Kaolin	Last updated: 26/10/2023
(Also known as: argilla; bentone; china clay; porcelain clay; neokaolin ; aluminium silicate hydrate; hydrated aluminium silicate)

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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
	Ecotoxicity Low alert: Birds acute ecotoxicity: Low; Fish acute ecotoxicity: Low; Daphnia acute ecotoxicity: Low; Bees acute contact ecotoxicity: Low; Bees acute oral ecotoxicity: Low; Earthworms acute ecotoxicity: Low	Human health High alert: Carcinogen; Reproduction/development effects

GENERAL INFORMATION

Description	Used as a feed supplement for livestock to prevent diarrheal diseases
Availability status	Current
Introduction & key dates	1997, first registered as pesticide USA
Examples of species treated	Pigs, Dogs, Cats, Poultry

Chemical structure

Isomerism	None
Chemical formula	H₄Al₂O₉Si₂
Canonical SMILES	O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O
Isomeric SMILES	-
International Chemical Identifier key (InChIKey)	NLYAJNPCOHFWQQ-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/2Al.O5Si2.2H2O.2O/c;;1-6(2)5-7(3)4;;;;/h;;;2*1H2;;/q2*+1;-2;;;;
2D structure diagram/image available?	Yes

General status

Veterinary substance type	Feed additive
Other constituent type	Coating agent
Substance groups	Inorganic compound
Minimum active substance purity	-
Known relevant impurities	-
Substance origin	Natural
Mode of action	Mainly non-toxic mode of action, acts via its physical properties but may also interfere with feeding behaviour and egg-laying
Molecular targets	-
CAS RN	1332-58-7
EC number	310-194-1
CIPAC number	None allocated
US EPA chemical code	100104
PubChem CID	56841936
CLP index number	No data found
ATCvet Code	QA07AA51
Therapeutic Class	Alimentary tract & metabolism: Intestinal antiinfectives
Controlled Drug?	No
Regulation 37/2010 MRL Classification	No data
Molecular mass	258.16
PIN (Preferred Identification Name)	-
IUPAC name	oxo-oxoalumanyloxy-[oxo(oxoalumanyloxy)silyl]oxysilane;dihydrate
CAS name	aluminium silicate hydrate
Other status information	-
Relevant Environmental Water Quality Standards	-
Physical state	Off-white coloured powder

Formulations

Property	Product	Manufacturer	Authorisation Route	UK Legal Class
Example products using this active	Kaogel VP 19.72% w/v Oral Suspension	Pfizer Ltd	UK National authorisation	Authorised veterinary medicine for general sale (AVM - GSL)
	Kaolin Poultice B.P	KL Pharmaceutical Ltd	UK National authorisation	Authorised veterinary medicine for general sale (AVM - GSL)
Formulation and application details	-

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		5.0	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	Low
Solubility - In organic solvents at 20 °C (mg l⁻¹)		-	-	-
Melting point (°C)		1760	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Boiling point (°C)		-	-	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	Not applicable	-	-
	Log P	Not applicable	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	Not applicable
Fat solubility of residues	Solubility	-	-	-
	Data type	-	-	-
Density (g ml⁻¹)		2.6	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Dissociation constant pKa) at 25 °C		-	-	-
		-
Vapour pressure at 20 °C (mPa)		-	-	-
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		-	-	-
Maximum UV-vis absorption L mol⁻¹ cm⁻¹		-	-	-
Surface tension (mN m⁻¹)		-	-	-
Refractive Index		1.620	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-

Degradation

Property		Value	Source; quality score; and other information	Interpretation
Soil degradation (days) (aerobic)	DT₅₀ (typical)	1000	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	Very persistent
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	Note	Kaolin is a non-degradable natural component of the environment
Manure DT₅₀ (days)		-	-	-
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)		-	-	-

Soil adsorption and mobility

Property		Value	Source; quality score; and other information	Interpretation
Linear	Kd	-	-	-
	Koc	-
	Notes and range	Kaolin is a natural component of the environment
Freundlich	Kf	-	-	-
	Kfoc	-
	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)	20	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source Low risk	Low potential
	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	R4 R = Peer reviewed scientific publications 4 = Verified data 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)		> 5000	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Unknown species	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)		> 2000	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Eisenia foetida	Low
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	R4 R = Peer reviewed scientific publications 4 = Verified data Apis mellifera	Low
	Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	> 100	R4 R = Peer reviewed scientific publications 4 = Verified data Apis mellifera	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
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		> 2500	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Unknown species	Low
Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		> 2500	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Unknown species	Low
Aquatic invertebrates - Chronic 21 day NOEC (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)		> 2500	A4 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 4 = Verified data Unknown species	Low
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		-	-	-
Mesocosm study data	NOEAEC mg l⁻¹	-	-	-
	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	R4 R = Peer reviewed scientific publications 4 = Verified data Rat	Low
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		5000	R4 R = Peer reviewed scientific publications 4 = Verified data Rat	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		-	-	-
Other Mammal toxicity endpoints		-	-	-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)		None allocated	A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes	-
ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)		None allocated	A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes	-
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	A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes	-
Dermal penetration studies (%)		-	-	-
Dangerous Substances Directive 76/464		-	-	-
Exposure Routes	Public	-
	Occupational	-
Mammalian dose elimination route and rate		Poorly absorbed from the gastrointestinal tract, has a short half-life and is nearly all excreted unchanged	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor ✓Yes, known to cause a problem A0 A = Chromosome aberration (EFSA database) 0 = No data ; B0 B = DNA damage/repair (EFSA database) 0 = No data ; C0 C = Gene mutation (EFSA database) 0 = No data ; D0 D = Genome mutation (EFSA database) 0 = No data ; E3 E = Unspecified genotoxicity type (miscellaneous data source) 3 = Negative XNo, known not to cause a problem Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant ✓Yes, known to cause a problem XNo, known not to cause a problem XNo, known not to cause a problem Respiratory tract irritant Skin irritant Skin sensitiser ?Possibly, status not identified ✓Yes, known to cause a problem ?Possibly, status not identified Eye irritant Phototoxicant   ✓Yes, known to cause a problem No data found
General human health issues		Inhalation may cause pneumoconiosis (Kaolinosis) May produce gastrointestinal disturbances as high doses Possible respiratory sensitiser May cause toxic responses via inhalation CLP data - known human carcinogen

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	Health: H315, H319, H334, H335, H350, H370, H372, H373
WHO Classification	Not listed (Not listed)
UN Number	-
Waste disposal & packaging	-
Shelf-life, storage, stability and reactivity	-

TRANSLATIONS

Language	Name
English	kaolin
French	kaolin
German	Porzellanerde
Danish	kaolin
Italian	caolino
Spanish	caolin
Greek	kaoline
Polish	-
Swedish	kaolin
Hungarian	porcelanfold
Dutch	kaolien
Norwegian	-

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Record last updated:	26/10/2023
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