Bensulfuron-methyl (Ref: DPX F5384)

Bensulfuron-methyl (Ref: DPX F5384)	Last updated: 31/10/2024
(Also known as: methyl bensulfuron; DPX 84; F 5384)

SUMMARY

Bensulfuron-methyl is a herbicide used to control various weeds and sedges. It is moderately soluble in water, non-volatile and moderately mobile. It would not be expected to persistent in soil but could be persistent in water systems under certain conditions. It is not highly toxic to mammals. It also shows a low toxicity to birds and earthworms but is more of a concern to aquatic plants, algae and honeybees

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: Moderately mobile	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Bees acute oral ecotoxicity: Moderate; Earthworms chronic ecotoxicity: Moderate	Human health Moderate alert: Genotoxic; Reproduction/development effects

GENERAL INFORMATION

Description

A pyrimidinylsulfonylurea herbicide used to control annual and perennial weeds and sedges

Example pests controlled

Pigweed; Chickweed; Wild mustard; Stinkgrass; Barnyardgrass; Rice flatsedge; Dwarf umbrella grass; Nut-grass; Creeping water primrose

Example applications

Cereals especially wheat; Rice

Efficacy & activity

Extensive field trials used to demonstrate efficiacy.

Availability status

Current

Introduction & key dates

1985, introduced

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/10/2031

UK LERAP status

No data

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Italy/Spain

Date EC 1107/2009 inclusion expires

15/08/2026

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

Chemical structure

Isomerism

None

Chemical formula

C₁₆H₁₈N₄O₇S

Canonical SMILES

COC1=CC(=NC(=N1)NC(=O)NS(=O)(=O)CC2=CC=CC=C2C(=O)OC)OC

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

XMQFTWRPUQYINF-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C16H18N4O7S/c1-25-12-8-13(26-2)18-15(17-12)19-16(22)20-28(23,24)9-10-6-4-5-7-11(10)14(21)27-3/h4-8H,9H2,1-3H3,(H2,17,18,19,20,22)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
bensulfuron-methyl	-

General status

Pesticide type

Herbicide

Substance groups

Sulfonylurea herbicide; Pyrimidinylsulfonylurea herbicide

Minimum active substance purity

975 g kg⁻¹

Known relevant impurities

EU 2024 dossier - None declared

Substance origin

Synthetic

Mode of action

Selective, systemic action being absorbed through foliage and roots. Inhibits plant amino acid synthesis - acetohydroxyacid synthase AHAS

CAS RN

83055-99-6

EC number

401-340-6

CIPAC number

502.201

US EPA chemical code

128820

PubChem CID

54960

CLP index number

607-178-00-4

Molecular mass

410.4

PIN (Preferred Identification Name)

methyl 2-({[(4,6-dimethoxypyrimidin-2-yl)carbamoyl]sulfamoyl}methyl)benzoate

IUPAC name

methyl α-[(4,6-dimethoxypyrimidin-2-ylcarbamoyl)sulfamoyl]-o-toluate

CAS name

methyl 2-[[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]methyl]benzoate

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

Alisma plantago-aquatica, Bacopa rotundifolia

Physical state

White to straw coloured solid

Related substances & organisms

bensulfuron

Formulations

Property

Value

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

United Phosphorus
DuPont

Example products using this active

Sectar
Testar
Duet DF Rice Herbicide
Dupont Londax G
Londax 60 DF

Formulation and application details

Usually supplied as water dispersible granules that are 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)

6.65

Low

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

5100

Acetone

18400

Dichloromethane

1750

Ethyl acetate

229

o-Xylene

Melting point (°C)

179.4

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

245

Flashpoint (°C)

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

6.17 X 10⁰⁰

Calculated

Log P

0.79

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data based on LogP

Density (g ml⁻¹)

1.41

Dissociation constant pKa) at 25 °C

5.2

Weak acid

Vapour pressure at 20 °C (mPa)

4.990 X 10^-03

Low volatility

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

3.08 X 10^-07

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

Volatilisation is not considered critical for air pollution

From soil surface

Volatilisation is not considered critical for air pollution

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

Acidic soln: 200nm=51900, 236nm=13600
Neutral soln: 200nm=58200, 239nm=26700
Alkaline soln: 210nm=29200, 240nm=27400

Surface tension (mN m⁻¹)

74.9

at 20 °C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

56.9

Moderately persistent

DT₅₀ (lab at 20 °C)

56.9

Moderately persistent

DT₅₀ (field)

4.5

Non-persistent

DT₉₀ (lab at 20 °C)

203.0

Persistent

DT₉₀ (field)

15.0

DT₅₀ modelling endpoint

Note

EU 2024 dossier lab studies range (normalised) DT₅₀ 35.2-104 days, DT₉₀ range (measured) 80.1-344 days, Soils=3; 2022 field studies DT₅₀ range (measured) 0.3-12.4 days, DT₉₀ range (measured) 1.1-41.3 days, Soils=13

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

Stable

Note

DT₅₀: 10 days irradiated pond water, 90 days irradiated creek water, 29 days irradiated pure water and stable in pure dark water

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

Value

Stable

Note

Sensitive to pH: DT₅₀ 5.9 days at pH 4, 138 days at pH 9 at 25 °C

Water-sediment DT₅₀ (days)

Moderately fast

Water phase only DT₅₀ (days)

18.5

Slow

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)

1.75

Moderately mobile

K_foc (mL g⁻¹)

106.2

¹/_n

0.94

Notes and range

EU 2024 dossier kf range 1.59-1.91 mL g⁻¹, K_foc range 75.8-136.6 mL g⁻¹, ¹/_n range0.937-0.948, Soils=2; EU 2008 dossier kf range 2.5-8.4 mL g⁻¹, K_foc range 205-684 mL g⁻¹, ¹/_n range 0.88-1.08, Soils=7

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.29

Calculated

Low leachability

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

Value

3.58 X 10^-03

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

0.611

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)

1.6

Low potential

CT₅₀ (days)

327

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

4,6-dimethyl-2-pyrimidinamine (Ref: IN J0290)

Major fraction

0.210

methyl 2-((aminosulfonyl)methyl)-benzoate (Ref: IN N5297)

Major fraction

0.124

(((4,6-dimethoxypyrimidin-2-yl)-carbamoyl) sulamoyl)acetic acid (Ref: IN DAT97)

Major fraction

0.436

bensulfuron (Ref: IN R9419)

Major fraction

0.257

2-((aminosulfonyl)methyl)benzoic acid (Ref: IN D1R84)

Major fraction

0.182

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)

(((4,6-dimethoxypyrimidin-2-yl)-carbamoyl) sulamoyl)acetic acid (Ref: IN DAT97)

Relevancy unknown

methyl 2-((aminosulfonyl)methyl)-benzoate (Ref: IN N5297)

Relevancy unknown

bensulfuron (Ref: IN R9419)

Relevancy unknown

2-((aminosulfonyl)methyl)benzoic acid (Ref: IN D1R84)

Not relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

methyl-2-(sulfomethyl) benzoate sodium salt (Ref: IN-68991)

Surface water; Sediment

4,6-dimethoxypyrimidin-2-amine (Ref: IN-J0290)

Rat; Surface water

sulfonylurethan (Ref: IN-JF987)

Rat (urine)

hydroxylated bensulfuron-methyl (Ref: IN-W8956)

Surface water; Sediments; Hen

hydroxybensulfuron-methyl (Ref: UK1)

Human

phenylglyoxylic avid (Ref: IN-YY142)

Surface water

methyl 2-((aminosulfonyl)methyl)-benzoate (Ref: IN N5297)

Surface water; Sediment; Animal (Faeces, Urine); Rat; Human

(((4,6-dimethoxypyrimidin-2-yl)-carbamoyl) sulamoyl)acetic acid (Ref: IN DAT97)

Surface water; Sediment

(4,6-dimethoxypyrimidin-2-yl)urea (Ref: IN-T5831)

Water (Photolysis); Sediment

methyl 2-({[(4-hydroxy-6-methoxypyrimidin-2-yl)carbamoyl]sulfamoyl}methyl)benzoate (Ref: IN-F7880)
Note: Med-high mobility

Surface water; Sediment; Rice; Rat; Human

bensulfuron (Ref: IN R9419)

Rat; Human

methyl-2-((((((5-hydroxy-4,6-pyrimidinyl)amino)carbonyl)-amino)sulfonyl)-emthyl)benzoate (Ref: IN-N8989)

Rat; Human; Surface water; Sediment

methyl-2-((((((aminoiminomethyl)amino)carbonyl)amino)sulfonyl)-methyl)benzoate hydrochloride (Ref: IN-78184)

Plant; Hen

2-amino-6-methoxy-4-pyrimidinol (Ref: IN-H9235)

Rat (urine)

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)

21.4

Rat

High

(ppm diet)

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

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2510

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 1690 mg kg bw⁻¹ day⁻¹

Anas platyrhynchos

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

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

> 1000

Eisenia andrei

Low

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

16.7

Eisenia andrei

Moderate

Soil micro-organisms

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

Dose: 5 x field rate

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

> 2.41

Oilseed rape
Seedling emergence, ER₅₀
as g ha⁻¹

> 2.08

Soybean
Vegetative vigour, ER₅₀
as g ha⁻¹

Honeybees (Apis spp.)

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

> 100

Apis mellifera

Low

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

> 51.4

Apis mellifera

Moderate

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

Chronic as 10 day LC₅₀

> 239

Apis mellifera

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 48 hr

> 600

Aphidius rhopalosiphi Nymph

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹ 7 day

> 600

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)

> 66

Oncorhynchus mykiss

Moderate

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

12.0

Oncorhynchus mykiss

Low

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

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

> 130

Daphnia magna

Low

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

Daphnia magna

Low

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

> 300

Ceriodaphnia dubia

Low

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

130

Americamysis bahia

Low

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

125.0

Chironomus tentans

Low

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)

0.0015

Lemna gibba 14 day

High

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

0.057

Raphidocelis subcapitata

Moderate

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

40.0

Raphidocelis subcapitata

Low

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)

> 2000

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 7.5

Rat 4 hr (whole body)

Other Mammal toxicity endpoints

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

0.2

Dog 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)

None allocated

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

0.12

Dog SF=167

Dermal penetration studies (%)

10-50%

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks identified for proposed uses

Occupational

Risk of exposure acceptable under label recommendations for use for personal protection clothing and equipment

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

0.1

EU Dir 89/778/EC limit; Calc MAC=600 µg l⁻¹

Mammalian dose elimination route and rate

Excretion in urine and faeces usually complete in < 72 hrs

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

General human health issues

Possible liver toxicant
May induce weight decreases, reduce haemoglobin and cause increased risk of centrilobular hypertrophy
May cause changes in haematological parameters

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: H317
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

TRANSLATIONS

Language

Name

English

bensulfuron-methyl

French

bensulfuron-methyle

German

Bensulfuron-methyl

Danish

bensulfuron-methyl

Italian

bensulfuron-metile

Spanish

bensulfuron-metil

Greek

Polish

bensulfuron metylowy

Swedish

Hungarian

benszulforon-metil

Dutch

Norwegian

Record last updated:	31/10/2024
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