Diethofencarb (Ref: S 1605)

Diethofencarb (Ref: S 1605)	Last updated: 25/02/2026
(Also known as: isopropyl-3,4-diethoxycarbanilate )

SUMMARY

Diethofencarb is a carbamate fungicide. It has a moderate aqueous solubility and is volatile. Based on its chemical properties, it is not expected to leach to groundwater. It is not persistent in soils but can be in water in some circumstances. It has a low mammalian toxicity. However, exposure may damage reproduction and/or development. Diethofencarb is also a recognised irritant. It is moderately toxic to most aquatic organisms, honeybees and earthworms.

Hazard alerts

The following Pesticide Hazard Tricolour (PHT) 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. The alerts for Highly Hazardous Pesticides (HHPs) are based on applying the FAO/WHO (Type 1) and the PAN (Type II) criteria to PPDB data. Further details on the HHP indicators are given in the tables below. Neither the PHT nor the HHP hazard alerts take account of usage patterns or exposure, thus they do not represent risk.

PHT: Environmental fate	PHT: Ecotoxicity	PHT: Human health	Highly Hazardous Pesticide
Environmental fate Moderate alert: Drainflow: Moderately mobile	Ecotoxicity Moderate alert: Birds chronic ecotoxicity: Moderate; Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate	Human health High alert: Reproduction/development effects

GENERAL INFORMATION

Description

A carbamate fungicide with strong activity against botrytis.

Example pests controlled

Botrytis cinerea and benzimidazole-resistant strains of Botryis spp.

Example applications

Apples; Pears; Ornamentals

Efficacy & activity

GB regulatory status

GB COPR regulatory status

Not approved

Date COPR inclusion expires

Withdrawn

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

France

Date EC 1107/2009 inclusion expires

Expired

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

Japan

Chemical structure

Isomerism

None

Chemical formula

C₁₄H₂₁NO₄

Canonical SMILES

CCOC1=C(C=C(C=C1)NC(=O)OC(C)C)OCC

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

LNJNFVJKDJYTEU-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C14H21NO4/c1-5-17-12-8-7-11(9-13(12)18-6-2)15-14(16)19-10(3)4/h7-10H,5-6H2,1-4H3,(H,15,16)

2D structure diagram/image available?

Yes

General status

Pesticide type

Fungicide

Substance groups

Carbamate fungicide; Carbanilate fungicide

Minimum active substance purity

970 g kg⁻¹

Known relevant impurities

EU dossier - toluene <1 g kg⁻¹

Substance origin

Synthetic

Mode of action

Systemic with protective and curative action. Inhibition of mitosis and cell division (Beta-tubulin assembly in mitosis).

CAS RN

87130-20-9

EC number

403-870-3

CIPAC number

513

US EPA chemical code

PubChem CID

91742

CLP index number

No data found

Molecular mass

267.32

PIN (Preferred Identification Name)

propan-2-yl (3,4-diethoxyphenyl)carbamate

IUPAC name

isopropyl 3,4-diethoxycarbanilate

CAS name

1-methylethyl (3,4-diethoxyphenyl)carbamate

Global Governance status: Listed (✓) under

UK Poisons List Order 1972	Rotterdam Convention	Montreal Protocol
XNo The Poisons List Order 1972	XNo Rotterdam Convention	XNo Montreal Protocol
Stockholm Convention	OSPAR	EU Water Framework Directive
XNo Stockholm Convention	XNo OSPAR	XNo EU Water Framework Directive

Relevant Environmental Water Quality Standards

Forever chemical

Highly Hazardous Pesticide (HHP)

Type I

Type II

Other status information

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 to pale pink crystalline solid

Commercial

Property

Value

Availability status

Current

Introduction & key dates

1986, introduced

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

Synthelor France
ABCR GmbH Germany
Fluorochem Ltd.

Example products using this active

Sumico
Powmyl 25WP

Formulation and application details

Usually formulated into suspension concentrates or wettable powders

Commercial production

Diethofencarb is commercially produced through the synthesis of its active compound, isopropyl 3,4-diethoxycarbanilate. The process typically involves the reaction of 3,4-diethoxyaniline with isopropyl chloroformate in the presence of a base such as triethylamine, which facilitates the formation of the carbamate linkage. This reaction is carried out in an organic solvent under controlled temperature and pH conditions to ensure high yield and purity.

Impact on climate of production and use

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C at pH 7 (mg l⁻¹)

27.64

Moderate

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

207400

Acetone

106100

Methanol

29900

Xylene

140400

Ethyl acetate

Melting point (°C)

98.3

Boiling point (°C)

272

Degradation point (°C)

Not highly flammable

Flashpoint (°C)

140

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

7.76 X 10⁰²

Calculated

Log P

2.89

Moderate

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.19

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

9.94 X 10^-03

at 25 °C

Low volatility

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

9.12 X 10^-05

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

24 hr

Volatilisation is not considered critical for air pollution

From soil surface

24 hr

Volatilisation is not considered critical for air pollution

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

Acid media: 207.7nm = 39000, 243.1nm = 16000, 286.8nm = 3600
Neutral media: 207.1nm = 39000, 243.3nm = 15000, 287nm = 3500
Basic media: 207.3nm = 39000, 243.1nm = 16000, 286.8nm = 3600

Surface tension (mN m⁻¹)

68.8

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

5.4

Non-persistent

DT₅₀ (lab at 20 °C)

4.6

Non-persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

32.8

Moderately persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 1.0-121.3 days; General literature DT₅₀: 1.5-9.2 days (R3)

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

2.6

Note

Published literature RL₅₀ range 2.0-3.1 days, 2 field crops, n=2

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Slow

Note

Natural summer sunlight

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

Value

Stable

Note

Stable at pH 3-9 at 25 °C

Water-sediment DT₅₀ (days)

24.9

Fast

Water phase only DT₅₀ (days)

9.8

Moderately 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)

5.7

Moderately mobile

K_foc (mL g⁻¹)

224

¹/_n

0.84

Notes and range

EU dossier K_f 0.02-15.98 mL g⁻¹, K_foc range 33-505 mL g⁻¹, ¹/_n range 0.410-0.953, Soils=14

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.09

Calculated

Low leachability

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

Value

3.49 X 10^-03

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

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

1.45

Calculated using the Atkinson method. EU trigger for long-range transport is DT₅₀ in air <2 days.

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

330

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

isopropyl 4,5-diethoxy-2-nitrocarbanilate

Major fraction

0.289

isopropyl 3-ethoxy-4-hydroxycarbanilate (Ref: 4-OH-DFC)

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

isopropyl 3-ethoxy-4-hydroxycarbanilate

4-OH-DFC

Animal; Surface water; Sediment

isopropylcarbamate

IPC

Surface water; Sediment

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 5000

Rat

Low

Mammals - Short Term Oral NOAEL (mg kg⁻¹ bw d⁻¹)

Mammals - Long Term (Chronic) Oral NOAEL (mg kg⁻¹ bw d⁻¹)

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2250

Anas platyrhynchos

Low

Birds - Short term dietary LC₅₀ (mg kg⁻¹ bw d⁻¹)

> 1629

Anas platyrhynchos

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

78.7

Anas platyrhynchos

Moderate

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

> 500

Eisenia foetida corr

Moderate

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

Soil micro-organisms

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

Dose: 7 mg kg⁻¹ soil

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

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)

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, Std lab test

> 1500

Aphidius rhopalosiphi

Low

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹, Std lab test

7.2

Typhlodromus pyri

Moderate

Beneficial insects (Ground beetles)

Beneficial insects (Butterflies)

Contact

Notes

Oral

Notes

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

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

> 10

Oncorhynchus mykiss

Moderate

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

0.072

Oncorhynchus mykiss Growth

Moderate

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

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

> 23

Daphnia magna

Moderate

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

0.032

Daphnia magna Reproduction

Moderate

Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (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)

3.8

Chironomus riparius

Moderate

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

Aquatic Plants (free-floating, fonds growth, fresh) - 7 day (mg l⁻¹)

Aquatic plants (rooted, growth rate, fresh) - 14 day (mg l⁻¹)

Algae - Acute (growth rate, fresh; mg l⁻¹) (72 hr ErC₅₀, Static)

14.0

Raphidocelis subcapitata

Low

Algae - Chronic (growth rate, fresh; mg l⁻¹)

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves

Regulatory Threshold Levels (RTLs)

Note: These RTLs have been calculated using the regulatory approach used in the European Union and based on ecotoxocity values in the PPDB.

Species group

RTL

Notes

Mammals

500

Worst case of acute and chronic mammals

Birds

15.74

Worst case of acute and chronic birds

Soil organisms

100

Worst case of acute and chronic earthworms

Terrestrial plants

No data

No data for non-target plants vegetative vigour and seedling emergence

Pollinators

Worst case of contact and oral honeybees

Arthropods

3.6

Worst case of parasitic wasps and predatory mites

Fish

0.0072

Worst case of temperate acute and chronic fish

Aquatic invertebrates

0.0032

Worst case of temperate acute and chronic aquatic invertebrates

Aquatic plants

1.4

Worst case of free-floating plants, rooted plants, acute and chronic algae

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 - Short Term Oral NOAEL (mg kg⁻¹ bw d⁻¹)

Mammals - Long Term (Chronic) Oral NOAEL (mg kg⁻¹ bw d⁻¹)

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

> 5000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 1.05

Rat 4 hr (whole body)

Other Mammal toxicity endpoints

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

0.43

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

None allocated

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

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

0.50

Dermal penetration studies (%)

0.7-6.0

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks identified

Occupational

No unacceptable risks identified

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 (hazard-based)

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

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, kidney and bladder toxicant
Causes serious eye irritation

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 6,1

CLP classification 2013

Health: H319
Environment: H412

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

UN2757

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

diethofencarb

French

diethofencarbe

German

Diethofencarb

Danish

diethofencarb

Italian

dietofencarb

Spanish

dietofencarb

Greek

Polish

dietofenkarb

Swedish

Hungarian

Dutch

diethofencarb

Norwegian

Record last updated:	25/02/2026
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

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