Tetrachlorvinphos (Ref: SD 8447)

Tetrachlorvinphos (Ref: SD 8447)	Last updated: 04/09/2025
(Also known as: stirofos; CVMP)

GENERAL INFORMATION

Description

Av organophosphorus insecticide used for the control of ectoparasites

Examples of veterinary uses

Use to control ticks, flies and mites

Examples of species treated

Cats; Dogs; Cattle; Pigs; Horses

Approval status

VMR 2013/2033 approval status (GB/UK)

Not approved

EU Regulatory approval status

Not approved

Chemical structure

Isomerism

Isomeric - exists in both the Z- and E- forms. Technical products are predominately comprised of the Z-stereoisomer.

Chemical formula

C₁₀H₉Cl₄O₄P

Canonical SMILES

COP(=O)(OC)OC(=CCl)C1=CC(=C(C=C1Cl)Cl)Cl

Isomeric SMILES

COP(=O)(OC)O/C(=C\Cl)/C1=CC(=C(C=C1Cl)Cl)Cl

International Chemical Identifier key (InChIKey)

UBCKGWBNUIFUST-YHYXMXQVSA-N

International Chemical Identifier (InChI)

InChI=1S/C10H9Cl4O4P/c1-16-19(15,17-2)18-10(5-11)6-3-8(13)9(14)4-7(6)12/h3-5H,1-2H3/b10-5+

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
tetrachlorvinphos	Unstated isomer

General status

Veterinary substance type

Insecticide, Antiparasitic

Substance groups

Organophosphate insecticide; Organophosphate acaricide; Organothiophosphate insecticide; Organothiophosphate acaricide

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Acetylcholinesterase (AchE) inhibitor.

Molecular targets

[Cholinesterase, Inhibitor]

CAS RN

22248-79-9

EC number

213-506-3

CIPAC number

265

US EPA chemical code

083701 (Z) / 083702 (E)

PubChem CID

5284462

CLP index number

No data found

Therapeutic Class

Antiparasitic products, insecticides & repellents: Ectoparasiticides

ATCvet Code

QP53AF14

Controlled Drug?

Regulation 37/2010 MRL Classification

Molecular mass

365.96

PIN (Preferred Identification Name)

(1Z)-2-chloro-1-(2,4,5-trichlorophenyl)ethenyl dimethyl phosphate

IUPAC name

(Z)-2-chloro-1-(2,4,5-trichlorophenyl)vinyl dimethyl phosphate

CAS name

(1Z)-2-chloro-1-(2,4,5-trichlorophenyl)ethenyl dimethyl phosphate

Forever chemical

Other status information

Relevant Environmental Water Quality Standards

Physical state

Off-white crsytalline solid

Commercial

Property

Product

Manufacturer

Authorisation Route

Legal Class (GB/UK)

Availability status

Current

Introduction & key dates

1967, registered USA

Example products (past and present) using this active

Formulation and application details

Available in a wide variety of formulations including pet flea & tick collars, shampoos, dusts, powders and aerosol/pump sprays for direct treatment of pets and pet sleeping areas. Also used for antiparastic cattle eartags.

Commercial production

Tetrachlorvinphos is synthesised through a multi-step chemical process involving the esterification of phosphoric acid derivatives. The key reaction typically involves dimethyl phosphorochloridate reacting with a chlorinated vinylphenol compound, specifically (Z)-2-chloro-1-(2,4,5-trichlorophenyl)ethen-1-ol, to form the final product.

Impact on climate of production and use

Data for the amount of life cycle GHGs produced by tetrachlorvinphos are not available in the public domain. However, whilst estimates vary, more general data suggests that between 14 and 19 kilograms of CO₂e is emitted per kilogram of insecticide produced.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

11.6

Moderate

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

Melting point (°C)

Boiling point (°C)

Degradation point (°C)

Flashpoint (°C)

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

3.39 X 10⁰³

Calculated

Log P

3.53

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.52

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

0.0056

Low volatility

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

1.86 X 10^-04

Non-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)

Refractive Index

Environmental release

Degradation

Property

Value

Source; quality score; and other information

Interpretation

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Non-persistent

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

Note

Best available data

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)

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)

Slightly mobile

K_oc (mL g⁻¹)

900

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

0.31

Calculated

Low leachability

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

Known soil metabolites

Metabolite

Major/Minor fraction

$Click here for further information on Major/Minor fraction$

Estimated maximum occurrence fraction

Notes

desmethyltetrachlorvinphos

2,4,5-trichloroacetophenone

Aerobic

1-(2,4,5-trichloropheynl)ethanol

Aerobic

1-(2,4,5-trichlorophenyl)-2-chloroethan-1-ol

Aerobic

2-chloro-1-(2,4,5-trichlorophenyl)ethanol

Aerobic

1-(2,4,5-trichlorophenyl)ethan-1-ol

Aerobic

2,4,5-trichlorobenzoic acid

Aerobic

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

desmethyltetrachlorvinphos

Rat (Urine)

2,4,5-trichloroacetophenone

Plant

1-(2,4,5-trichlorophenyl)-2-chloroethan-1-ol

Plant

2-chloro-1-(2,4,5-trichlorophenyl)ethanol

Plant

dimethyl phosphate

Rats (Urine)

monomethyl phosphate

Rats (Urine)

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 4000

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

Rat 2 yr

(ppm diet)

125

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

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)

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

Soil micro-organisms

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

Vegetative vigour ER₅₀ (g ha⁻¹)

Seedling emergence ER₅₀ (g ha⁻¹)

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)

> 1.37

Apis mellifera

Moderate

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)

> 0.43

Oncorhynchus mykiss

Moderate

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)

0.002

Daphnia magna

High

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, fonds growth, fresh) - 7 day (mg l⁻¹)

Aquatic plants (rooted, growth rate, fresh) - 14 day (mg l⁻¹)

Algae - Acute (growth rate, fresh; mg l⁻¹)

Algae - Chronic (growth rate, fresh; 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)

> 4000

Rat

Low

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

1500

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.85

Rat

Other Mammal toxicity endpoints

Intraperitoneal LD₅₀ > 5000 mg kg⁻¹

Guinea pig

Subcutaneous LD₅₀ > 5000 mg kg⁻¹

Rabbit

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

List I; List II

Exposure Routes

Public

Occupational

May be absorbed through the skin

Mammalian dose elimination route and rate

Metabolised and mainly excreted in the urine

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

IARC Group 2B carcinogen; US EPA - likely to be human carcinogen
Kidney and liver toxicant
Suspected of causing genetic defects
Repeated or prolonged skin contact may cause allergic reactions with susceptible person

Handling issues

Property

Value and interpretation

General

IMDG Transport Hazard Class 6.1
Highly flammable

CLP classification 2013

Health: H302, H312, H332, H341
Environment: H400, H410

WHO Classification

III (Slightly hazardous)

UN Number

UN3018

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

tetrachlorvinphos

French

tétrachlorvinphos

German

Tetrachlorvinphos

Danish

tetrachlorvinphos

Italian

tetraclorvinfos

Spanish

tetraclorvinfos

Greek

Polish

tetrachlorwinfos

Swedish

Hungarian

Dutch

tetrachloorvinvos

Norwegian

Record last updated:	04/09/2025
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