Sumithrin

Sumithrin	Last updated: 12/09/2025
(Also known as: d-phenothrin; phenothrin; (+)-cis-Phenothrin)

GENERAL INFORMATION

Description

A synthetic pyrethroid used as an animal insecticde

Examples of veterinary uses

Used to eradicate adult fleas and ticks

Examples of species treated

Dogs; Cats

Approval status

VMR 2013/2033 approval status (GB/UK)

Not approved

EU Regulatory approval status

Not approved

Chemical structure

Isomerism

Sumithrin is isomeric and is comprised largely (>=95%) of a 1:4 mixture of the 1R-cis and 1R-trans phenothrin isomers

Chemical formula

C₂₃H₂₆O₃

Canonical SMILES

CC(=CC1C(C1(C)C)C(=O)OCC2=CC(=CC=C2)OC3=CC=CC=C3)C

Isomeric SMILES

CC(=C[C@H]1[C@H](C1(C)C)C(=O)OCC2=CC(=CC=C2)OC3=CC=CC=C3)C

International Chemical Identifier key (InChIKey)

SBNFWQZLDJGRLK-SFTDATJTSA-N

International Chemical Identifier (InChI)

InChI=1S/C23H26O3/c1-16(2)13-20-21(23(20,3)4)22(24)25-15-17-9-8-12-19(14-17)26-18-10-6-5-7-11-18/h5-14,20-21H,15H2,1-4H3/t20-,21-/m0/s1

2D structure diagram/image available?

Yes

General status

Veterinary substance type

Ectoparasiticide

Substance groups

Pyrethroid insecticide; Pyrethroid ester insecticide

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Non-systemic with rapid contact and stomach action. Sodium channel modulator.

Molecular targets

[Sodium channel, Modulator]

CAS RN

51186-88-0

Alternative/old CAS RN

74430-92-5

EC number

257-040-9

CIPAC number

356

US EPA chemical code

PubChem CID

187827

CLP index number

No data found

Therapeutic Class

ATCvet Code

None allocated

Controlled Drug?

Regulation 37/2010 MRL Classification

Molecular mass

350.46

PIN (Preferred Identification Name)

(3-phenoxyphenyl)methyl (1R,3S)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

IUPAC name

(3-phenoxyphenyl)methyl (1R,3S)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

CAS name

(3-phenoxyphenyl)methyl 2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate

Forever chemical

Other status information

Marine Pollutant

Relevant Environmental Water Quality Standards

Physical state

Yellow-brown liquid

Related substances & organisms

d-phenothrin

Commercial

Property

Value

Availability status

Current

Introduction & key dates

1976, registered Japan

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

Sumitomo

Example products using this active

Sumithrin SEC

Formulation and application details

Primarily formulated for topical or aerosol applications typically as sprays, foggers and pet shampoos

Commercial production

Sumithrin is synthesised through a multi-step organic process typical of synthetic pyrethroids. The production begins with the preparation of the acid moiety, specifically a cyclopropane carboxylic acid derivative, which is formed via cyclopropanation reactions involving alkenes and diazo compounds. Separately, the alcohol moiety, typically 3-phenoxybenzyl alcohol, is synthesized through etherification of phenol derivatives. These two components are then joined in an esterification reaction, producing the final ester compound.

Impact on climate of production and use

Data for the amount of life cycle GHGs produced by sumithrin 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)

0.0097

Low

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

Melting point (°C)

Boiling point (°C)

290

Degradation point (°C)

Flashpoint (°C)

107

(closed cup)

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

1.02 X 10⁰⁶

Calculated

Log P

6.01

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.06

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

0.021

at 25°C

Low volatility

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

6.75 X 10^-01

Moderately 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)

Moderately persistent

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

Note

Best available literature data gives soil half life between 14 and 60 days

Manure DT₅₀ (days)

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Note

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

Value

Stable

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)

Non-mobile

K_oc (mL g⁻¹)

180000

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

-1.94

Calculated

Low leachability

Bio-concentration factor

BCF (l kg⁻¹)

730

Cyprinidae

Threshold for concern

CT₅₀ (days)

Not available

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)

> 2500

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

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)

0.07

Apis mellifera

High

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

0.16

Apis mellifera

High

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)

> 0.016

Oncorhynchus mykiss

High

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)

> 0.0043

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)

> 0.00002

Americamysis bahia

High

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)

> 5000

Rat

Low

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 2.1

Rat

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

About 60% of dose is eliminated in urine and 40% in faeces in 3 days

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

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

May cause dizziness, headaches, fatigue and diarrhoea
Endocrine issues - Increase of estrogen-sensitive cells proliferation
Possible liver and kidney toxicant

Handling issues

Property

Value and interpretation

General

Prevent generation of mists

CLP classification 2013

Environment: H400, H410

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

sumithrin

French

phenothrine

German

Phenothrin

Danish

phenothrin

Italian

fenotrin

Spanish

fenotrin

Greek

Polish

fenotryna

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	12/09/2025
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