek | - |
| Slovenian | kloroksuron |
| Polish | chloroksuron |
| Swedish | - |
| Hungarian | - |
| Dutch | chloroxuron |
Record last updated: Friday 28 June 2019
Contact: aeru@herts.ac.uk