D-limonene

D-limonene	Last updated: 26/08/2025
(Also known as: dipentene; d-limonene; alpha-limonene; dipenol; orange oil; citrus extract)

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
	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate	Human health Moderate alert: Reproduction/development effects

GENERAL INFORMATION

Description

An insect repellant with a strong citrus smell used alone or in combination with other insecticides mainly used for public health

Example pests controlled

Fleas; Ticks; Mosquito larvae

Example applications

Animals; Humans

Efficacy & activity

Appearance and life cycle

Taxonomic classification

GB regulatory status

GB COPR regulatory status

Not approved in this pure form but approved as part of some plant oils

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 in this pure form but approved as part of some plant oils

Dossier rapporteur/co-rapporteur

Not applicable

Date EC 1107/2009 inclusion expires

Not applicable

EU Candidate for substitution (CfS)

Not applicable

Listed in EU database

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

Known to be also used in the following countries

USA

Chemical structure

Isomerism

d-limonene is one of two optical isomers of limonene, due to a chiral centre at the carbon adjacent to the double bond in its ring structure. This chirality gives rise to enantiomeric isomerism forming d-limonene (R-limonene) and l-limonene (S-limonene). These enantiomers vary in biological activity, with d-limonene more commonly used in pest control

Chemical formula

C₁₀H₁₆

Canonical SMILES

CC1=CCC(CC1)C(=C)C

Isomeric SMILES

CC1=CC[C@@H](CC1)C(=C)C

International Chemical Identifier key (InChIKey)

XMGQYMWWDOXHJM-JTQLQIEISA-N

International Chemical Identifier (InChI)

InChI=1S/C10H16/c1-8(2)10-6-4-9(3)5-7-10/h4,10H,1,5-7H2,2-3H3

2D structure diagram/image available?

Yes

General status

Biopesticide type

Insecticide; Semiochemical; Veterinary substance; Metabolite; Other substance

Metabolite Type

Groundwater; Soil; Surface water

Other bioactivity & uses

Biocide; Slimicide

Substance groups

Plant-derived substance

Minimum active substance purity

Known relevant impurities

Substance origin

Natural

Mode of action

Odourous repellent

Substance source

A compound found in high quantities in citrus fruits especially oranges

Uses

Public health applications

Target pests

Fleas; Ticks; Mosquito larvae

Target host

Animals; Humans

Farming system suitability

Not normally used in agriculture production

CAS RN

5989-27-5

EC number

227-813-5

CIPAC number

None allocated

US EPA chemical code

PubChem CID

Molecular mass

136.23

PIN (Preferred Identification Name)

IUPAC name

(R)-4-isopropenyl-1-methylcyclohexene

CAS name

(4R)-1-methyl-4-(1-methylethenyl)cyclohexene

Forever chemical

Other status information

FEMA=2633; FLAVIS=01.045

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)

UNM

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Physical state

Colourless to pale yellow liquid with citrus odour

Related substances & organisms

orange oil

Can be a metabolite of:

Parent

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

orange oil

Soil

Commercial

Property

Value

Availability status

Current

Introduction & key dates

1958, registered USA

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

Bma Inc, USA
Orange Guard Inc
BASF Speciality Chemicals

Example products using this active

Natural Mosquito and Bug Repellant
Orange Guard
MotherEarth ProCitra-DL

Formulation and application details

Usually suppled as ready-to-use formulations such as sprays and as emulsifiable concentrates, granules and impregnated collars

Commercial production

d-Limonene is primarily produced commercially through the extraction from citrus fruit peels, especially oranges. The peels of citrus fruits are subjected to a process called cold pressing or steam distillation to extract the essential oils, which contain d-limonene. The essential oil is then separated from the water and other components, typically using centrifugation or decantation. The crude d-limonene is further purified to remove any impurities. This can involve additional distillation or filtration steps to achieve the desired purity level. Alternatively, a process using supercritical carbon dioxide can be used to extract the essential oil from citrus peel. There is also growing interest in microbial production of d-limonene which involves using genetically engineered microorganisms, such as Escherichia coli or Saccharomyces cerevisiae, to produce d-limonene through fermentation processes.

Impact on climate of production and use

According to a published LCA the production of d-limonene from citrus waste emits approximately 0.3 to 0.5 tonnes of CO₂e per tonne of d-limonene produced. This is significantly lower than petroleum-derived solvents like acetone or toluene, which can emit 2–5 tonnes CO₂e per tonne.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

13.8

at 25 °C

Moderate

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

Melting point (°C)

-73.5

Boiling point (°C)

175

Degradation point (°C)

Flashpoint (°C)

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

1.70 X 10⁰⁴

Calculated

Log P

4.23

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

160000

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)

1580

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)

28.5

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Note

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

Value

Note

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

Known metabolites

None

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 dietary NOEL

(mg kg⁻¹)

(ppm diet)

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

Birds - Acute LD₅₀ (mg kg⁻¹)

Birds - Short term dietary (LC₅₀/LD₅₀)

> 1405 mg kg bw⁻¹ day⁻¹

Colinus virginianus

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

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

999.7

as product corr

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)

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

> 100

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) as Mortality LR₅₀ g ha⁻¹, Std lab test

~ 96

Aphidius rhopalosiphi

Moderate

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

~ 175

Typhlodromus pyri

Low

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)

0.702

Pimephales promelas

Moderate

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

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

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

0.421

Daphnia magna

Moderate

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

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)

4.08

Desmodesmus subspicatus

Moderate

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)

> 5000

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

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

None allocated

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)

None allocated

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

Acceptable for proposed uses

Occupational

Acceptable for proposed uses

Mammalian dose elimination route and rate

Rapidly excreted (2-3 days) majority in urine & less than 10% in faeces

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

No further information available

Handling issues

Property

Value and interpretation

General

Flammable
Not explosive or oxidising

CLP classification 2013

Health: H317

WHO Classification

Not listed (Not listed)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

d-limonene

French

D-limonene

German

D-Limonen

Danish

D-limonen

Italian

D-limonene

Spanish

D-limonene

Greek

Polish

D-limonen

Swedish

Hungarian

Dutch

dipenteen

Norwegian

Record last updated:	26/08/2025
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