Mecoprop-P (Ref: BAS 037H)

Mecoprop-P (Ref: BAS 037H)	Last updated: 12/01/2021
(Also known as: CMPP-P; MCPP-P; mechlorprop-P; RP 591066)

GENERAL INFORMATION

Description

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

1987, Germany

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/01/2024

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

31/01/2021

EU Candidate for substitution (CfS)

Listed in EU database

Yes

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
✓			✓	✓	✓		✓	✓

Also used in

Australia

Chemical structure

Isomerism

Mecoprop-P is the herbicidally active D+ isomer of chiral mecoprop.

Chemical formula

C₁₀H₁₁ClO₃

Canonical SMILES

CC1=C(C=CC(=C1)Cl)OC(C)C(=O)O

Isomeric SMILES

CC1=C(C=CC(=C1)Cl)O[C@H](C)C(=O)O

International Chemical Identifier key (InChIKey)

WNTGYJSOUMFZEP-SSDOTTSWSA-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)/t7-/m1/s1

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
mecoprop	Isomer

General status

Pesticide type

Herbicide

Substance group

Aryloxyalkanoic acid

Minimum active substance purity

890 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

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

CAS RN

16484-77-8

EC number

240-539-0

CIPAC number

475

US EPA chemical code

129046

PubChem CID

185588

Molecular mass

214.65

PIN (Preferred Identification Name)

IUPAC name

(R)-2-(4-chloro-o-tolyloxy)propionic acid

CAS name

(2R)-2-(4-chloro-2-methylphenoxy)propanoic acid

Other status information

Potential groundwater contaminant

Relevant Environmental Water Quality Standards

Herbicide Resistance Classification (HRAC)

Herbicide Resistance Classification (WSSA)

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

bromoxynil

carfentrazone-ethyl

dicamba

MCPA

iron sulphate

Formulations

Property

Value

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

Compitox Plus
Di-Farmon R
Foundation
Optica
Prompt
Relay P

Example products using this active

BASF
Belchim
Certis
Headland
Nufarm
Scotts

Formulation and application details

Often supplied as soluble concentrate that is mixed with water and used as a spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

250000

High

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

1000000

Acetone

1000000

Ethyl acetate

1000000

Methanol

314000

p-Xylene

Melting point (°C)

93.5

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

240

Flashpoint (°C)

Not expected to self ignite; Not highly flammable

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

6.46 X 10^-01

Calculated

Log P

-0.19

Low

Bulk density (g ml⁻¹)

1.31

Dissociation constant pKa) at 25 °C

3.7

Weak acid

Vapour pressure at 20 °C (mPa)

0.23

Low volatility

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

5.70 X 10^-05

Non-volatile

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

Neutral soln: 229nm=9530, 280nm=1470, 285nm=1290, no absorption above 400nm
Acid soln: 227nm=8860, 279nm=1340, 284 nm=1770, no absorption above 400nm
Alkaline soln: 229nm=9520, 280nm=1560, 289nm=1360, no absorption above 400nm

Surface tension (mN m⁻¹)

at 20 °C 99.8%

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

5.24

Non-persistent

DT₅₀ (lab at 20 °C)

5.24

Non-persistent

DT₅₀ (field)

Non-persistent

DT₉₀ (lab at 20 °C)

Non-persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 4.0-8.2 days, DT₉₀ range 23.1-33.6 days, Soils=3; Other field studies: DT₅₀ 5-17 days

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

Stable

Note

pH sensitive: DT₅₀ 42 days at pH 5, 44 days at pH 7, 32 days at pH 9 (for mecoprop)

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

Value

Stable

Note

Stable pH 5 to pH 9 at 25 & 70 °C

Water-sediment DT₅₀ (days)

141

Slow

Water phase only DT₅₀ (days)

Stable

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

Mobile

K_foc

59.8

¹/_n

0.85

Notes and range

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

pH sensitivity

Adsorption higher at lower pH

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

2.94

Calculated

High leachability

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

Value

2.07 X 10^-01

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Mobile

Calculated

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

hydroxymethyl-mecoprop-P

HMCPP

Plant; Rat

carboxymecoprop-P

CCPP

Plant; Rat

o-cresol

2-methylphenol

Water (photolysis)

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

Low potential

CT₅₀ (days)

1.1

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

431

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

> 20

Mice

High

(ppm diet)

> 100

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

Rat Reproductive NOAEL

High

Birds - Acute LD₅₀ (mg kg⁻¹)

500

Colinus virginianus

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5600 mg kg feed⁻¹

Unknown species

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

70.9

Coturnix japonica NOAEL

Moderate

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 93

Oncorhynchus mykiss

Moderate

Fish - Chronic 21 day NOEC (mg l⁻¹)

> 50

Oncorhynchus mykiss

Low

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

> 91

Daphnia magna

Moderate

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

22.7

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)

1.6

Lemna gibba

Moderate

Non-target plants

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

16.2

Unknown species

Low

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

Unknown species

Low

Honeybees (Apis spp.)

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

> 83.0

Apis mellifera

Moderate

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

> 83.0

Apis mellifera

Moderate

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)

> 988

Eisenia foetida

Moderate

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

10.8

Eisenia foetida

Moderate

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

52.9

Folsomia candida

Other arthropod (1)

LR₅₀ g ha⁻¹

% Effect

7.7

Mortality / Fecundity [Dose: 1.8 kg ha⁻¹]
Aphidius rhopalosiphi

Other arthropod (2)

LR₅₀ g ha⁻¹

% Effect

Mortality [Dose: 1.064 g ha⁻¹]
Carabus nemoralis

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect

Dose: 33.6 kg ha⁻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)

431

Rat

Moderate

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 2.13

Rat 4 hr (whole body)

Other Mammal toxicity endpoints

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

0.01

Rat SF=100

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

None allocated

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

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

0.04

Rat 90 day SF=100

Dermal penetration studies (%)

1-10

concentration dependent

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

European MRLs

EU MRL pesticide database

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

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
USEPA - some evidence to suggest possible human carcinogen

Handling issues

Property

Value and interpretation

General

Prevent generation of mists
Not explosive or oxidising
IMDG Transport Code is usually 9

CLP classification 2013

Health: H302, H318
Environment: H411

EC Risk Classification

Xn - Harmful: R22, R41
N - Dangerous for the environment: R51, R53

EC Safety Classification

S2, S13, S26, S37/39, S60, S61

WHO Classification

II (Moderately hazardous)

UN Number

Usually 3082

Waste disposal & packaging

Packaging Group III (minor danger)

TRANSLATIONS

Language

Name

English

mecoprop-P

French

mecoprop-P

German

Mecoprop-P

Danish

mechlorprop-P

Italian

mecoprop-P

Spanish

mecoprop-P

Greek

mecoprop-P

Polish

mekoprop-P

Swedish

mekoprop-P

Hungarian

mecoprop-P

Dutch

mecoprop-P

Record last updated:	12/01/2021
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