Fatty acids (generic C7-C18)

Fatty acids (generic C7-C18)	Last updated: 26/05/2025
(Also known as: nonaoic; soap)

SUMMARY

A naturally occurring soap insecticide and acaricide used to control soft-bodied pests but which also has other applications in crop protection. It has a low water solubility and is quite volatile. It is not persistent in water systems. There are no major concerns regarding its impact on human health having a low oral toxicity but may irritate skin and eyes. Risks to biodiversity are also considered low to moderate..

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: Drainflow: Moderately mobile; Potential for particle bound transport: Medium	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Bees acute oral ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate	Human health Low alert

GENERAL INFORMATION

Description

A soap concentrate insecticide and acaricide used to control soft-bodied pests. Also used as an additive in formulations and as an adjuvant

Example pests controlled

Aphids; Mealybugs; Thrips

Example applications

Vegetables; Fruit; Ornamentals

Efficacy & activity

Availability status

Current

Introduction & key dates

1947, first registration of soaps as pesticides in US; 2021, EU approval expired

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/08/2029

GB LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved (as potassium salts)

Dossier rapporteur/co-rapporteur

Greece/Austria

Date EC 1107/2009 inclusion expires

01/12/2026

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

USA

Chemical structure

Isomerism

Chemical formula

C₇H₁₄O₂ to C₁₈H₃₄O₂

Canonical SMILES

Isomeric SMILES

International Chemical Identifier key (InChIKey)

International Chemical Identifier (InChI)

2D structure diagram/image available?

Yes

General status

Pesticide type

Insecticide; Fungicide; Semiochemical; Other substance

Other bioactivity & uses

Surfactant; Adjuvant

Substance groups

Plant-derived substance; Animal-derived substance

Minimum active substance purity

Known relevant impurities

Substance origin

Natural; Complex mixture

Mode of action

Contact action. Fatty acids disrupt the cell membranes of insects causing them to dehydrate and die

CAS RN

EC number

CIPAC number

None allocated

US EPA chemical code

PubChem CID

CLP index number

889

Molecular mass

Variable

PIN (Preferred Identification Name)

IUPAC name

Fatty acids (C7 to C18)

CAS name

Nonanoic acids

Other status information

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)

UNE

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Physical state

Colourless solid to liquid material depending on chemical composition. Composition is a complex mic of palmitic acid (~45%), oleic acid (~20%) plus arachidic acid, stearic acid, linoleic acid and other substances.

Related substances & organisms

pelargonic acid

isobutyric acid

isovaleric acid

valeric acid

fatty acids unsaturated potassium salts (generic C7-C18)

capric acid

Formulations

Property

Value

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

Example products using this active

Formulation and application details

Often supplied as a soluble concentrate which is mixed with water and applied as a foliar spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.012

at 25 °C

Low

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

250000

n-Heptane

250000

p-Xylene

250000

1,2-Dichloroethane

250000

Acetone

Melting point (°C)

Boiling point (°C)

Degradation point (°C)

350

Flashpoint (°C)

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

4.37 X 10⁰⁷

Calculated

Log P

7.64

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

4.9

Vapour pressure at 20 °C (mPa)

900

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)

0.33

Moderately 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)

34.6

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Non-persistent

DT₅₀ (lab at 20 °C)

Non-persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

Non-persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU Dossier

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)

Moderately mobile

K_oc (mL g⁻¹)

137

Notes and range

estimated

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

0.89

Calculated

Low leachability

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

Value

2.06 X 10^-03

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

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

Bio-concentration factor

BCF (l kg⁻¹)

255

Threshold for concern

CT₅₀ (days)

Not available

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

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)

> 2510

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

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

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

> 105

Eisenia foetida 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

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)

> 96.04

Apis mellifera

Moderate

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

21280

Aphidius rhopalosiphi

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

5900

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)

8.8

Salmo gairdneri

Moderate

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

5.0

Oncorhynchus mykiss

Moderate

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

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

> 1.2

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, growth) - Acute 7 day EC₅₀, biomass (mg l⁻¹)

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

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

1.2

Scenedesmus subspicatus

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)

Not applicable

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 1.82

Rat 4 hr (nose only)

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

Occupational

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

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

Not explosive or oxidising
Corrosive
Not explected to auto-ignite, Not highly flammable

CLP classification 2013

Health: H315, H319, H335
Environment: H411

WHO Classification

Not listed (Not listed)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

fatty acids (generic C7-C18)

French

acides gras

German

Fettsäuren

Danish

fedtsyrer

Italian

acidi grassi

Spanish

acido graso

Greek

Polish

kwasy tluszczowe

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	26/05/2025
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