Myclobutanil hydrochloride

Myclobutanil hydrochloride	Last updated: 24/01/2023
(Not known by any other names)

SUMMARY

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
		Human health High alert: Endocrine distrupter

GENERAL INFORMATION

Description

A fungicide used to control Ascomycetes, Fungi Imperfecti and Basidiomycetes in a wide range of crops including table grapes

Example pests controlled

Powdery mildew; Dollar spot; Summer patch; Brown patch; Rusts; scab

Example applications

Perennial and annual crops; Turf; Landscape ornamentals; Fruit trees; Vines

Efficacy & activity

Availability status

Current

Introduction & key dates

1986, first reported; 1989, first marketed

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/05/2024

UK LERAP status

Check label - may vary with formulation

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

UK/Spain

Date EC 1107/2009 inclusion expires

Expired

EU Candidate for substitution (CfS)

Not applicable

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

Additional information

Also used in

Australia, USA, Asia, Africa

Chemical structure

Isomerism

A chiral molecule. The technical material is an isomeric equimolar mixture of the R- and S-forms.

Chemical formula

C₁₅H₁₇ClN₄O

Canonical SMILES

CC(CCC(CN1C=NC=N1)(C#N)C2=CC=C(C=C2)Cl)O

Isomeric SMILES

International Chemical Identifier key (InChIKey)

HIUOATAFAFIXAL-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C15H17ClN4O/c1-12(21)6-7-15(8-17,9-20-11-18-10-19-20)13-2-4-14(16)5-3-13/h2-5,10-12,21H,6-7,9H2,1H3

2D structure diagram/image available?

General status

Pesticide type

Fungicide

Substance groups

Triazole fungicide; Conazole fungicide

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Broad spectrum, systemic with protective, eradicative and curative action. Disrupts membrane function by inhibiting sterol biosynthesis.

CAS RN

116928-93-9

EC number

No data found

CIPAC number

442

US EPA chemical code

PubChem CID

189447

CLP index number

No data found

Molecular mass

304.77

PIN (Preferred Identification Name)

(RS)-2-(4-chlorophenyl)-5-hydroxy-2-(1,2,4-triazol-1-ylmethyl)hexanenitrile

IUPAC name

(RS)-2-(4-chlorophenyl)-5-hydroxy-2-(1,2,4-triazol-1-ylmethyl)hexanenitrile

CAS name

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

Related substances & organisms

myclobutanil

Formulations

Property

Value

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

AgriGuard
Dow AgroSciences
Landseer

Example products using this active

Formulation and application details

Often supplied as an oil suspension in water that is 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)

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

Log P

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

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

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

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

myclobutanil (Ref: RH 3866)

Major fraction

1,2,4-triazole (Ref: CGA 71019)

Major fraction

1H-1,2,4-triazol-1-ylacetic acid (Ref: CGA 142856)

Minor fraction

(3RS) 3-(4-chlorophenyl)-3-cyano-4-(1H-1,2,4-triazol-1-yl)butanoic acid

Minor fraction

(2RS) 2-(4-chlorophenyl)-5-oxo-2-(1H-1,2,4-triazol-1-ylmethyl)hexanenitrile

Minor fraction

Known groundwater metabolites

Metabolite

EC SANCO/221/2000 relevancy

ADI (mg kg⁻¹ bodyweight day⁻¹)

WHO drinking water guidance value (μg L⁻¹)

(3RS) 3-(4-chlorophenyl)-3-cyano-4-(1H-1,2,4-triazol-1-yl)butanoic acid

Not relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

(2RS,5RS) 2-(4-chlorophenyl)-5-hydroxy-2-(1H-1,2,4-triazol-1-ylmethyl)hexanenitrile (Ref: RH-9090)

Animal; Plant

(2RS) 2-(4-chlorophenyl)-5-oxo-2-(1H-1,2,4-triazol-1-ylmethyl)hexanenitrile (Ref: RH-9089)

Animal; Plant

(3RS) 3-(4-chlorophenyl)-3-cyano-4-(1H-1,2,4-triazol-1-yl)butanoic acid

Animal; Plant

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

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)

Birds - Short term dietary (LC₅₀/LD₅₀)

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

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

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

Soil micro-organisms

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

Honeybees (Apis 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)

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

Chronic

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)

Beneficial insects (Predatory mites)

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Fish - Chronic 21 day NOEC (mg l⁻¹)

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

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)

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

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

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)

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

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

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

0.025

Rat SF=100 as myclobutanil

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

0.31

Rat SF=100 as myclobutanil

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

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

0.03

as myclobutanil

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders identified

Occupational

No unacceptable risks to operators or other workers identified

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

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

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

Liver toxicant
Endocrine issues - Weak estrogen and androgen inhibition

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Code is usually 9
Not expected to autoignite; Not highly flammable

CLP classification 2013

Health: H302, H319, H361d
Environment: H411

WHO Classification

II (Moderately hazardous)

UN Number

Usually 3082

Waste disposal & packaging

Packaging Group III (minor danger)

TRANSLATIONS

Language

Name

English

myclobutanil hydrochloride

French

German

Danish

Italian

Spanish

Greek

Polish

Swedish

Hungarian

Dutch

Record last updated:	24/01/2023
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