Metsulfuron

Metsulfuron	Last updated: 12/01/2021
(Also known as: metsu 453)

GENERAL INFORMATION

Description

A herbicide used to control weeds mainly in cereals and land temporarily removed from production, used as the methyl variant. It is also be a pesticide transformation product.

Example pests controlled

Some annual grasses; Broad-leaved weeds

Example applications

Cereals; Land removed from production

Efficacy & activity

Availability status

Current

Introduction & key dates

1984

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/03/2026

UK LERAP status

Buffer probably required in UK - see product label

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Slovenia/Sweden

Date EC 1107/2009 inclusion expires

31/03/2023

EU Candidate for substitution (CfS)

Yes - two 'Persistent-Bioaccumulative-Toxic' criteria

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

Chemical structure

Isomerism

Chemical formula

C₁₃H₁₃N₅O₆S

Canonical SMILES

CC1=NC(=NC(=N1)OC)NC(=O)NS(=O)(=O)C2=CC=CC=C2C(=O)O

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

UWHURBUBIHUHSU-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C13H13N5O6S/c1-7-14-11(17-13(15-7)24-2)16-12(21)18-25(22,23)9-6-4-3-5-8(9)10(19)20/h3-6H,1-2H3,(H,19,20)(H2,14,15,16,17,18,21)

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide, Metabolite

Metabolite Type

Soil

Substance group

Sulfonylurea

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Selective, systemic with contact and residual action. Inhibits plant amino acid synthesis - acetohydroxyacid synthase AHAS

CAS RN

79510-48-8

EC number

CIPAC number

441

US EPA chemical code

PubChem CID

91730

Molecular mass

367.34

PIN (Preferred Identification Name)

2-{[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)carbamoyl]sulfamoyl}benzoic acid

IUPAC name

2-(4-methoxy-6-methyl-1,3,5-triazin-2-ylcarbamoylsulfamoyl)benzoic acid

CAS name

2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino]sulfonyl]benzoic acid

Other status information

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 solid

Related substances & organisms

metsulfuron-methyl

Can be a metabolite of:

Parent

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

metsulfuron-methyl

Soil

Formulations

Property

Value

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

Example products using this active

Formulation and application details

Normally used as the methyl variant.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

172

at 25 °C

Moderate

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

Melting point (°C)

Boiling point (°C)

Degradation point (°C)

Flashpoint (°C)

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

5.01 X 10⁰¹

Calculated

Log P

1.7

Low

Bulk density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

3.99 X 10^-08

at 25 °C

Low volatility

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

2.38 X 10^-11

at 25 °C

Non-volatile

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

Surface tension (mN m⁻¹)

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

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

Note

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

Value

Note

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

K_oc

Notes and range

Freundlich

K_f

K_foc

¹/_n

Notes and range

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

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

Value

Cannot be calculated

Note

Potential for particle bound transport index

Potential for loss via drain flow

Key metabolites

Metabolite

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

methyl 2-(aminosulfonyl)benzoate (Ref: IN-D5803)

Soil

0.170

Major fraction; Relevant

2-(aminosulfonyl) benzoic acid (Ref: IN-D5119)

Soil

0.100

Major fraction; Relevant

phenylurea (Ref: IN-B5685)

Soil

0.170

Major fraction; Relevant

1,2-benzisothiazol-3(2H)-one,1,1-dioxide (Ref: IN-00581)

Soil

0.470

Major fraction; Relevant

2-amino-4-methoxy-6-methyl-1,3,5-triazine (Ref: IN-A4098)

Soil

0.330

Major fraction; Relevant

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 5000

Rat

Low

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)

> 5000

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

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

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 150

Oncorhynchus mykiss as methyl variant

Low

Fish - Chronic 21 day NOEC (mg l⁻¹)

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

150

Daphnia magna as methyl variant

Low

Aquatic invertebrates - Chronic 21 day NOEC (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)

Non-target plants

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

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

Honeybees (Apis spp.)

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

> 25

as the methyl variant

Moderate

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

> 44.3

as the methyl variant

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)

> 1000

Eisenia foetida as methyl variant

Low

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

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Other arthropod (1)

LR₅₀ g ha⁻¹

% Effect

Other arthropod (2)

LR₅₀ g ha⁻¹

% Effect

Soil micro-organisms

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)

> 5000

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

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

0.22

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)

0.7

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

Occupational

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

; ; ; ;

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

No further information available

Handling issues

Property

Value and interpretation

General

No information available

CLP classification 2013

Environment: H400, H410

EC Risk Classification

N - Dangerous for the environment: R50, R53

EC Safety Classification

S60, S61

WHO Classification

NL (Not listed)

UN Number

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

metsulfuron

French

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Polish

Swedish

Hungarian

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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