Triclabendazole (Ref: CGA 89317)	Last updated: 26/04/2021
(Also known as: CGA 89317)

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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 Moderate alert: Fish acute ecotoxicity: Moderate Warning: Significant data are missing	Human health Low alert

GENERAL INFORMATION

Description	Oral anthelmintic for the control of liver flukes in cattle, sheep and goats
Availability status	-
Introduction & key dates	-
Examples of species treated	Cattle, Sheep, Goats

Chemical structure

Isomerism	-
Chemical formula	C₁₄H₉Cl₃N₂OS
Canonical SMILES	CSC1=NC2=CC(=C(C=C2N1)Cl)OC3=C(C(=CC=C3)Cl)Cl
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	NQPDXQQQCQDHHW-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C14H9Cl3N2OS/c1-21-14-18-9-5-8(16)12(6-10(9)19-14)20-11-4-2-3-7(15)13(11)17/h2-6H,1H3,(H,18,19)
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
triclabendazole	-

General status

Veterinary substance type	Anthelmintic, Antiparasitic Medicinal drug
Substance groups	Benzimidazole
Minimum active substance purity	>97%
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	It binds to tubulin impairing intracellular transport mechanisms and interferes with protein synthesis.
Molecular targets	-
CAS RN	68786-66-3
EC number	-
CIPAC number	-
US EPA chemical code	-
PubChem CID	-
ATCvet Code	QP52AC01
Therapeutic Class	Antiparasitic products, insecticides & repellents: Anthelmintics
Controlled Drug?	No
Regulation 37/2010 MRL Classification	Allowed substance (Table 1: Ruminants)
Molecular mass	359.66
PIN (Preferred Identification Name)	-
IUPAC name	5-chloro-6-(2,3-dichlorophenoxy)-2-(methylthio)-1H-benzimidazole
CAS name	6-chloro-5-(2,3-dichlorophenoxy)-2-methylthio-benzimidazole
Other status information	-
Relevant Environmental Water Quality Standards	-
Physical state	White to brown crystalline powder

Formulations

Property	Product	Manufacturer	Authorisation Route	UK Legal Class
Example products using this active	Combinex Cattle Oral Suspension	Novartis Animal Health	UK National authorisation	Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
	Endofluke 100 mg/ml Oral Suspension	Cross VetPharm Group	EU Mutually recognised procedure	Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
	Tribex 10% Oral Suspension for Cattle	Chanelle Animal Health	EU Mutually recognised procedure	Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
	Triclafas Drench 5% w/v Oral Suspension	Norbrook Labs	UK National authorisation	Prescription only medicine to be authorised by suitably qualified person (POM-VPS)
Formulation and application details	Usually formulated for oral administration

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		1.0	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)		175	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Boiling point (°C)		496	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		253.7	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source	-
Octanol-water partition coefficient at pH 7, 20 °C	P	-	-	-
	Log P	-	-	-
Fat solubility of residues	Solubility	-	-	-
	Data type	-	-	-
Density (g ml⁻¹)		1.59	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		1.724	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)	-	-	-
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	Note	-
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	-
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)	-	-	-
	CT₅₀ (days)	-		-

Known soil and groundwater metabolites

None

Other known metabolites

Metabolite name and reference	Aliases	Formation medium / Rate	Estimated maximum occurrence fraction	Metabolising enzymes
2-benzimidazolone	-	Animal (Urine and Faeces)	-	-
triclabendazole sulfoxide	-	Animal (Faeces)	-	-
triclabendazole sulfone	-	Animal (Faeces)	-	-
4-hydroxy triclabendazole	-	Animal (Faeces)	-	-

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property		Value	Source; quality score; and other information	Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		> 5000	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 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)		-	-	-
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
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		0.14	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source Oncorhynchus mykiss	Moderate
Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		-	-	-
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)		-	-	-
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	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Rat	Low
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		4000	Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source Rat	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		> 0.5	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source Rat 4 hr	-
Other Mammal toxicity endpoints		-	-	-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)		-	-	-
ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)		-	-	-
AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)		-	-	-
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)		-	-	-
Dermal penetration studies (%)		-	-	-
Dangerous Substances Directive 76/464		-	-	-
Exposure Routes	Public	-
	Occupational	-
Mammalian dose elimination route and rate		Mostly metabolised and excreted via urine and faeces. Also identified unchanged in breast milk.	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor XNo, known not 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 No data found XNo, known not to cause a problem XNo, known not to cause a problem Respiratory tract irritant Skin irritant Skin sensitiser ✓Yes, known to cause a problem ✓Yes, known to cause a problem No data found Eye irritant Phototoxicant   ✓Yes, known to cause a problem No data found
General human health issues		Possible liver and kidney toxicant

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	-
WHO Classification	Not listed (Not listed)
UN Number	-
Waste disposal & packaging	-
Shelf-life, storage, stability and reactivity	-

TRANSLATIONS

Language	Name
English	triclabendazole
French	-
German	-
Danish	-
Italian	-
Spanish	triclabendazol
Greek	-
Polish	-
Swedish	-
Hungarian	-
Dutch	-
Norwegian	-

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Record last updated:	26/04/2021
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