Eugenol

Eugenol	Last updated: 25/08/2025
(Also known as: clove oil; essential clove oil; 5-allylguaiacol )

GENERAL INFORMATION

Description

A natural plant extract which exhibits insecticidal, fungicidal and anti-bacterial activity. At high concentrations it can also be used as a herbicide.

Examples of veterinary uses

Examples of species treated

Approval status

VMR 2013/2033 approval status (GB/UK)

EU Regulatory approval status

Chemical structure

Isomerism

Eugenol is isomeric existing in the o- and p-forms however it is p-eugenol form (4-allyl-2-methoxyphenol) rather than o-eugenol (2-allyl-6-methoxyphenol) that is normally referred to as eugenol

Chemical formula

C₁₀H₁₂O₂

Canonical SMILES

COC1=C(C=CC(=C1)CC=C)O

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

RRAFCDWBNXTKKO-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C10H12O2/c1-3-4-8-5-6-9(11)10(7-8)12-2/h3,5-7,11H,1,4H2,2H3

2D structure diagram/image available?

Yes

General status

Veterinary substance type

Other bioactivity & uses

Bactericide

Substance groups

Plant-derived substance

Minimum active substance purity

990 g kg⁻¹

Known relevant impurities

EU dossier - methyleugenol <1 g kg⁻¹

Substance origin

Natural

Mode of action

Prohibits the growth of both Gram-positive and Gram-negative bacteria and fungi. Strong insect repellent

Molecular targets

CAS RN

97-53-0

EC number

202-589-1

CIPAC number

967

US EPA chemical code

102701

PubChem CID

CLP index number

No data found

Therapeutic Class

ATCvet Code

Controlled Drug?

Regulation 37/2010 MRL Classification

Molecular mass

164.21

PIN (Preferred Identification Name)

IUPAC name

2-methoxy-4-(prop-2-en-1-yl)phenol

CAS name

phenol, 2-methoxy-4-(2-propen-1-yl)-

Forever chemical

Other status information

Highly phytotoxic; USEPA minimum risk pesticide; EU Low-risk active substance

Relevant Environmental Water Quality Standards

Physical state

Amber to light yellow liquid depending upon purity, with clove type odour

Related substances & organisms

clove oil

Commercial

Property

Value

Availability status

Current

Introduction & key dates

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

Xeda International
Farma Tech International Corp
Eden Research plc

Example products using this active

Bioxeda
Methyl Eugenol
Mevalone3AEY

Formulation and application details

Available in a variety of formulations including emulsifiable concentrates, drenches and hot fogs

Commercial production

Eugenol is produced commercially via extraction from natural sources and chemical synthesis. The most common approach is using steam distillation to extract eugenol from essential oils like clove oil, holy basil oil and cinnamon oil. The plant material is subjected to steam, which vaporizes the eugenol. The vapor is then condensed and collected. Alternatively, eugenol can be extracted using fractional distillation, solvent extraction, supercritical CO₂ extraction, microwave-assisted extraction or ultrasound-assisted extraction.

Impact on climate of production and use

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

1.78

Low

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

>250000

Ethyl actetate

>250000

Methanol

>250000

Acetone

>250000

1,20dichloroethane

Melting point (°C)

-40

Boiling point (°C)

254.7

Degradation point (°C)

Flashpoint (°C)

127

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

3.09 X 10⁰²

Calculated

Log P

2.49

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data based on LogP value

Density (g ml⁻¹)

1.06

Dissociation constant pKa) at 25 °C

10.27

Vapour pressure at 20 °C (mPa)

2700

Highly volatile. If applied directly to plants or soil, drift is a concern & mitigation is advisable

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

0.24

Moderately volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Acid pH 1.2: 201nm=37988, 222nm=6566, 281nm=2883
Neutral pH7.01: 200nm=39846, 226nm=6374, 281nm=2883
A;lkaline pH 11.6: 206nm=30461, 246nm=7816, 297nm=3780

Surface tension (mN m⁻¹)

36.6

Refractive Index

Environmental release

Degradation

Property

Value

Source; quality score; and other information

Interpretation

Soil degradation (days) (aerobic)

DT₅₀ (typical)

1.0

Non-persistent

DT₅₀ (lab at 20 °C)

1.0

Non-persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

2.4

Non-persistent

DT₉₀ (field)

Note

EU 2023 dossier Lab studies DT₅₀ (normalised) range 0.5 to <1.0 days, Soils=4

Manure DT₅₀ (days)

Aqueous photolysis DT₅₀ (days) at pH 7

Value

9.2

Moderately fast

Note

Natural light, 30-50°N

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

Value

Stable

Note

Stable at pH 4-7 up to 50 °C; pH9 DT₅₀ 120 days at 25 °C

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

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)

K_foc (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

Bio-concentration factor

BCF (l kg⁻¹)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

No data

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

methyleugenol (Ref: Ent 21040)

Known groundwater metabolites

None

Other known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 1930

Rat

Moderate

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)

> 320

Colinus virginianus

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

> 5866 mg kg bw⁻¹ day⁻¹

Colinus virginianus as product

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

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

> 1000

Low

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

0.84

Eisenia andrei corr

Moderate

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)

> 200

as product

Low

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

> 225

as product

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)

Beneficial insects (Predatory mites)

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)

> 10

Oncorhynchus mykiss

Moderate

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

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

13.0

Danio rerio

Moderate

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

1.11

Daphnia magna

Moderate

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

0.0959

Daphnia magna

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)

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)

15.4

Raphidocelis subcapitata

Low

Algae - Chronic (growth rate, fresh; 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)

Low (class I)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 1930

Rat

Moderate

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 2.58

Rat 4 hr

Other Mammal toxicity endpoints

Intraperitoneal LD₅₀ > 500 mg kg⁻¹

Mouse

Intravenous LD₅₀ = 72 mg kg⁻¹

Mouse

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

0.17

Rat SF=600

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

None allocated

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

None allocated

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

1.0

Rat SF=100

Dermal penetration studies (%)

default

Dangerous Substances Directive 76/464

Exposure Routes

Public

Acceptable for proposed uses with PPE/PPC

Occupational

Acceptable for proposed uses with PPE/PPC

Mammalian dose elimination route and rate

Extensively metabolised and rapidly excreted (<24rs) in urine

Health issues

Specific human health issues (hazard-based)

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

Harmful if ingested
Possible skin sensitiser & may cause allergic contact dermatitis
Possible liver & kidney toxicant
IARC Group 3 carcinogen - not classifiable

Handling issues

Property

Value and interpretation

General

Flammable
Not explosive or oxidising
IMDG Transport Hazard Class 9

CLP classification 2013

Health: H302, H315, H317, H319, H336

WHO Classification

Not listed (Not listed)

UN Number

UN3082

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

eugenol

French

huile essentielle de clous de girofle; eugénol

German

Danish

Italian

Spanish

Greek

Polish

2-metoksy-4-allilofenol

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	25/08/2025
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