Azoxystrobin (Ref: ICI 5504)

Azoxystrobin (Ref: ICI 5504)	Last updated: 22/08/2024
(Also known as: azoxystrobine; ICI-A 5504; Icia 5504)

SUMMARY

Azoxystrobin is a broad-spectrum QoL fungicide. It has a low aqueous solubility, is non-volatile and may leach to groundwater under certain conditions. It may be persistent in soil and can also be persistent in water systems if conditions are right. It has a low mammalian toxicity but may bioaccumulate. It is a skin and eye irritant. It is moderately toxic to birds, most aquatic life, honeybees and earthworms.

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: Persistent; GUS: High leachability	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Bees acute oral ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate; Earthworms chronic ecotoxicity: Moderate	Human health Moderate alert: Mammals chronic toxicity: Moderate; Genotoxic; Reproduction/development effects

GENERAL INFORMATION

Description

A post-emergence broad spectrum strobilurin fungicide used mainly for cereals

Example pests controlled

Rusts; Powdery mildew; Black rot; Scab; Anthracnose; White mould; Peg rot; Early & late blight; Leaf spot; Rice blast; Botrytis

Example applications

Wheat; Fruit including grapes, citrus, strawberries, peaches; Sunflowers; Vegetables including onions, brassicas and curcubits; Potatoes; Cotton; Pecans; Canola; Soybeans; Peanuts; Tomato; Turf; Ornamentals

Efficacy & activity

Wheat/Midlew=Low; Wheat/Septoria=Low; Wheat/Rust=Moderate-High; Barley/Rhynchosporium=Low; Barley/Rust=Moderate; Barley/Net blotch=Low; Corn/Leaf blight=High; Corn/Rust=High; Corn/Eyespot=High; Soybean/Blight=High; Soybean/Anthracnose=High; Soybean/Brown spot=Moderate; Soybean/Leaf blight=Moderate; Soybean/Rust=High; Soybean/White mould=Low

Availability status

Current

Introduction & key dates

1992, introduced

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/12/2029

GB LERAP status

Check label - may vary with formulation

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Austria/Norway

Date EC 1107/2009 inclusion expires

31/12/2024

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, Iran, Egypt, Morocco

Chemical structure

Isomerism

E-form of an isomeric molecule

Chemical formula

C₂₂H₁₇N₃O₅

Canonical SMILES

COC=C(C1=CC=CC=C1OC2=NC=NC(=C2)OC3=CC=CC=C3C#N)C(=O)OC

Isomeric SMILES

CO/C=C(\C1=CC=CC=C1OC2=NC=NC(=C2)OC3=CC=CC=C3C#N)/C(=O)OC

International Chemical Identifier key (InChIKey)

WFDXOXNFNRHQEC-GHRIWEEISA-N

International Chemical Identifier (InChI)

InChI=1S/C22H17N3O5/c1-27-13-17(22(26)28-2)16-8-4-6-10-19(16)30-21-11-20(24-14-25-21)29-18-9-5-3-7-15(18)12-23/h3-11,13-14H,1-2H3/b17-13+

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
azoxystrobin	-

General status

Pesticide type

Fungicide

Substance groups

Strobilurin fungicide

Minimum active substance purity

965 g kg⁻¹

Known relevant impurities

EU dossier: Toluene

Substance origin

Synthetic

Mode of action

Systemic translaminar and protectant action having additional curative and eradicant properties. Respiration inhibitor (QoL fungicide).

CAS RN

131860-33-8

EC number

603-524-3

CIPAC number

571

US EPA chemical code

128810

PubChem CID

3034285

CLP index number

607-256-00-8

Molecular mass

403.4

PIN (Preferred Identification Name)

methyl (2E)-2-(2-{[6-(2-cyanophenoxy)pyrimidin-4-yl]oxy}phenyl)-3-methoxyprop-2-enoate

IUPAC name

methyl (E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate

CAS name

methyl (αE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)benzeneacetate

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Not applicable

Herbicide Resistance Class (WSSA MoA class)

Not applicable

Insecticide Resistance Class (IRAC MoA class)

Not applicable

Fungicide Resistance Class (FRAC MOA class)

Examples of recorded resistance

Physical state

Yellow to white coloured crystalline solid

Formulations

Property

Value

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

AgriGuard
Clayton
Syngenta
BOC Sciences
ADAMA Australia Pty Ltd

Example products using this active

Amistar
Amistar Opti
Amistar Pro
Olympus
Priori Xtra
Quadris
Abound
Ortiva
Affiance
Radial Opti
Mirador 625

Formulation and application details

Often supplied as a suspension concentrated diluted for spray application

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

6.7

Low

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

Hexane

20000

Methanol

55000

Toluene

86000

Acetone

Melting point (°C)

116

Boiling point (°C)

360

Degradation point (°C)

345

Flashpoint (°C)

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

3.16 X 10⁰²

Calculated

Log P

2.5

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data

Density (g ml⁻¹)

1.34

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

1.10 X 10^-07

Low volatility

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

7.40 X 10^-09

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

202.6nm = 60700, 242.7nm = 17800, 295nm = 302

Surface tension (mN m⁻¹)

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Moderately persistent

DT₅₀ (lab at 20 °C)

84.5

Moderately persistent

DT₅₀ (field)

180.7

Persistent

DT₉₀ (lab at 20 °C)

363.3

Persistent

DT₉₀ (field)

600.4

DT₅₀ modelling endpoint

Note

EU Dossier lab studies DT₅₀ range 35.2-248 days, DT₉₀ range 187-824 days; Field studies DT₅₀ range 120.9-261.9 days (actual), DT₉₀ range 401.7-869.9 days; Other sources: 72-164 days

Dissipation rate RL₅₀ (days) on plant matrix

Value

7.6

Note

Published literature RL₅₀ range 1.6-15.2 days, 3 field & undercover grown crops, various matrices, n=4

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

8.0

Note

Published literature RL₅₀ range 0.4-17.5 days, 15 field & undercover grown crops, various matrices, n=17

Aqueous photolysis DT₅₀ (days) at pH 7

Value

8.7

Moderately fast

Note

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

Value

Stable

Note

Not pH senstive, hydrolytically stable

Water-sediment DT₅₀ (days)

205

Slow

Water phase only DT₅₀ (days)

6.1

Moderately 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

[Grapefruit: No residue decay after 3 wks @ 2 DegC, 93% RH, followed by 5 wks @ 8 DegC, 85% RH, followed by 2 wks @ 20 DegC, 80% RH; Field study], [Lettuce: No residue decay observed after 21 days storage @ 4 DegC, dark conditions; Field study], [Pepper: No residue decay observed after 21 days storage @ 4 DegC, dark conditions; Field study]

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

8.93

Slightly mobile

K_oc (mL g⁻¹)

589

Notes and range

EU dossier K_d range 2.1-15.0 mL g⁻¹; K_oc range 304-739 mL g⁻¹, Soils=6; Other data sources: K_oc = 1590 mL g⁻¹ (DW3)

Freundlich

K_f (mL g⁻¹)

7.35

Moderately mobile

K_foc (mL g⁻¹)

423

¹/_n

0.85

Notes and range

EU dossier K_f range 1.5-15.0 mL g⁻¹, K_foc range 207-594 mL g⁻¹, ¹/_n range 0.82-0.90, Soils=6

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

3.10

Calculated

High leachability

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

Value

3.83 X 10^-01

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Slightly mobile

Calculated

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

2.7

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)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

No data

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

4-(2-cyanophenoxy)-6-hydroxypyrimidine (Ref: R401553)

Minor fraction

0.057

2-(6-(2-cyanophenoxy)pyrimidin-4-yloxy)benzoic acid (Ref: R402173)

Minor fraction

0.076

(E)-2-(2-(6-(2-cyanophenoxy)pyrimidin-4-yloxy)phenyl)-3-methoxyacrylic acid (Ref: R234886)

Major fractio

0.288

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)

(E)-2-(2-(6-(2-cyanophenoxy)pyrimidin-4-yloxy)phenyl)-3-methoxyacrylic acid (Ref: R234886)

Not relevant

0.017

102

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

4-{[6-(2-cyanophenoxy)pyrimidin-4-yl]oxy}-3-[(1E)-1,3-dimethoxy-3-oxoprop-1-en-2-yl]phenyl glucopyranuronic acid

Metabolite K1

Unknown

2-{[6-(2-cyanophenoxy)pyrimidin-4-yl]oxy}-x-hydroxybenzoic acid

Metabolite L9

Animal

2-(2-{[6-(2-cyanophenoxy)pyrimidin-4-yl]oxy}phenyl)-3-methoxypropanoic acid

Metabolite U5

Unknown

6-(2-cyanophenoxy)-3-glucosylpyrimidin-4-one (Ref: R405287)

Metabolite M42

Plant

methyl (2E)-2-(2-{[6-(2-cyanophenoxy)pyrimidin-4-yl]oxy}-x-hydroxyphenyl)-3-methoxyprop-2-enoate

Metabolite L1

Animal

glucosyl (E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxypropionate

Metabolite N1

Plant

glucosyl (2E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate

Metabolite N2

Plant

methyl (Z)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate (Ref: R230310)

Metabolite M09; Z-isomer of azoxystrobin

Plant

(2-{[6-(2-cyanophenoxy)pyrimidin-4-yl]oxy}phenyl)acetic acid

Metabolite M20

Animal

2-hydroxybenzonitrile

Metabolite M13

Unknown

(E)-2-(2-(6-(2-cyanophenoxy)pyrimidin-4-yloxy)phenyl)-3-methoxyacrylic acid (Ref: R234886)

Plant; Surface water; Sediment

glucosylmalonyl 2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxypropionate

Metabolite O2

Plant

glucosylmalonyl (2E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate

Metabolite O3

Plant

S-(2-cyano-x-hydroxyphenyl)cysteine

Metabolite L4

Animal

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

High

(ppm diet)

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

170

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 1179 mg kg⁻¹

Colinus virginianus

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

1200

Colinus virginianus

Low

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

283

Eisenia foetida

Moderate

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

3.0

Eisenia foetida

Moderate

Soil micro-organisms

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

Dose: 2.5 kg ha⁻¹

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

> 20

Lettuce Radish Wheat
Seedling emergence, ER₅₀
as mg kg⁻¹ soil

Honeybees (Apis spp.)

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

> 200

Apis mellifera

Low

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

> 25

Apis mellifera

Moderate

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

Chronic

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

> 1000

Aphidius rhopalosiphi

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

> 1500

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)

0.47

Oncorhynchus mykiss

Moderate

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

0.147

Pimephales promelas

Moderate

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

1.45

Danio rerio

Moderate

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

0.23

Daphnia magna

Moderate

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

0.044

Daphnia magna

Moderate

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

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

0.055

Americamysis bahia

High

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

0.210

Chironomus riparius

Moderate

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

0.8

Chironomus riparius

Moderate

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

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

3.2

Lemna gibba fronds

Moderate

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

0.36

Pseudokirchneriella subcapitata

Moderate

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

0.8

Unknown species

Moderate

Mesocosm study data

NOEAEC mg l⁻¹

0.010

Daphna Cladocera Copepoda

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)

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.69

Rat (particle size <2.0 um)

Other Mammal toxicity endpoints

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

0.2

Rat 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)

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

0.2

Rat SF=100

Dermal penetration studies (%)

0.3-0.5

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks identified

Occupational

No unacceptable risks identified

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

GB MRL amemendments as of Sept 2023 for mangoes, oil palms fruits, sugar beet roots and hops; Dec 2023 for celery and rhubarb

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

Minor effects on reproduction / development observed
Liver toxicant

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 6.1
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H331
Environment: H400, H410

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

UN2811

Waste disposal & packaging

Packaging Group II (moderate danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

azoxystrobin

French

azoxystrobine

German

Azoxystrobin

Danish

azoxystrobin

Italian

azoxystrobin

Spanish

azoxistrobina

Greek

azoxystrobin

Polish

azoksystrobina

Swedish

azoxystrobin

Hungarian

azoxistrobin

Dutch

azoxystrobin

Norwegian

azoksystrobin

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