Bixafen

Bixafen	Last updated: 31/03/2021
(Not known by any other names)

GENERAL INFORMATION

Description

A novel pyrazole fungicide for use in cereals for key stem and leaf disease control including strobilurin-resistant septoria

Example pests controlled

Septoria leaf blotch; Ear blotch; Eyespot; Glume blotch; Fusarium ear blight; Sooty moulds; Rusts

Example applications

Cereals including wheat, rye, triticale, barley, oats

Efficacy & activity

Availability status

Current

Introduction & key dates

2006

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

30/09/2026

UK LERAP status

Yes - check label

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Date EC 1107/2009 inclusion expires

30/09/2023

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

Chemical structure

Isomerism

Chemical formula

C₁₈H₁₂Cl₂F₃N₃O

Canonical SMILES

CN1C=C(C(=N1)C(F)F)C(=O)NC2=C(C=C(C=C2)F)C3=CC(=C(C=C3)Cl)Cl

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

LDLMOOXUCMHBMZ-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C18H12Cl2F3N3O/c1-26-8-12(16(25-26)17(22)23)18(27)24-15-5-3-10(21)7-11(15)9-2-4-13(19)14(20)6-9/h2-8,17H,1H3,(H,24,27)/f/h24H

2D structure diagram/image available?

Yes

General status

Pesticide type

Fungicide

Substance group

Pyrazolium

Minimum active substance purity

950 g/Kg

Known relevant impurities

EU dosssier - none declared

Substance origin

Synthetic

Mode of action

Succinate DeHydrogenase Inhibitor.

CAS RN

581809-46-3

EC number

CIPAC number

819

US EPA chemical code

PubChem CID

11434448

Molecular mass

414.21

PIN (Preferred Identification Name)

N-(3',4'-dichloro-5-fluoro[1,1'-biphenyl]-2-yl)-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxamide

IUPAC name

N-(3',4'-dichloro-5-fluorobiphenyl-2-yl)-3-(difluoromethyl)-1-methylpyrazole-4-carboxamide

CAS name

N-(3',4'-dichloro-5-fluoro[1,1'-biphenyl]-2-yl)-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxamide

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Classification (HRAC)

Not applicable

Herbicide Resistance Classification (WSSA)

Not applicable

Insecticide Resistance Classification (IRAC)

Not applicable

Fungicide Resistance Classification (FRAC)

Examples of recorded resistance

Physical state

White powder

Related substances & organisms

prothioconazole

Formulations

Property

Value

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

Bixafen EC 125

Example products using this active

Bayer CropScience

Formulation and application details

Usually supplied as an emulsifiable concentrate

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.49

Low

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

250000

Acetone

102000

Dichloromethane

32000

Methanol

16000

Toluene

Melting point (°C)

146.6

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

250

Flashpoint (°C)

Not expected to self ignite; Not highly flammable

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

2.00 X 10⁰³

Calculated

Log P

3.3

at 40 °C

High

Bulk density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

4.6 X 10^-05

Low volatility

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

3.89 X 10^-05

Non-volatile

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

210nm=42825; 290nm=4000

Surface tension (mN m⁻¹)

70.7

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

500

Very persistent

DT₅₀ (lab at 20 °C)

500

Very persistent

DT₅₀ (field)

254

Persistent

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

>1000

DT₅₀ modelling endpoint

Note

EU dossier Lab studies DT₅₀ estimated >1year; Field studies DT₅₀ range 30.6->1235 days, DT₉₀ estimated >1000 days

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

Stable

Note

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

Value

Stable

Note

Stable at pH 5, 7 & 9 at 50 °C

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Slow

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

K_oc

Notes and range

Freundlich

K_f

62.5

Slightly mobile

K_foc

3869

¹/_n

0.877

Notes and range

EU dossier K_f range 40.5-102.7 mL g⁻¹; K_foc range 2920-4974 mL g⁻¹; ¹/_n range0.857-0.855, soils =5

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

0.99

Calculated

Low leachability

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

Value

2.05 X 10^-02

Calculated

Note

Potential for particle bound transport index

High

Calculated

Potential for loss via drain flow

Slightly mobile

Calculated

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

bixafen pyrazole-4-carboxamide

Bixafen metabolite M43

Rat (Urinary); Plant

bixafen desmethyl pyrazole-4-carboxamide

Bixafen metabolite M42

Rat (Urinary); Soil

N-(3,4-dichloro-5-fluorobiphenyl-2-yl)-3-(difluoromethyl)-1H-pyrazole-4-carboxamide

Bifafen metabolite M21; BYF 00587-desmethyl; desmethyl bixafen

Plant; Animal; Rat

BYF 00587-hydroxy-glycoside-sulfate

Bixafen metabolite M20

Plant

BYF 00598-desmethyl-N-O-glucuronide

Bixafen metabolite M22

BYF 00587-desmethyl-pyrazole-4-carboxylic acid (tautomer 1 & 2)

Bixafen metabolite M44

Plant; Groundwater

BYF 00587-pyrazolone-4-carboxylic acid

Bixafen metabolite M47

Plant

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

695

Whole fish

Threshold for concern

CT₅₀ (days)

1.33

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)

169.2

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 1159 mg/Kg BW/day

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

24.5

Colinius virginianus

Moderate

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

0.095

Oncorhynchus mykiss

High

Fish - Chronic 21 day NOEC (mg l⁻¹)

0.0046

Pimephales promelas 33 day

High

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

1.2

Daphnia magna

Moderate

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

0.05

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)

0.0156

Chironomus riparius

Moderate

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

20.0

Chironomus riparius

Moderate

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

Non-target plants

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

0.097

Pseudokirchneriella subcapitata

Moderate

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)

> 121.4

Apis mellifera

Low

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

> 100

Apis mellifera

Low

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

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 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)

100

Eisenia foetida

Moderate

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

7.74

Folsomia candida

Other arthropod (1)

LR₅₀ g ha⁻¹

116

Typhlodromus pyri

% Effect

Other arthropod (2)

LR₅₀ g ha⁻¹

35.5

A5 Aphidius rhopalsiphi
-

% 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)

5000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 5.38

Rat 4 hr (nose only)

Other Mammal toxicity endpoints

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

0.02

Rat SF=100

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

0.2

Rat SF=100

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

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

0.13

Rat SF=100

Dermal penetration studies (%)

0.76-4.1

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Acceptable for intended uses

Occupational

Acceptable for intended uses

MRLs

European

EU MRL pesticide database

Notes

UK MRL levels for some commodities subject to change in late 2021

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 thyroid and liver 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: R50/53

EC Safety Classification

WHO Classification

NL (Not listed)

UN Number

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

bixafen

French

German

Danish

Italian

Spanish

Greek

Polish

Swedish

Hungarian

Dutch

Record last updated:	31/03/2021
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