Azimsulfuron

Azimsulfuron	Last updated: 12/01/2021
(Also known as: DPX A 8947; DPX 47)

SUMMARY

A sulfonylurea herbicide that is approved at EU level for use but is not approved in the UK. It is highly soluble in water, semi-volatile and, based on its physico-chemical properties, appears to have potential for leaching to groundwater. It is not expected to be persistent in the field but can be persistent in water systems. It has a low mammalian toxicity but has high potential for bioaccumulation. No adverse health effects have been identified. Azimsulfuron is modertaely toxic to algae, honeybees and eathworms but less so to birds and fish.

GENERAL INFORMATION

Description

A post-emergence pyrimidinylsulfonylurea herbicide for the control of a range of broad-leaved and sedge weeds in paddy fields and other crops

Example pests controlled

Cyperus spp.; Fimbristylis miliacea; Barnyard grass; Water plantain; Arrowhead; Dirty Dora; Spikerush; Starfruit; Alisma

Example applications

Paddy fields; Aquatic situations

Efficacy & activity

Availability status

Current

Introduction & key dates

1995

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Not applicable

UK LERAP status

Not applicable

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Spain/France

Date EC 1107/2009 inclusion expires

31/12/2021

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

None

Chemical formula

C₁₃H₁₆N₁₀O₅S

Canonical SMILES

CN1C(=C(C=N1)C2=NN(N=N2)C)S(=O)(=O)NC(=O)NC3=NC(=CC(=N3)OC)OC

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

MAHPNPYYQAIOJN-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C13H16N10O5S/c1-22-11(7(6-14-22)10-18-21-23(2)19-10)29(25,26)20-13(24)17-12-15-8(27-3)5-9(16-12)28-4/h5-6H,1-4H3,(H2,15,16,17,20,24)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
azimsulfuron	-

General status

Pesticide type

Herbicide

Substance group

Sulfonylurea

Minimum active substance purity

980 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Selective, absorbed by foliage. Inhibits plant amino acid synthesis - acetohydroxyacid synthase AHAS

CAS RN

120162-55-2

EC number

Not assigned

CIPAC number

584

US EPA chemical code

PubChem CID

86355

Molecular mass

424.40

PIN (Preferred Identification Name)

N-[(4,6-dimethoxypyrimidin-2-yl)carbamoyl]-1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulfonamide

IUPAC name

1-(4,6-dimethoxypyrimidin-2-yl)-3-[1-methyl-4-(2-methyl-2H-tetrazol-5-yl)pyrazol-5-ylsulfonyl]urea

CAS name

N-(((4,6-dimethoxy-2-pyrimidinyl)amino)carbonyl)-1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulfonamide

Other status information

Australian NOHSC List of Designated Hazardous Substances

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

Cyperus difformis, Echinochloa colona, Lindernia dubia

Physical state

White powdery solid

Formulations

Property

Value

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

Gulliver
Azimsulfuron 50WG
Segment

Example products using this active

DuPont

Formulation and application details

May be supplied as water-dispersible granules

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

1050

High

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

26400

Acetone

13000

Ethyl acetate

2100

Methanol

1800

Toluene

Melting point (°C)

170

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

180

Flashpoint (°C)

Not expected to self ignite; Not highly flammable

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

3.98 X 10^-02

Calculated

Log P

-1.4

at 25 °C

Low

Bulk density (g ml⁻¹)

1.12

Dissociation constant pKa) at 25 °C

3.6

Weak acid

Vapour pressure at 20 °C (mPa)

4.00 X 10^-06

Low volatility

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

5.00 X 10^-10

Non-volatile

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

242nm = 23014, 23988, 24099

Surface tension (mN m⁻¹)

68.1

at 24 °C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Unflooded soil

Moderately persistent

DT₅₀ (lab at 20 °C)

64.2

Unflooded soil

Moderately persistent

DT₅₀ (field)

3.5

Non-persistent

DT₉₀ (lab at 20 °C)

166

Unflooded soil

Persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 17.3-133 days & DT₉₀ range 66.6-529 days for non-flooded situations, DT₅₀ range 12.1-51.0 days & DT₉₀ range 58.7-169 day whole system; Other literature studies give field DT₅₀ 2-5 days; Australian registration dossier 18-134 days European soils (A5)

Dissipation rate RL₅₀ on plant matrix

Value

Note

Dissipation rate RL₅₀ on and in plant matrix

Value

3.3

Note

Rice, whole plant, n=1

Aqueous photolysis DT₅₀ (days) at pH 7

Value

164

Stable

Note

pH sensitive: 103 days at pH 5, 225 days at pH 9, all at 20 °C

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

Value

124

Persistent

Note

pH sensitive: 89 days at pH 5, 124 days at pH7, 132 days at pH 9 all at 26 °C

Water-sediment DT₅₀ (days)

112

Slow

Water phase only DT₅₀ (days)

44.5

Stable

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

1.14

Mobile

K_oc

73.8

Notes and range

EU dossier K_d range 0.69-1.65 mL g⁻¹, K_oc range 48-94 mL g⁻¹, Soils=4

Freundlich

K_f

1.11

Mobile

K_foc

68.6

¹/_n

0.93

Notes and range

EU dossier K_f range 0.75-1.31 mL g⁻¹, K_foc range 54-78 mL g⁻¹, ¹/_n range 0.88-0.98, Soils=4

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.18

Calculated

Low leachability

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

Value

2.77 X 10^-03

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Mobile

Calculated

Key metabolites

Metabolite

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulfonamide (Ref: IN-A8342)

Soil / Flooded soil

0.280 / 0.06

Major fraction, Relevant

1-amino-4,6-dimethoxypyrimidine (Ref: IN-J0290)

Soil / Flooded soil

0.24 / 0.03

Major fraction, Relevant

N-(((aminoiminomethyl)amino)carbonyl)-1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulphonamide (Ref: IN-KQ962)

Soil / Flooded soil

0.13 / 0.075

Major fraction, Relevant

N-((4-hydroxy-6-methoxypyrimidin-2-yl)amino)carbonyl)-1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulfonamide (Ref: IN-JJ999)

Soil / Flooded soil

0.02 / 0.13

Minor fraction, Relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

2-amino-6-methoxy-4-pyrimidinol (Ref: IN-H92350)

N-(4,6-dimethoxy-2-pyrimidinyl)-beta-D-glucopyranosylamine

N-glucosyl-J0290; glucosyl-J0290

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)

Rat 2 year

(ppm diet)

> 1000

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

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2250

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5620 mg kg feed⁻¹

Colinus virginianus

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

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

154

Oncorhynchus mykiss

Low

Fish - Chronic 21 day NOEC (mg l⁻¹)

6.3

Oncorhynchus mykiss

Moderate

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

378

Daphnia magna

Low

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

5.4

Daphnia magna

Moderate

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)

0.00062

Lemna gibba

High

Non-target plants

2.64

Onion
Seedling emergence, ER₅₀
as g product 50DF ha⁻¹

0.45

Sugarbeet
Vegetative vigour, ER₅₀
as g product 50DF ha⁻¹

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

0.011

Pseudokirchneriella subcapitata

Moderate

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

0.003

Selenastrum capricornutum

Moderate

Honeybees (Apis spp.)

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

> 25

Moderate

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

> 200

Low

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

Low

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

12.5

Eisenia foetida 56 days

Moderate

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Other arthropod (1)

LR₅₀ g ha⁻¹

54.3

> Mortality
Typhlodromus pyri

% Effect

2.1

Beneficial capacity [Dose: 0.027 g ha⁻¹)
Typhlodromus pyri

Other arthropod (2)

LR₅₀ g ha⁻¹

58.8

> Mortality
Aphidius rhopalosiphi

% Effect

22.6

Beneficial capacity [Dose: 0.029 g ha⁻¹)
Aphidius rhopalosiphi

Soil micro-organisms

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

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)

> 5.94

Rat 4 hr

Other Mammal toxicity endpoints

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

0.1

Rat SF=100

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

Not 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)

0.1

Rat SF=100

Dermal penetration studies (%)

100

default

Dangerous Substances Directive 76/464

Exposure Routes

Public

Negligible risk to bystanders for proposed uses

Occupational

Occupational exposure possible during product handling - PPE/PPC advised

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

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Possible pancreas toxicant
Possible liver and kidney toxicant

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising

CLP classification 2013

Environment: H400, H410

EC Risk Classification

N - Dangerous for the environment: R50, R53

EC Safety Classification

S61, R60

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

azimsulfuron

French

azimsulfuron

German

Azimsulfuron

Danish

azimsulfuron

Italian

azimsulfuron

Spanish

azimsulfuron

Greek

azimsulfuron

Polish

azymsulfuron

Swedish

Hungarian

Dutch

azimsulfuron

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