Eugenol

Eugenol	Last updated: 31/10/2024
(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.

Availability status

Current

Introduction & key dates

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)-

Other status information

Highly phytotoxic

Relevant Environmental Water Quality Standards

Physical state

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

Related substances & organisms

clove oil

Formulations

Property

Product

Manufacturer

Authorisation Route

Legal Class (GB/UK)

Example products (past and present) using this active

Formulation and application details

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)

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)

> 1000

Low

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

0.84

Eisenia andrei corr

Moderate

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)

> 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

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 - Acute 7 day EC₅₀, biomass (mg l⁻¹)

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

15.4

Pseudokirchneriella subcapitata

Low

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

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves – Acute EC₅₀ development (mg l⁻¹)

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

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:	31/10/2024
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