| mecoprop (Ref: RD 4593) |
 |
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GENERAL INFORMATION 
for mecoprop
Description: A post-emergence herbicide used to control broad-leaved weeds on non-crop areas
Example pests controlled: Cleavers; Chickweed; Plantains; Clover; Ground ivy; Dandelions
Example applications: Turf including lawns, sports fields; Commercial sod production; Drainage ditches; Rights-of-way
Efficacy & activity: -
Availability status: Current
Introduction & key dates: circa 1956
EC Regulation 1107/2009 (repealing 91/414):
| Status | Not approved |
| Dossier rapporteur/co-rapporteur | Denmark |
| Date inclusion expires | Not applicable |
| 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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Also used in: Australia, USA
Chemical structure:
| Isomerism | Technical mecoprop is chiral and an isomeric mixture of enantiomers of which only one form, the D+ isomer is herbicidally active and which is contained in the racemate in equal proportion to the L- form. |
| Chemical formula | C10H11ClO3 |
| Canonical SMILES | CC1=C(C=CC(=C1)Cl)OC(C)C(=O)O |
| Isomeric SMILES | No data |
| International Chemical Identifier key (InChIKey) | WNTGYJSOUMFZEP-UHFFFAOYSA-N |
| International Chemical Identifier (InChI) | InChI=1S/C10H11ClO3/c1-6-5-8(11)3-4-9(6)14-7(2)10(12)13/h3-5,7H,1-2H3,(H,12,13) |
| 2D structure diagram/image available? | Yes |
Cambridge Crystallographic Data Centre diagrams:
| Common Name | Relationship | Link |
| Mecoprop | Unstated isomer |  |
General status:
| Pesticide type | Herbicide | |||
| Substance group | Aryloxyalkanoic acid | |||
| Minimum active substance purity | 930 g/kg | |||
| Known relevant impurities | EU dossier - None declared | |||
| Substance origin | Synthetic | |||
| Mode of action | Selective, systemic, absorbed by leaves with translocation. Synthetic auxin. | |||
| CAS RN | 7085-19-0 | |||
| Alternative/old CAS RN | 93-65-2 | |||
| EC number | 202-264-4 | |||
| CIPAC number | 51 | |||
| US EPA chemical code | 031501 | |||
| PubChem CID | 7153 | |||
| Molecular mass (g mol-1) | 214.65 | |||
| PIN (Preferred Identification Name) | - | |||
| IUPAC name | (RS)-2-(4-chloro-o-tolyloxy)propionic acid | |||
| CAS name | 2-(4-chloro-2-methylphenoxy)propanoic acid | |||
| Other status information | Potential groundwater contaminant | |||
| Relevant Environmental Water Quality Standards | UK statutory standard for surface water quality: ‘Good’ for freshwater, transitional and coastal waters 20 ug/L | |||
| Herbicide Resistance Classification (HRAC) | O | |||
| Herbicide Resistance Classification (WSSA) | 4 | |||
| Insecticide Resistance Classification (IRAC) | Not applicable | |||
| Fungicide Resistance Classification (FRAC) | Not applicable | |||
| Examples of recorded resistance | - | |||
| Physical state | White to light brown crystalline 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 liquid concentrate or as an emulsifiable concentrate. | |||
ENVIRONMENTAL FATE
for mecoprop
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Solubility - In water at 20oC (mg l-1) | 250000 | A5 | High | |
| Solubility - In organic solvents at 20oC (mg l-1) | 4110 | A5 - n-Heptane | - | |
| 126000 | A5 - Xylene | - | ||
| 1000000 | A5 - Methanol | - | ||
| 469000 | A5 - Ethyl acetate | - | ||
| Melting point (oC) | 94 | A5 | - | |
| Boiling point (oC) | - | - | - | |
| Degradation point (oC) | - | - | - | |
| Flashpoint (oC) | Not expected to self ignite; Not highly flammable | A5 | - | |
| Octanol-water partition coefficient at pH 7, 20oC | P | 6.46 X 10-01 | Calculated | - |
| Log P | -0.19 | A5 | Low | |
| Bulk density (g ml-1)/Specific gravity | 1.37 | A5 | - | |
| Dissociation constant (pKa) at 25oC | 3.11 | A5 | - | |
| Note: Weak acid | ||||
| Vapour pressure at 20oC (mPa) | 1.6 | A5 | Low volatility | |
| Henry's law constant at 25oC (Pa m3 mol-1) | 2.20 X 10-04 | A5 | Non-volatile | |
GUS leaching potential index  |
2.29 | Calculated | Transition state | |
| SCI-GROW groundwater index (μg l-1) for a 1 kg ha-1 or 1 l ha-1 application rate |
Value | 2.90 X 10-02 | Calculated | - |
| Note | - | |||
| Potential for particle bound transport index |
- | Calculated | Low | |
| 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) | 8.2 | A5 | Non-persistent |
| DT50 (lab at 20oC) | 8.2 | A5 | Non-persistent | |
| DT50 (field) | - | - | - | |
| DT90 (lab at 20oC) | - | - | - | |
| DT90 (field) | - | - | - | |
| DT50 modelling endpoint | - | - | - | |
| Note: | - | |||
| Dissipation rate RL50 on plant matrix | Value | - | - | - |
| Note | - | |||
| Dissipation rate RL50 on and in plant matrix | Value | 3.8 | R4 | - |
| Note | Published literature RL50 range 3.0-4.7 days, 2 field crops, various matrices, n=2 | |||
| Aqueous photolysis DT50 (days) at pH 7 | Value | 44 | A5 | Stable |
| Note | pH sensitive: DT50 42 days at pH 5, 44 days at pH 7, 32 days at pH 9 | |||
| Aqueous hydrolysis DT50 (days) at 20oC and pH 7 | Value | Stable | A5 | - |
| Note | Stable pH 5 to pH 9 up to 70 degC, 8 days | |||
| Water-sediment DT50 (days) | 50 | A5 | Moderately fast | |
| Water phase only DT50 (days) | 37 | A5 | Stable | |
Soil adsorption and mobility:
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Linear | Kd | - | DW3 | Mobile |
| Koc | 47 | |||
| Notes and range | - | |||
| Freundlich | Kf | 0.41 | A4 | Mobile |
| Kfoc | 31 | |||
| 1/n | - | |||
| Notes and range | EU dossier Kf range 0.2-0.69 mL/g, Kfoc range 20-43 mL/g, Soils=4 | |||
| pH sensitivity | Adsorption higher at lower pH | |||
Key metabolites:
| Metabolite | Formation medium | Estimated maximum occurrence fraction | 1107/2009 relevancy |
|
| 2-methyl-4-chlorophenol | Soil | 0.035 | Minor fraction, Relevancy unknown | |
| Property |
Value | Source/Quality Score/Other Information |
Interpretation |
|
| Bio-concentration factor | BCF (l kg-1) | 3 | A5 | Low potential |
| CT50 (days) | 1.1 | - | ||
| Mammals - Acute oral LD50 (mg kg-1) | 1166 | A5 Rat | Moderate | |
| Mammals - Short term dietary NOEL | (mg kg-1) | 11.4 | A5 Rat | High |
| (ppm diet) | 150 | - | ||
| Birds - Acute LD50 (mg kg-1) | > 500 | A5 Anas platyrhynchos | Moderate | |
| Birds - Short term dietary (LC50/LD50) | 5000 mg kg feed-1 | A5 Anas platyrhynchos | - | |
| Fish - Acute 96 hour LC50 (mg l-1) | 240 | A4 Unknown species | Low | |
| Fish - Chronic 21 day NOEC (mg l-1) | 109 | A5 Oncorhynchus mykiss | Low | |
| Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) | > 200 | A4 Daphnia magna | Low | |
| Aquatic invertebrates - Chronic 21 day NOEC (mg l-1) | 22.0 | A5 Daphnia magna | Low | |
| 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) | 40.2 | A4 Unknown species | Low | |
| Non-target plants | - | - | - | |
| - | - | - | ||
| Algae - Acute 72 hour EC50, growth (mg l-1) | 237 | A4 Unknown species | Low | |
| Algae - Chronic 96 hour NOEC, growth (mg l-1) | 56 | Q2 Unknown species | Low | |
| Honeybees | Contact acute 48 hour LD50 (μg bee-1) | > 100 | A5 | Low |
| Oral acute 48 hour LD50 (μg bee-1) | > 100 | A5 | Low | |
| Unknown mode acute 48 hour LD50 (μg bee-1) | - | - | - | |
| Earthworms - Acute 14 day LC50 (mg kg-1) | 988 | A5 | Moderate | |
| Earthworms - Chronic 14 day NOEC, reproduction (mg kg-1) | - | - | - | |
| Other soil macro-organisms - e.g. Collembola | LR50 / EC50 / NOEC / % Effect | - | - | - |
| Other arthropod (1) | LR50 g ha-1 | - | - | - |
| % Effect | -28 | Mortality Dose: 3.36 g ha-1 A5 Carabus nemoralis |
- | |
| Other arthropod (2) | LR50 g ha-1 | - | - | - |
| % Effect | 0 | Beneficial effect Dose: 3.36 g ha-1 A5 Philonthus marginatus |
- | |
| Soil micro-organisms | Nitrogen mineralisation: No significant adverse effect Carbon mineralisation: No significant adverse effect |
A5 Dose: 33.6 kg ha-1 |
- | |
| Mesocosm study data | NOEAEC mg l-1 | - | - | - |
| NOEAEC mg l-1 | - | - | - | |
HUMAN HEALTH AND PROTECTION
for mecoprop
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) | 1166 | A5 Rat | Moderate | |
| Mammals - Dermal LD50 (mg kg-1 body weight) | > 4000 | A5 Rat | - | |
| Mammals - Inhalation LC50 (mg l-1) | 12.5 | A5 Rat (nose only) | - | |
| 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) | None allocated | A5 | - | |
| AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) | - | - | - | |
| AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) | 0.04 | A5 Rat, 90 day, SF=100 | - | |
| Dermal penetration studies (%) | 20 | A5 | - | |
| Dangerous Substances Directive 76/464 | List II | - | - | |
| Exposure Limits | - | - | - | |
| Exposure Routes | Public | No unacceptable risks to bystanders identified | ||
| Occupational | No unacceptable risks to operators or other workers identified | |||
| European MRLs | Click here for the EU MRL pesticide database | |||
| Drinking Water Standards | Non-statutory WHO drinking water guideline 0.01 mg/L | UK EA QS database, 2018 | - | |
| 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 | No further information available | |||||||
: 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 |
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| General |
Hydrogen Chloride (HCl), and phosgene may be formed in a fire IMDG Transport Code is usually 6.1 |
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| CLP classification 2013 | Health: H302, H315, H318 Environment: H400, H410 |
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| EC Risk Classification |
Xn - Harmful: R22, R41 Xi - Irritant: R38 N - Dangerous for the environment: R50, R53 |
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| EC Safety Classification |
S2, S13, S26, S37/39, S60, S61 | |||
| WHO Classification | II | - | Moderately hazardous | |
| US EPA Classification (formulation) | III | - | Caution - Slightly toxic | |
| UN Number | Usualy 2811 | |||
| Waste disposal & packaging |
Packaging Group III (minor danger) | |||
| Language | Name |
| English | mecoprop |
| French | mecoprop |
| German | Mecoprop |
| Danish | mechlorprop |
| Italian | mecoprop |
| Spanish | mecoprop |
| Greek | mecoprop |
| Slovenian | mekoprop |
| Polish | mekoprop |
| Swedish | mekoprop |
| Hungarian | mecoprop |
| Dutch | mecoprop |
Record last updated: Wednesday 31 October 2018
Contact: aeru@herts.ac.uk