Indolylbutyric acid

Indolylbutyric acid	Last updated: 23/02/2024
(Also known as: beta-indolebutyric acid ; IBA)

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: Slightly mobile Warning: Significant data are missing	Ecotoxicity Low alert: Birds acute ecotoxicity: Low; Fish acute ecotoxicity: Low; Daphnia acute ecotoxicity: Low	Human health High alert: Reproduction/development effects

GENERAL INFORMATION

Description

A botanical auxin extract used to improve rootings of woody plant cuttings in horticulture

Example pests controlled

Improved propagation

Example applications

Ornamentals

Efficacy & activity

Evaluated via trials

Appearance and life cycle

Availability status

Current

Introduction & key dates

Taxonomic classification

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/05/2026

UK LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Greece

Date EC 1107/2009 inclusion expires

31/05/2023

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

Known to be used in the following countries

Chemical structure

Isomerism

Chemical formula

C₁₂H₁₃NO₂

Canonical SMILES

C1=CC=C2C(=C1)C(=CN2)CCCC(=O)O

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

JTEDVYBZBROSJT-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C12H13NO2/c14-12(15)7-3-4-9-8-13-11-6-2-1-5-10(9)11/h1-2,5-6,8,13H,3-4,7H2,(H,14,15)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
indolylbutyric acid	-

General status

Biopesticide type

Plant Growth Regulator, Herbicide

Substance groups

Plant derived substance

Minimum active substance purity

994 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Natural

Mode of action

Broad spectrum, effects cell division and elongation stimulating the formation of roots.

Substance source

A plant hormone of the auxin family - some reports say its synthetic others report its isolation from leaves and seeds of maize, and from the salix (willow) genus

Substance production

Synthesised for commercial use

Uses

Yield enhancement

Target pests

None - PGR

Target host

Plant cuttings for rooting

Farming system suitability

CAS RN

133-32-4

EC number

205-101-5

CIPAC number

830

US EPA chemical code

046701

PubChem CID

Molecular mass

203.24

PIN (Preferred Identification Name)

IUPAC name

4-indol-3-ylbutyric acid

CAS name

1H-indole-3-butanoic acid

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Not applcable

Herbicide Resistance Class (WSSA MoA class)

Insecticide Resistance Class (IRAC MoA class)

Not applcable

Fungicide Resistance Class (FRAC MOA class)

Not applcable

Examples of recorded resistance

Physical state

Beige to white coloured crystalline powder

Formulations

Property

Product

Manufacturer

Example products

Indole-3-butyric acid

Mallinckrodt Baker

Indole-3-butyric acid Rooting Powder

Research Products International

Hormex Rooting Powder #8

Brooker Chemical Corps

Formulation and application details

Usually supplied as a dusting powder.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

14700

High

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

160000

Ethyl acetate

250000

Acetone

250000

Methanol

20000

Dichloromethane

Melting point (°C)

124

Boiling point (°C)

250

Degradation point (°C)

157

Flashpoint (°C)

211.8

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

2.29 X 10⁰⁰

Calculated

Log P

0.36

Low

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.25

Dissociation constant pKa) at 25 °C

4.7

Weak acid

Vapour pressure at 20 °C (mPa)

0.01

Low volatility

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

2.32 X 10^-07

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Neutral solution: 291nm=5980, 282nm=6900, 277nm=6390, 224nm=36500
Acidic solution: 291nm=4640, 282nm=5450, 276nm=5040, 223nm=27100
Basic solution: 291nm=5480, 283nm=6390, 277nm=5890

Surface tension (mN m⁻¹)

69.1

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)

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.

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

Slightly mobile

K_oc

550

Notes and range

Estimated

Freundlich

K_f

K_foc

¹/_n

Notes and range

pH sensitivity

Known soil and groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

indolylacetic acid

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)

2150

Colinus virginianus

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)

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)

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

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)

240

Oncorhynchus mykiss

Low

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)

112

Daphnia magna

Low

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 - Acute 7 day EC₅₀, biomass (mg l⁻¹)

Lemna gibba Biomass

Low

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

> 180

Pseudokirchneriella subcapitata

Low

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

Pseudokirchneriella subcapitata

Low

Mesocosm study data

NOEAEC mg l⁻¹

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 - Dermal LD₅₀ (mg kg⁻¹ body weight)

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 5.0

Rat 4hr

Other Mammal toxicity endpoints

Intraperitoneal LD₅₀ = 1410 mg kg⁻¹ BW

Rat

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)

0.025

Rabbit SF=1000

Dermal penetration studies (%)

5.8

Dangerous Substances Directive 76/464

Exposure Routes

Public

The public may be exposed via dermal contact with consumer products containing indolylbutyric acid

Occupational

PPE/PPC recommended

Mammalian dose elimination route and rate

Rapidly excreted within 24hrs via urine (80-84%) and faeces (16-19%)

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

General human health issues

Possible liver & kidney toxicant
May be harmful if swallowed

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 6.1
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H302, H319, H361d, H361f

WHO Classification

III (Slightly hazardous)

UN Number

UN2811

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

Limited shelf-life. Store at 2-8 DegC

TRANSLATIONS

Language

Name

English

indolylbutyric acid

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Polish

Swedish

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Record last updated:	23/02/2024
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