Hexaconazole is a fungicide used to control powdery mildew, scabs and rusts. It has a moderate 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.
Hazard 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. These hazard alerts do not take account of usage patterns or exposure, thus do not represent risk.
Environmental fate
Ecotoxicity
Human health
Environmental fate High alert: Persistent; Potential for particle bound transport: High
A 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
-
GB regulatory status
GB COPR regulatory status
Not approved
Date COPR inclusion expires
Not applicable
GB LERAP status
No UK approval for use as a plant protection agent
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)
-
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
Chemical structure
Isomerism
Hexaconazole exhibits stereoisomerism due to the presence of a chiral centre in its molecular structure. Specifically, it exists as two enantiomers: the (R)-hexaconazole and (S)-hexaconazole forms. The R-enantiomer exhibits the greatest fungicial activity.
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.
Commercial production
The production of hexaconazole involves a multi-step synthetic process that constructs its complex heterocyclic structure. It typically begins with the preparation of a substituted aromatic precursor such as m-dichlorobenzene or chloroacetyl chloride, which undergoes halogenation and alkylation reactions to introduce key functional groups. These intermediates are then reacted with reagents like pentyl chloride, dimethyl sulphide, and methyl iodide to build the 1,2,4-triazole ring central to hexaconazole’s fungicidal activity. A notable advancement in its synthesis is the one-pot method, which streamlines the process by combining steps such as mother liquor preparation, heat treatment, dissolution, and purification into a single reaction vessel, thereby improving efficiency and reducing production costs.
Impact on climate of production and use
Data for the amount of life cycle GHGs produced by hexaconazole production are not available in the public domain. However, whilst estimates vary, more general data suggests that between 11 and 30 kilograms of CO₂e is emitted per kilogram of fungicide produced.
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
18
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
Moderate
Solubility - In organic solvents at 20 °C (mg l⁻¹)
120000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Ethyl acetate
-
164000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Acetone
-
810
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Hexane
-
246000
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Methanol
-
Melting point (°C)
111
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Boiling point (°C)
-
-
-
Degradation point (°C)
-
-
-
Flashpoint (°C)
-
-
-
Octanol-water partition coefficient at pH 7, 20 °C
P
7.94 X 1003
Calculated
-
Log P
3.9
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
High
Fat solubility of residues
Solubility
Likely to be soluble
Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source
-
Data type
Based on chemical group
Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source
-
Density (g ml⁻¹)
1.29
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Dissociation constant pKa) at 25 °C
2.3
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
-
Strong acid
Vapour pressure at 20 °C (mPa)
0.018
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
3.33 X 10-04
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Non-volatile
Volatilisation as max % of applied dose lost
From plant surface
-
-
-
From soil surface
-
-
-
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)
122
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Persistent
DT₅₀ (lab at 20 °C)
-
-
-
DT₅₀ (field)
225
P3 P = Other non-EU, UK or US Governments and Regulators 3 = Unverified data of known source
Persistent
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
Sandy loam DT₅₀ ~ 10 months, clay loam ~ 5 months; General literature DT₅₀ range 49-200 days (R3)
Dissipation rate RL₅₀ (days) on plant matrix
Value
5.3
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
-
Note
Mango, n=1
Dissipation rate RL₅₀ (days) on and in plant matrix
Value
5.5
R4 R = Peer reviewed scientific publications 4 = Verified data
-
Note
Published literature RL₅₀ range 1.7-7.8 days, 7 field crops, various matrices, n=9
Aqueous photolysis DT₅₀ (days) at pH 7
Value
10
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Moderately fast
Note
-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7
Value
Stable
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Stable
Note
Not greatly sensitive to pH
Water-sediment DT₅₀ (days)
112
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Slow
Water phase only DT₅₀ (days)
112
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Stable
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
[Grapes: 6.7 days @ 25 DegC; 8.1 days @ 4 DegC; Field study]
Soil adsorption and mobility
Property
Value
Source; quality score; and other information
Interpretation
Linear
Kd (mL g⁻¹)
-
DW3 DW = Don Wauchope personal database for Pka data: Wauchope, R. D. and Edwards, J. Dissociation constants for pesticide active ingredients: a database and comparison with predicted values. Dataset is no longer available. 3 = Unverified data of known source
Slightly mobile
Koc (mL g⁻¹)
1040
Notes and range
-
Freundlich
Kf (mL g⁻¹)
-
-
-
Kfoc (mL g⁻¹)
-
1/n
-
Notes and range
-
pH sensitivity
-
Fate indices
Property
Value
Source; quality score; and other information
Interpretation
GUS leaching potential index
2.31
Calculated
Transition state
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
1.29 X 10-01
Calculated
-
Note
-
Potential for particle bound transport index
High
Calculated
-
Potential for loss via drain flow
Slightly mobile
Calculated
-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk
-
-
-
Bio-concentration factor
BCF (l kg⁻¹)
412
Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
Rat
Low
Mammals - Short term dietary NOEL
(mg kg⁻¹)
5
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
High
(ppm diet)
-
-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Birds - Acute LD₅₀ (mg kg⁻¹)
> 4000
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Anas platyrhynchos
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)
414
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Moderate
Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)
-
-
-
Soil micro-organisms
-
-
-
Collembola
Acute LC₅₀ (mg kg⁻¹)
-
-
-
Chronic NOEC (mg kg⁻¹)
-
-
-
Non-target plants
Vegetative vigour ER₅₀ (g ha⁻¹)
-
-
-
Seedling emergence ER₅₀ (g ha⁻¹)
-
-
-
Honeybees (Apis spp.)
Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
> 100
K3 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 3 = Unverified data of known source
Apis mellifera
Low
Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
> 100
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Apis mellifera
Low
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)
Harmless at dose 120 g ha⁻¹
AA2 AA = IOBC Database on classification of side effects to beneficial organisms, 2005 2 = Unverified data of unknown source
Chrysoperla carnea
-
Beneficial insects (Parasitic wasps)
-
-
-
Beneficial insects (Predatory mites)
Harmless at dose 120 g ha⁻¹
AA2 AA = IOBC Database on classification of side effects to beneficial organisms, 2005 2 = Unverified data of unknown source
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)
3.4
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Oncorhynchus mykiss
Moderate
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)
-
-
-
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
> 5.77
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
Rat
Low
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)
2000
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
-
Mammals - Inhalation LC₅₀ (mg l⁻¹)
5.9
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
-
Other Mammal toxicity endpoints
-
-
-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)
0.005
A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes
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
Environmental fate
Ecotoxicity
