Mecoprop-P etexyl (Ref: CA3264)

Mecoprop-P etexyl (Ref: CA3264)	Last updated: 03/03/2024
(Also known as: mecoprop-P 2-ethylhexyl ester; mecoprop-P 2-EHE; G800A)

SUMMARY

Data alerts

The following alerts are based on the data in the tables below. An absence of an alert does not imply the substance has no implications for human health, biodiversity or the environment but just that we do not have the data to form a judgement.

Environmental fate	Ecotoxicity	Human health
Environmental fate High alert: Drainflow: Mobile	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate Warning: Significant data are missing	Human health High alert: Reproduction/development effects

GENERAL INFORMATION

Description

Mecoprop-P etexyl rapidly breaks to mecoprop-P which is a herbicide for post-emergence control of broad-leaved weeds on grass

Example pests controlled

Cleavers; Chickweed; Clover; Plantains; Ground ivy; Knotweed; Bluegrasses; Bent grass

Example applications

Lawns; Sports fields; Golf courses; Fairways; Cereals including wheat, barley, oats, triticale

Efficacy & activity

Well established herbicide used across the Europe for broad leaved weed control for many years.

Availability status

Current

Introduction & key dates

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/01/2027

UK LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

UK/Ireland

Date EC 1107/2009 inclusion expires

31/01/2024

EU Candidate for substitution (CfS)

Listed in EU database

Yes - as mecoprop-P

Approved for use (✓) under EC 1107/2009 in the following EU Member States

ATAustria	BEBelgium	BGBulgaria	CYCyprus	CZCzech Republic	DEGermany	DKDenmark	EEEstonia	ELGreece
✓	✓	✓	✓	✓	✓		✓	✓
ESSpain	FIFinland	FRFrance	HRCroatia	HUHungary	IEIreland	ITItaly	LTLithuania	LULuxembourg
✓	✓	✓	✓	✓	✓	✓	✓	✓
LVLatvia	MTMalta	NLNetherlands	PLPoland	PTPortugal	RORomania	SESweden	SISlovenia	SKSlovakia
✓		✓	✓	✓			✓

Approved for use (✓) under EC 1107/2009 by Mutual Recognition of Authorisation and/or national regulations in the following EEA countries

ISIceland	NONorway

Additional information

Also used in

Chemical structure

Isomerism

This substance is the herbicidally active D+ isomer of a variant of chiral mecoprop

Chemical formula

C₁₈H₂₇ClO₃

Canonical SMILES

CCCCC(CC)COC(=O)C(C)OC1=C(C=C(C=C1)Cl)C

Isomeric SMILES

CCCCC(CC)COC(=O)[C@@H](C)OC1=C(C=C(C=C1)Cl)C

International Chemical Identifier key (InChIKey)

NWTKQOOQEPXMMW-GICMACPYSA-N

International Chemical Identifier (InChI)

InChI=1S/C18H27ClO3/c1-5-7-8-15(6-2)12-21-18(20)14(4)22-17-10-9-16(19)11-13(17)3/h9-11,14-15H,5-8,12H2,1-4H3/t14-,15?/m1/s1

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
mecoprop	Parent

General status

Pesticide type

Herbicide

Substance groups

Phenoxypropionic herbicide

Minimum active substance purity

890 g kg⁻¹

Known relevant impurities

Substance origin

Synthetic

Mode of action

Selective, systemic, absorbed through leaves and translocated to roots. Synthetic auxin.

CAS RN

861229-15-4

EC number

630-324-3

CIPAC number

475

US EPA chemical code

PubChem CID

24843401

CLP index number

No data found

Molecular mass

326.86

PIN (Preferred Identification Name)

(2E)-2-ethylhexyl (2R)-2-(4-chloro-2-methylphenoxy)propanoate

IUPAC name

(RS)-2-ethylhexyl (R)-2-[(4-chloro-o-tolyl)oxy]propionate

CAS name

2-ethylhexyl (2R)-2-(4-chloro-2-methylphenoxy)propanoate

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Herbicide Resistance Class (WSSA MoA class)

Insecticide Resistance Class (IRAC MoA class)

Not applicable

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Physical state

Liquid with sweet characteristic odour

Related substances & organisms

mecoprop-P

mecoprop-P dimethylammonium

mecoprop-P isobutyl

mecoprop-P potassium

Formulations

Property

Value

Example manufacturers & suppliers of products using this active now or historically

Example products using this active

Formulation and application details

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

0.001

Low

Solubility - In organic solvents at 20 °C (mg l⁻¹)

1000000

Octanol

1000000

Methanol

1000000

Ethyl acetate

1000000

Acetone

Melting point (°C)

-25

Freezing pt

Boiling point (°C)

Degradation point (°C)

200

Flashpoint (°C)

Octanol-water partition coefficient at pH 7, 20 °C

6.03 X 10⁰³

Calculated

Log P

3.78

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Does not dissociate

Vapour pressure at 20 °C (mPa)

0.24

Low volatility. If applied directly to plants, drift is a concern & mitigation is advisable

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

Moderately volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

Distilled water: 228nm=1040, 280nm=1670, 287nm=1450
0.1M HCl: 228nm=1020, 280nm=1640, 287nm=1420
0.1M NAOH: 230nm=10500, 261nm=1820, 288nm=1610

Surface tension (mN m⁻¹)

65.4

92.6%

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

3.04

Non-persistent

DT₅₀ (lab at 20 °C)

3.04

Non-persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

10.15

Non-persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

0.68

(geometric)

Note

EU 2021 dossier: Lab studies DT₅₀ (measured) range 0.35-12.9 days, DT₉₀ (measured) range1.75-42.7 days, Soils=5

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Moderately fast

Note

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

Stable

Note

Stable at all relevant pH values

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Air degradation

As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

K_oc

Notes and range

Freundlich

K_f

1.54

as mecoprop-P

Mobile

K_foc

59.8

¹/_n

0.85

Notes and range

Data for mecoprop-P: EU 2016 RAR dossier K_f range 0.3-4.5 mL g⁻¹, K_foc range 12-167 mL g⁻¹, ¹/_n range 0.66-1.01, Soils=10. Note Mecoprop-P etexyl is expected to have a much higher K_oc/K_foc than the acid.

pH sensitivity

For mecoprop-P adsorption is higher at lower pH

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.07

Calculated

Low leachability

SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate

Value

2.42 X 10^-03

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Mobile

Calculated

Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

Known soil metabolites

Metabolite

Major/Minor fraction

$Click here for further information on Major/Minor fraction$

Estimated maximum occurrence fraction

Notes

mecoprop-P (Ref: BAS 037H)

Major fraction

Known groundwater metabolites

None

Other known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 1400

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2250

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

Soil micro-organisms

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

Honeybees (Apis 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)

> 200

Apis mellifera

Low

Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

> 200

Apis mellifera

Low

Chronic

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 bee species (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other bee species (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Beneficial insects (Ladybirds)

Beneficial insects (Lacewings)

Beneficial insects (Parasitic wasps)

Beneficial insects (Predatory mites)

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 1.54

Oncorhynchus mykiss

Moderate

Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)

Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (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)

Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)

Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)

Mesocosm study data

NOEAEC mg l⁻¹

HUMAN HEALTH AND PROTECTION

General

Property

Value

Source; quality score; and other information

Interpretation

Threshold of Toxicological Concern (Cramer Class)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 1400

Rat

Moderate

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

4.66

Rat

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

0.01

as mecoprop-P

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

None allocated

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

0.2

Rabbit SF=100 as mecoprop-P

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

0.04

as mecoprop-P

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders identified

Occupational

No unacceptable risks to operators or other workers using PPE/PPC identified

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Mammalian dose elimination route and rate

Excreted mainly via urine - 95% in 24 hrs

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

General human health issues

Possible kidney & liver toxicant

Handling issues

Property

Value and interpretation

General

Not expected to auto-ignite, Not highly flammable
Not explosive or oxidising
IMDG Transport Hazard Class 9

CLP classification 2013

Health: H302, H317
Environment: H400, H410

WHO Classification

Not listed (Not listed)

UN Number

UN3077

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

mecoprop-P etexyl

French

German

Danish

Italian

Spanish

Greek

Polish

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	03/03/2024
Contact:	aeru@herts.ac.uk
Please cite as:	Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242