Aluminium silicate

Aluminium silicate	Last updated: 04/01/2025
(Also known as: kaolin; china clay; bolus alba; hydrated aluminium silicate; porcelain clay; pyrophylite; bentone; argilla)

SUMMARY

Aluminium silicate is an insecticide and insect repellent. It has a low mammalian toxicity. Aluminium silicate is virtually insoluble in water and in many organic solvents. Little data has been published regarding its environmental fate. It is moderately toxic to fish and honeybees.

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 Low alert: Potential for particle bound transport: Low Warning: Significant data are missing	Ecotoxicity Low alert: Fish acute ecotoxicity: Low; Fish chronic ecotoxicity: Low; Bees acute contact ecotoxicity: Low; Bees acute oral ecotoxicity: Low Warning: Significant data are missing	Human health Moderate alert: Reproduction/development effects Warning: Significant data are missing

GENERAL INFORMATION

Description

An inorganic salt without pesticidal activity that is used as an insect repellent on top fruit and vines.

Example pests controlled

Aphids; Plant lice; Leaf roller; Pear psylla; Flea beetles; Japanese beetles; Weevils; Sawflies; Thrips

Example applications

Fruit including apples, pears, plums, grapes, cherries, berries; Row field crops

Efficacy & activity

Availability status

Current

Introduction & key dates

1997, first registered as pesticide USA

GB regulatory status

GB COPR regulatory status

Not approved

Date COPR inclusion expires

Not applicable

GB LERAP status

Not applicable

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Greece/France

Date EC 1107/2009 inclusion expires

31/03/2026

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

Chemical structure

Isomerism

None

Chemical formula

Al₂O₅Si

Canonical SMILES

[O-2].[O-2].[O-2].[O-2].[O-2].[Al+3].[Al+3].[Si+4]

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

XLIDPNGFCHXNGX-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/2Al.5O.Si/q2*+3;5*-2;+4

2D structure diagram/image available?

Yes

General status

Pesticide type

Insecticide; Semiochemical; Other substance

Other bioactivity & uses

Diluent

Substance groups

Inorganic compound

Minimum active substance purity

999.8 g kg⁻¹

Known relevant impurities

Substance origin

Natural

Mode of action

Biochemically inert - used in pesticide product formulations to form a barrier film preventing target pests from reaching plant.

CAS RN

1302-87-0

EC number

934-756-6

CIPAC number

841

US EPA chemical code

00104

PubChem CID

8488719

CLP index number

No data found

Molecular mass

162.05

PIN (Preferred Identification Name)

dialuminum;oxygen(2-);silicon(4+)

IUPAC name

dialuminum;oxygen(2-);silicon(4+)

CAS name

aluminium silicate anhydrous

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)

UNM

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Physical state

Soft grey-white powder

Related substances & organisms

kaolin calcined

kaolin

Formulations

Property

Value

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

Example products using this active

Surround WP Crop Protectant
Strafer

Formulation and application details

Usually formulated as a wettable power, mixed with water and applied as a broadcast spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

Insoluble

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

Insoluble

Acetone

Insoluble

Ethyl acetate

Insoluble

n-Heptane

Insoluble

Xylene

Melting point (°C)

Boiling point (°C)

Degradation point (°C)

Does not sublime or decompose

Flashpoint (°C)

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

Log P

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

Non-volatile

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

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Not measureable

Surface tension (mN m⁻¹)

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

0.1

Non-persistent

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

0.1

Non-persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Natural substance that rapidly disperses in the environment

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

Stable

Note

Stable at all pH's

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

Value

Stable

Note

Stable at all pH's

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

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

Value

Cannot be calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Calculated

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

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

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)

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)

> 100

Low

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

> 1000

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)

> 100

Oncorhynchus mykiss

Low

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

. 500

Unknown species

Low

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

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

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)

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)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 5000

Rat

Low

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

5000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 2.18

Rat 4 hr

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)

None allocated

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

No data found

; ; ; ;

No data found

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

May cause gastrointestinal effects
Antidiarrhoeal agent

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H315, H318, H319, H335

WHO Classification

Not listed (Not listed)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

aluminium silicate

French

acide silicique sel d'aluminium

German

Kieselsaure, aluminiumsalz

Danish

Italian

Spanish

acido silicico sal de aluminio

Greek

Polish

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	04/01/2025
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