Carfentrazone-ethyl (Ref: F 8426)

Carfentrazone-ethyl (Ref: F 8426)	Last updated: 22/08/2024
(Also known as: F 116426)

SUMMARY

Carfentrazone-ethyl is a commonly used herbicide. It has a low aqueous solubility, a low volatility and, based on its chemical properties, would not normally be expected to leach to groundwater. It is not normally persistent in soil or water systems. It has a low mammalian toxicity and no significant negative health effects have been identified. It is moderately toxicity to most species.

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 Moderate alert: Drainflow: Slightly mobile	Ecotoxicity Moderate alert: Birds chronic ecotoxicity: Moderate; Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Bees acute contact ecotoxicity: Moderate; Bees acute oral ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate; Earthworms chronic ecotoxicity: Moderate	Human health Moderate alert: Possible Carcinogen

GENERAL INFORMATION

Description

A post-emergence herbicide used to control a wide range of broad-leaved weeds and for foliage desiccation.

Example pests controlled

Broad-leaved weeds including Galium aparine, Abutilon theophrasti, Ipomoea ederacea, Chenopodium album and several mustard species, Sedges, Silvery-thread moss; Sucker control; Foliage desiccation

Example applications

Potatoes; Cereals including barley, oats, tritical, wheat and durum wheat; Vines; Sports turf & golf-coures

Efficacy & activity

Shown to be effective in field trials and from its extensive use globally

Availability status

Current

Introduction & key dates

1997, introduced

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/07/2033

GB LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Belgium/France

Date EC 1107/2009 inclusion expires

31/07/2033

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
✓	✓	✓	✓	✓		✓		✓

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

Australia, USA, Morocco

Chemical structure

Isomerism

A chiral molecule existing in the R- and S-forms. Substance is racemic.

Chemical formula

C₁₃H₁₄Cl₂F₃N₃O₃

Canonical SMILES

CCOC(=O)C(CC1=CC(=C(C=C1Cl)F)N2C(=O)N(C(=N2)C)C(F)F)Cl

Isomeric SMILES

International Chemical Identifier key (InChIKey)

MLKCGVHIFJBRCD-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C15H14Cl2F3N3O3/c1-3-26-13(24)10(17)4-8-5-12(11(18)6-9(8)16)23-15(25)22(14(19)20)7(2)21-23/h5-6,10,14H,3-4H2,1-2H3

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Triazolone herbicide

Minimum active substance purity

910 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Contact, absorbed by foliage with limited translocation. Inhibition of protoporphyrinogen oxidase (PPO) - cell membrane disruption

CAS RN

128639-02-1

EC number

603-291-8

CIPAC number

587

US EPA chemical code

128712

PubChem CID

86222

CLP index number

607-309-00-5

Molecular mass

412.19

PIN (Preferred Identification Name)

rac-ethyl (2R)-2-chloro-3-{2-chloro-5-[4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl]-4-fluorophenyl}propanoate

IUPAC name

ethyl (RS)-2-chloro-3-{2-chloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]-4-fluorophenyl}propionate

CAS name

ethyl α,2-dichloro-5-(4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl)-4-fluorobenzenepropanoate

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

Colourless to yellow viscous liquid depending upon purity

Related substances & organisms

carfentrazone

Formulations

Property

Value

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

AgriGuard
Belchim
DuPont
CropSure Pty Ltd

Example products using this active

Ally Express
Lexus Class
Shark
Carfen
Quicksilver
Aim EC
Spotlight plus
CropSure Carfentrazone 400EC

Formulation and application details

Usually supplied as wettable granules or emulsions that are mixed with water and applied as a spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

29.3

Low

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

2000000

Acetone

900000

Toluene

30000

Hexane

2000000

Ethanol

Melting point (°C)

-22.1

Boiling point (°C)

350

Degradation point (°C)

Flashpoint (°C)

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

5.01 X 10⁰³

Calculated

Log P

3.7

High

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data based on LogP and metabolism studies

Density (g ml⁻¹)

1.46

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.011

Low volatility

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

1.56 X 10^-04

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

In methanol: 244nm =9559, 276nm = 1927
In acidified methanol: 244nm=9811, 276nm=1935
In basic methanol: 219nm=10296, 243nm=10079, 276nm=2120
No absorption after 290nm

Surface tension (mN m⁻¹)

67.7

at 20 °C 98.4%

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

1.0

Non-persistent

DT₅₀ (lab at 20 °C)

1.0

Non-persistent

DT₅₀ (field)

0.5

Non-persistent

DT₉₀ (lab at 20 °C)

38.4

Moderately persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU 2016 dossier lab studies DT₅₀ range 0.1-77.1 days, DT₉₀ range 0.22-307 days, Soils=11

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

5.5

Note

Rice leaves, n=1

Aqueous photolysis DT₅₀ (days) at pH 7

Value

8.3

Moderately fast

Note

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

Value

9.8

Non-persistent

Note

pH sensitive: stable at pH 4, DT₅₀ 3.5 hours at pH 9, 20 °C

Water-sediment DT₅₀ (days)

0.21

Fast

Water phase only DT₅₀ (days)

0.1

Fast

Sediment 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.

Decay in stored produce DT₅₀

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

Slightly mobile

K_oc (mL g⁻¹)

866

Notes and range

Freundlich

K_f (mL g⁻¹)

7.08

Moderately mobile

K_foc (mL g⁻¹)

486.04

¹/_n

1.079

Notes and range

EU 2016 dossier K_f range 3.3-12.7 mL g⁻¹, K_foc range 325-616 mL g⁻¹, ¹/_n range 0.983-1.182, Soils=5

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

-0.40

Calculated

Low leachability

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

Value

8.67 X 10^-05

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Slightly mobile

Calculated

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

25.7

Calculated using the Atkinson method. Assumed 1.5E+06 OH/cm³, 12 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

176

Whole fish

Threshold for concern

CT₅₀ (days)

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

methyl triazole-F8426

Major fraction

0.118

FMC verified

carfentrazone

Major fraction

0.921

FMC verified

3-(2-chloro-5-(4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorophenyl)propanoic acid

Major fraction

0.273

FMC verified

(2E)-3-(2-chloro-5-(4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorophenyl)acrylic acid

Major fraction

0.496

FMC verified

2-chloro-5-(4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorobenzoic acid

Major fraction

0.172

FMC verified

methoxy-F8426-despropionate

Major fraction

0.101

FMC verified

3-hydroxymethyl-F8426-benzoic acid

Major fraction

0.337

FMC verified

F8426-dicarboxylic acid

Major fraction

0.168

FMC verified

3-hydroxymethyl-F8426-propionic acid

Minor fraction

0.078

FMC verified

F8426-alpha-sulfo-deschloropropionic acid

Minor fraction

0.008

FMC verified

Known groundwater metabolites

Metabolite

EC SANCO/221/2000 relevancy

ADI (mg kg⁻¹ bodyweight day⁻¹)

WHO drinking water guidance value (μg L⁻¹ day⁻¹)

3-(2-chloro-5-(4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorophenyl)propanoic acid

Not relevant

(2E)-3-(2-chloro-5-(4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorophenyl)acrylic acid

Not relevant

methoxy-F8426-despropionate

Not relevant

3-hydroxymethyl-F8426-benzoic acid

Not relevant

0.01

3-hydroxymethyl-F8426-propionic acid

Not relevant

F8426-alpha-sulfo-deschloropropionic acid

Not relevant

0.00036

2.16

methyl triazole-F8426

Not relevant

F8428-benzoic acid

Not relevant

0.0054

32.4

F8426-cinnamic acid

Not relevant

F8426-propionic acid

Not relevant

0.0014

8.4

F8426-dicarboxylic acid

Not relevant

0.012

8.4

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

3-(2-Chloro-5-(4-(difluoromethyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorophenyl}propanoic acid

3-desmethyl-F8426-propionic acid

Surface water; Sediment

(2RS)-2-chloro-3-(2-chloro-5-(4-(difluoromethyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorophenyl)propanoic acid

3-desmethyl-F8426-chloropropionic acid

Plant

(2RS)-2-chloro-3-(2-chloro-5-(4-(difluoromethyl)-3-(hydroxymethyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorophenyl)propanoic acid

3-hydroxymethyl-F8426-chloropropionic acid

Plant

2-chloro-5-(4-(difluoromethyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-4-fluorobenzoic acid

3-desmethyl-F8426-benzoic acid

Plant

5-(4-(difluoromethyl)-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)-2,4-dihydroxybenzoic acid

2,4-diOH-F8426-benzoic acid

Surface water; Sediment

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 5000

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

Rat

(ppm diet)

1000

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

323

Rat Reproductive NOAEL

Low

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2250

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5620 ppm

Colinus virginianus

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

Colinus virginianus NOEC

Moderate

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

> 410

Eisenia foetida corr

Moderate

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

17.72

Eisenia foetida corr

Moderate

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect at 61 days
Carbon mineralisation: No significant adverse effect at 28 days

Dose: 0.52 mg kg⁻¹

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

0.101

Folsomia candida EC10 corr

Non-target plants

Honeybees (Apis spp.)

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

> 81

Apis mellifera

Moderate

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

> 81

Apis mellifera

Moderate

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

Chronic as 10-day LDD₅₀ µg bee⁻¹ day⁻¹

Apis mellifera

Notes

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) as Mortality LR₅₀ g ha⁻¹

23.54

Aphidius rhopalosiphi Adult

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹

36.8

Typhlodromus pyri Adult

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)

1.6

Oncorhynchus mykiss

Moderate

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

0.11

Oncorhynchus mykiss

Moderate

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

0.23

Danio rerio EC₅₀ Embryo

Moderate

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

> 9.8

Daphnia magna

Moderate

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

0.22

Daphnia magna

Moderate

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

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

1.01

Americamysis bahia

Moderate

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

7.4

Chironomus riparius

Moderate

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)

0.0057

Lemna gibba

High

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

0.012

Anabaena flos-aquae

Moderate

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

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves

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)

> 5000

Rat

Low

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

4000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 5.09

Rat 4 hr (whole body)

Other Mammal toxicity endpoints

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

0.03

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)

0.4

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

List II

Exposure Routes

Public

Minimal risk of dietary exposure

Occupational

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

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

Possible liver & kidney toxicant
CLP data - suspected carcinogen

Handling issues

Property

Value and interpretation

General

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

CLP classification 2013

Health: H351
Environment: H400, H410

WHO Classification

Not listed (Not listed)

UN Number

UN3082

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

carfentrazone-ethyl

French

carfentrazone-ethyle

German

Carfentrazone

Danish

carfentrazone-ethyl

Italian

carfentazone-etile

Spanish

carfentrazona-etil

Greek

carfentrazone-ethyl

Polish

karfentrazon etylu

Swedish

karfentrazonetyl

Hungarian

karfentrazon-etil

Dutch

carfentrazone-ethyl

Norwegian

karfentrazon-etyl

Record last updated:	22/08/2024
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