Ethofumesate (Ref: AE B049913)

Ethofumesate (Ref: AE B049913)	Last updated: 28/02/2025
(Also known as: NC 8438; SN 49913; HBX06)

SUMMARY

Ethofumesate is a pre- and post-emergence selective herbicide for grasses and broadleaved weed control. It is moderately soluble in water and highly soluble in many organic solvents. It is not considered to be volatile, nor is it usually persistent in soil systems. It is moderately mobile in the environment and so may leach to groundwaters. Ethofumesate has a low to moderate ecotoxicity for many species although there are gaps in data. No serious human health issues have been identified.

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: GUS: High leachability	Ecotoxicity Moderate alert: 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: Mammals chronic toxicity: Moderate; Reproduction/development effects

GENERAL INFORMATION

Description

A pre- and post-emergence herbicide for grasses and broadleaved weed control in various crops

Example pests controlled

Black nightshade; Chickweed; Lambsquarters; Purslane; Pigweed; Thistles; Annual bluegrass; Foxtails; Volunteer cereals; White grass

Example applications

Sugarbeet; Red beet; Fodder beet; Onions, gallic & shallots; Carrots; Grass seed crops; Oilseed poppies

Efficacy & activity

Availability status

Current

Introduction & key dates

1969, first reported; 1974, first introduced

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/10/2031

GB LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Austria/Denmark

Date EC 1107/2009 inclusion expires

31/10/2031

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; Morocco

Chemical structure

Isomerism

A chiral molecule, ethofumesate is an isomeric mixture

Chemical formula

C₁₃H₁₈O₅S

Canonical SMILES

CCOC1C(C2=C(O1)C=CC(=C2)OS(=O)(=O)C)(C)C

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

IRCMYGHHKLLGHV-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C13H18O5S/c1-5-16-12-13(2,3)10-8-9(18-19(4,14)15)6-7-11(10)17-12/h6-8,12H,5H2,1-4H3

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Benzofuranyl alkylsulfonate herbicide

Minimum active substance purity

960 g kg⁻¹ active, max 5 g kg⁻¹ water

Known relevant impurities

EU dossier (RAR) - methanesulfonic acid ethyl ester < 0.1 mg kg⁻¹; 1,1-dimethyl-2-((methylsulfonyl)oxy)-ethyl < 0.1 mg kg⁻¹

Substance origin

Synthetic

Mode of action

Selective, systemic, absorbed through emerging shoots and roots. Inhibition of lipid synthesis.

CAS RN

26225-79-6

EC number

247-525-3

CIPAC number

233

US EPA chemical code

110601

PubChem CID

33360

CLP index number

607-314-00-2

Molecular mass

286.34

PIN (Preferred Identification Name)

rac-(2R)-2-ethoxy-3,3-dimethyl-2,3-dihydro-1-benzofuran-5-yl methanesulfonate

IUPAC name

(RS)-2-ethoxy-2,3-dihydro-3,3-dimethylbenzofuran-5-yl methanesulfonate

CAS name

2-ethoxy-2,3-dihydro-3,3-dimethyl-5-benzofuranyl methanesulfonate

Other status information

Potential groundwater contaminant

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

White to beige coloured crystalline solid

Formulations

Property

Value

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

AgriGuard
BASF
Makhteshim-Agan
Nufarm UK
Bayer CropScience

Example products using this active

Betanal Expert
Ethosat 500
Galahad
Goltix Super
Magnum
Nortron Flow
Twin
Ethofumesate SC 500
Ethofol 500 SC

Formulation and application details

Often supplied as a soluble concentrate which is 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)

at 25 °C

Moderate

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

260000

Acetone

600000

Dichloromethane

600000

Ethyl acetate

114000

Methanol

Melting point (°C)

70.7

Boiling point (°C)

Decomposes before / on boiling @ 305-320 Deg C

Degradation point (°C)

>220

Flashpoint (°C)

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

5.01 X 10⁰²

Calculated

Log P

2.7

Moderate

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data

Density (g ml⁻¹)

1.3

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.65

at 25 °C

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)

3.72 X 10^-03

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

Negligible

From soil surface

Negligible

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

Neutral pH: 203nm=19441; 228nm=7228; 281nm=2797; 291nm=1412
Acidic pH: 202nm=24122; 227nm=7339; 280nm=2797; 291nm=1357
Basic pH: 202.5nm=17362; 227nm=6716; 280.5nm=2546

Surface tension (mN m⁻¹)

68.3

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

21.6

Non-persistent

DT₅₀ (lab at 20 °C)

21.6

Non-persistent

DT₅₀ (field)

37.8

Moderately persistent

DT₉₀ (lab at 20 °C)

100.6

Persistent

DT₉₀ (field)

264

DT₅₀ modelling endpoint

Note

EU dossier (2016) lab studies DT₅₀ range 8.5-80.5 days, DT₅₀ range 38.7-228 days, Soils =18; Field studies DT₅₀ range 13.5-110 days, DT₉₀ range 72-522 days, Soils = 13; Other data DT₅₀ 30 days (DW4)

Dissipation rate RL₅₀ (days) on plant matrix

Value

6.2

Note

Ryebrass blades, n=1

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

3.0

Note

Creeping bent blades, n=1

Aqueous photolysis DT₅₀ (days) at pH 7

Value

15.6

Slow

Note

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

Value

Stable

Note

Stable pH 5 to pH 9.2

Water-sediment DT₅₀ (days)

591

Stable

Water phase only DT₅₀ (days)

Slow

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)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

1.74

Moderately mobile

K_foc (mL g⁻¹)

118

¹/_n

0.91

Notes and range

EU dossier (2016) K_f range 0.7-6.2 mL g⁻¹, K_foc range 48-247 mL g⁻¹, ¹/_n range 0.84-0.96, Soils=12

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

3.04

Calculated

High leachability

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

Value

2.99 X 10^-01

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

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

4.1

Calculated using the Atkinson method. Assumed 0.5E+06 OH/cm³, 24 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

144

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

2,3-dihydro-2-hydroxy-3,3-dimethylbenzofuran-5-yl-methanesulfonate (Ref: NC 8493)

Major fraction

0.240

Bayer verified

2-(2-hydroxy-5-methanesulfonylphenyl)-2-methyl propionic acid (Ref: NC 20645)

Major fraction

Bayer verified; Max occurrence fraction not specified, occcurrence in free and conjugatzed form in lysimeter leachates

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)

> 2000

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

Rabbit

(ppm diet)

300

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

60.9

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5200 mg kg feed⁻¹

Anas platyrhynchos

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

265

Colinus virginianus NOEL

Low

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

134

Eisenia foetida

Moderate

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

> 4.42

Eisenia foetida 56 day corr

Moderate

Soil micro-organisms

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

Dose: up to 13.8 mg kg⁻¹ soil 42 Day

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

13.35

Folsomia candida corr

Non-target plants

> 2.0

Avena sativa
Vegetative vigour, ER₅₀
as L product SC 500 /ha

0.328

Avena sativa
Seedling emergence, ER₅₀
as L product SC 500/ha

Honeybees (Apis spp.)

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

> 50

Apis mellifera

Moderate

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

> 50

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

> 4.4

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) as Mortality LR₅₀ g ha⁻¹

> 2000

Chrysoperla carnea

Beneficial insects (Parasitic wasps) as Mortality LR₅₀ g ha⁻¹

> 1000

Aphidius rhopalosiphi

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

> 1000

Typhlodromus pyri

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)

10.92

Cyprinus carpio

Moderate

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

0.156

Danio rerio

Moderate

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

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

13.52

Daphnia magna

Moderate

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

0.25

Daphnia magna

Moderate

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

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

4.5

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)

3.82

Chironomus riparius

Moderate

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

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

> 52.8

Lemna minor

Low

Aquatic plants (rooted, growth) - Acute 14 day EC₅₀, biomass (mg l⁻¹)

0.479

Myriophyllum spicatum

Moderate

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

3.9

Raphidocelis subcapitata

Moderate

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

9.68

Pseudokirchneriella subcapitata

Low

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)

Low (class I)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 0.16

Rat 4 hr (whole body)

Other Mammal toxicity endpoints

Intraperitoneal LD₅₀ > 2000 mg kg⁻¹ bw

Rat

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

1.00

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

None allocated

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

None allocated

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

2.5

Dermal penetration studies (%)

0.4-8

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Minimal risk of dietary exposure
Minimal risk to bystanders and residents

Occupational

Minimal risk for operators and farm workers

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

GB MRL modified for onions, shallots & garlic Jan 2024 - see UK HSE website

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

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Harmful in contact with skin and if swallowed
Possible liver toxicant

Handling issues

Property

Value and interpretation

General

Prevent generation of mists
IMDG Transport Hazard Class 9
Not explosive or oxidising
Not explected to auto-ignite, Not highly flammable

CLP classification 2013

Environment: H411

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

UN3077

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

Chemically stable under standard ambient condition

TRANSLATIONS

Language

Name

English

ethofumesate

French

ethofumesate

German

Ethofumesat

Danish

ethofumesat

Italian

etofumesate

Spanish

etofumesato

Greek

ethofumesate

Polish

etofumesat

Swedish

etofumesat

Hungarian

etofumezat

Dutch

ethofumesaat

Norwegian

Record last updated:	28/02/2025
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