(R)-hexaconazole

(R)-hexaconazole	Last updated: 13/10/2023
(Also known as: (-) hexaconazole)

SUMMARY

Little data is available for this specific isomer but is available for the isomer mixture. Hexaconazole is a fungicide used to control powdery mildew, scabs and rusts. It has a low aqueous solubility and a low viscosity. It tends to be environmentally persistent in both soil and aquatic systems. It is moderately toxic to birds, fish, aquatic invertebrates, algae and earthworms but has a low toxicity to honeybees. It has a low mammalian toxicity and no information on other health issues has been identified although it may be a skin and eye irritant.

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
	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate	Human health High alert: Endocrine disrupter

GENERAL INFORMATION

Description

An isomer of the conazole (imidazole) fungicide used to control both seed-borne and soil-borne diseases especially Ascomycetes and Basidiomycetes spp.

Example pests controlled

Powdery mildew, Scabs, Rusts

Example applications

Vines; Apples; Pears,; Bananas; Vegetables; Some small grain cereals

Efficacy & activity

Availability status

Current

Introduction & key dates

1986

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Not applicable

UK LERAP status

No UK approval for use

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

Italy

Date EC 1107/2009 inclusion expires

Not applicable

EU Candidate for substitution (CfS)

Not applicable

Listed in EU database

Yes (as hexaconazole)

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

Chemical structure

Isomerism

(R)-hexaconazole is the R-isomer of chiral hexaconazole

Chemical formula

C₁₄H₁₇Cl₂N₃O

Canonical SMILES

CCCCC(CN1C=NC=N1)(C2=C(C=C(C=C2)Cl)Cl)O

Isomeric SMILES

CCCC[C@](CN1C=NC=N1)(C2=C(C=C(C=C2)Cl)Cl)O

International Chemical Identifier key (InChIKey)

STMIIPIFODONDC-AWEZNQCLSA-N

International Chemical Identifier (InChI)

InChI=1S/C14H17Cl2N3O/c1-2-3-6-14(20,8-19-10-17-9-18-19)12-5-4-11(15)7-13(12)16/h4-5,7,9-10,20H,2-3,6,8H2,1H3/t14-/m0/s1

2D structure diagram/image available?

Yes

General status

Pesticide type

Fungicide, Other substance

Other constituent type

Wood preservative, Isomer of hexaconazole

Substance groups

Conazole fungicide

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Broad spectrum, systemic with protective and curative action. Disrupts membrane function. Sterol biosynthesis inhibitor.

CAS RN

221627-81-2

EC number

No data found

CIPAC number

465

US EPA chemical code

128925

PubChem CID

37888330

CLP index number

613-171-00-7

Molecular mass

314.21

PIN (Preferred Identification Name)

IUPAC name

(R)-2-(2,4-dichlorophenyl)-1-(1H-1,2,4-triazol-1-yl)hexan-2-ol

CAS name

α-butyl-α-(2,4-dichlorophenyl)-1H-1,2,4-triazole-1-ethanol

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

White crystalline solid

Related substances & organisms

hexaconazole

(S)-hexaconazole

Formulations

Property

Value

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

AgroCare
FCC
Syngenta

Example products using this active

Passport
Manage
Anvil
Planete Aster

Formulation and application details

Available in a variety of formulations including oil miscible liquids, soluble grains and suspension concentrates.

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

3.9

Note

Published literature data range 2.8-5.5 days, 4 field & glasshouse crops, various matrices, n=4

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 metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

2189

Rat as the isomer mix

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)

> 4000

Anas platyrhynchos as isomer mix

Low

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)

3.4

Oncorhynchus mykiss as the isomer mix

Moderate

Fish - Chronic 21 day NOEC (mg l⁻¹)

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

> 2.9

Daphnia magna as the isomer mix

Moderate

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)

2189

Rat as the isomer mix

Low

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

2000

Rat as the isomer mix

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

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

0.005

as hexaconazole

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

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

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

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

Occupational

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

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

; ; ; ;

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

US EPA - possible human carcinogen
Endocrine issues - Inhibition of aromatase activity, decrease of the estrogens production

Handling issues

Property

Value and interpretation

General

No information available

CLP classification 2013

Health: H302, H317
Environment: H411

WHO Classification

III (Slightly hazardous)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

(R)-hexaconazole

French

(R)-hexaconazole

German

(R)-Hexaconazol

Danish

(R)-hexaconazol

Italian

(R)-esaconozolo

Spanish

(R)-hexaconazol

Greek

Polish

(R)-heksakonazol

Swedish

Hungarian

(R)-hexakonazol

Dutch

Norwegian

Record last updated:	13/10/2023
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