Proquinazid (Ref: DPX KQ926)

Proquinazid (Ref: DPX KQ926)	Last updated: 04/06/2025
(Also known as: IN KQ926)

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
Environmental fate Moderate alert: Potential for particle bound transport: Medium	Ecotoxicity High alert: Birds chronic ecotoxicity: High; Fish chronic ecotoxicity: High; Daphnia chronic ecotoxicity: High	Human health High alert: Reproduction/development effects Warning: Significant data are missing

GENERAL INFORMATION

Description

A fungicide with the potential to control powdery mildew in a range of crops including cereals

Example pests controlled

Powdery mildew; Septoria leaf blotch; Glume blotch; Yellow rust; Brown rust; Eyespot; Ear disease complex

Example applications

Cereals including wheat, barley, oats, rye, triticale; Grapes

Efficacy & activity

Wheat/Mildew=High; Mildew=Moderate for protection, Low for eradication

Availability status

Current

Introduction & key dates

2005, introduced

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/07/2027

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

Sweden/Lithuania

Date EC 1107/2009 inclusion expires

15/05/2026

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

Morocco

Chemical structure

Isomerism

None

Chemical formula

C₁₄H₁₇IN₂O₂

Canonical SMILES

CCCN1C(=O)C2=C(C=CC(=C2)I)N=C1OCCC

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

FLVBXVXXXMLMOX-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C14H17IN2O2/c1-3-7-17-13(18)11-9-10(15)5-6-12(11)16-14(17)19-8-4-2/h5-6,9H,3-4,7-8H2,1-2H3

2D structure diagram/image available?

Yes

General status

Pesticide type

Fungicide

Substance groups

Quinazoline compound; Organoiodide compound

Minimum active substance purity

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Preventative and curative activity. Translocates and inhibits appressoria development stopping infections. Signal transduction

CAS RN

189278-12-4

EC number

606-168-7

CIPAC number

764

US EPA chemical code

044502

PubChem CID

11057771

CLP index number

616-211-00-1

Molecular mass

372.21

PIN (Preferred Identification Name)

IUPAC name

6-iodo-2-propoxy-3-propylquinazolin-4(3H)-one

CAS name

6-iodo-2-propoxy-3-propyl-4(3H)-quinazolinone

Other status information

PAN listed Highly Hazardous Chemical

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 at 99.2% purity

Formulations

Property

Value

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

DuPont

Example products using this active

Justice
Talius
Talendo

Formulation and application details

Often supplied as an emulsifiable concentrate 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)

0.93

at 25 °C

Low

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

250000

Acetone

250000

Dichloromethane

250000

Ethyl acetate

136000

Methanol

Melting point (°C)

61.5

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

367

Flashpoint (°C)

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

3.16 X 10⁰⁵

Calculated

Log P

5.5

at 25 °C

High

Fat solubility of residues

Solubility

Soluble

Data type

Regulatory data - observed in metabolism and farm animal feeding studies

Density (g ml⁻¹)

1.57

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.09

Low volatility

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

3.00 X 10^-02

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

14.4

24 hr

Volatilisation is not considered critical for air pollution

From soil surface

0.4

24 hr

Volatilisation is not considered critical for air pollution

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

Neutral, acid & basic media: 270nm = 16000, 325nm = 300

Surface tension (mN m⁻¹)

73.9

at 19.8 °C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

74.0

Moderately persistent

DT₅₀ (lab at 20 °C)

74.0

Moderately persistent

DT₅₀ (field)

23.4

Non-persistent

DT₉₀ (lab at 20 °C)

531.8

Very persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU 2022 dossier lab studies DT₅₀ range 21.6-228 days (normalised), DT₉₀ (measured) range 129-1140 days, Soils=4; Field studies DT₅₀ range 0.003-35,3 days, DT₉₀ range 16.5-200 days, European soils; Soils=8

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

1.0

Note

Published literature RL₅₀ range 0.77-1.26 days, Grapes, various matrices, n=2

Aqueous photolysis DT₅₀ (days) at pH 7

Value

0.03

Fast

Note

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

Value

Stable

Note

Stable pH 4 to pH 9 at 20 °C

Water-sediment DT₅₀ (days)

68.2

Moderately fast

Water phase only DT₅₀ (days)

0.78

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

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

185.6

Non-mobile

K_foc (mL g⁻¹)

13073

¹/_n

0.939

Notes and range

EU 2022 dossier K_f range 105.8-330.0 mL g⁻¹, K_foc range 8850-17636 mL g⁻¹, ¹/_n range 0.911-0.992, Soils=4

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

-0.16

Calculated

Low leachability

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

Value

5.35 X 10^-03

Calculated

Note

Estimated concentrations of chemicals with Koc values greater than 9995 ml g⁻¹ are beyond the scope of the regression data used in SCI-GROW development. If there are concerns for such chemicals, a higher tier groundwater exposure assessment should be considered, regardless of the concentration returned by SCI-GROW

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Non-mobile

Calculated

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

4.0

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)

813

Whole fish

Threshold for concern

CT₅₀ (days)

Not available

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

2-propoxy-3-propylquinazolin-4(3H)-one (Ref: IN MM671)

Major fraction

0.653

Toxicologically relevant

6-iodo-3-propylquinazoline-2,4(1H,3H)-dione (Ref: IN MM986)

Major fraction

0.328

3-propylquinazoline-2,4(1H,3H)-dione (Ref: IN MM991)

Major fraction

0.134

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Ref: IN-MU210

Plant; Animal (Urine); Rat

Ref: IN-MY341

Plant

Ref: IN-MY340

Plant; Poultry (Eggs)

Ref: IN-MM991

a = Plant; b = Water (Hydrolysis, Photolysis); Sediment

Ref: IN-NA251

Animal; Poultry (Eggs)

Ref: IN-NA252

Animal

Ref: IN-MW398

Poultry (Eggs)

Ref: IN-MW397

Poultry (Eggs)

Ref: IN-MT884

Water (Photolysis, Hydrolysis)

Ref: IN-NB673

Rat (Faeces, Urine)

Ref: IN-MU715

Rat (Faeces, Urine)

Ref: IN-GJ515

Rat (Faeces, Urine)

Ref: IN-MW977

Plant

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 4846

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

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

> 35

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2250

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

1371 mg kg bw⁻¹ day⁻¹

Colinus virginianus

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

7.78

Colinus virginianus NOEC

High

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

> 1000

Eisenia foetida

Low

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

25.45

Eisenia foetida 56 day corr

Moderate

Soil micro-organisms

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

Dose: 50 mg kg⁻¹ soil

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

308.6

Folsomia candida

Non-target plants

Honeybees (Apis spp.)

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

> 197

Apis mellifera

Low

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

> 125

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)

Beneficial insects (Parasitic wasps) as Mortality LR₅₀ g ha⁻¹

131.4

Aphidius rhopalosiphi

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

47.85

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)

0.349

Oncorhynchus mykiss

Moderate

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

0.003

Oncorhynchus mykiss technical material

High

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

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

0.287

Daphnia magna

Moderate

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

0.0018

Daphnia magna technical material

High

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

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

0.11

Americamysis bahia

Moderate

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

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

0.456

Chironomus riparius

Moderate

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

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

> 0.2

Lemna gibba

Moderate

Aquatic plants (rooted, growth) - Acute 14 day EC₅₀, biomass (mg l⁻¹)

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

0.684

Pseudokirchneriella subcapitata

Moderate

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

Mesocosm study data

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)

> 4846

Rat

Low

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

5000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 5.2

Rat 4 hr (nose only; dust/aerosol)

Other Mammal toxicity endpoints

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

0.012

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

0.19

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

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

0.02

Dermal penetration studies (%)

0.86-6.5%

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders identified

Occupational

Risk of exposure acceptable under label recommendations for use for personal protection clothing and equipment

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; Calc MAC=30.0 µg l⁻¹

Mammalian dose elimination route and rate

Eliminated via faeces (31-43%) and urine (43-56%) with 85-88% lose of dose within 48 hr

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

General human health issues

Formulation may be eye irritant
Possible liver and thyroid toxicant
May cause hormonal changes
Some published evidence to suggest possible human carcinogen; CLP data - suspected carcinogen

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 9
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H351
Environment: H400, H410

WHO Classification

Not listed (Not listed)

UN Number

UN3077

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

Stable and non-reactive under normal conditions of use, storage and transport

TRANSLATIONS

Language

Name

English

proquinazid

French

proquinazid technique

German

Proquinazid

Danish

proquinazid

Italian

proquinazid

Spanish

proquinazid

Greek

Polish

proquinazid

Swedish

Hungarian

Dutch

Norwegian

prokvinazid

Record last updated:	04/06/2025
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