Tefluthrin (Ref: R 151993)

Tefluthrin (Ref: R 151993)	Last updated: 22/10/2025
(Also known as: tefluthrine)

SUMMARY

Hazard 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. These hazard alerts do not take account of usage patterns or exposure, thus do not represent risk.

Environmental fate	Ecotoxicity	Human health
Environmental fate Moderate alert: Potential for particle bound transport: Medium	Ecotoxicity High alert: Birds chronic ecotoxicity: High; Fish acute ecotoxicity: High; Fish chronic ecotoxicity: High; Daphnia acute ecotoxicity: High; Daphnia chronic ecotoxicity: High; Bees acute contact ecotoxicity: High; Earthworms acute ecotoxicity: High	Human health High alert: Mammals acute toxicity: High; Neurotoxicant

GENERAL INFORMATION

Description

An insecticide used to control a wide range of soil pests including Coleoptera, Lepidoptera and Diptera

Example pests controlled

Springtails; Symphylids; Millipedes; Pygmy beetle; Fire ants; Rootworms; Wireworms; White grubs

Example applications

Sugarbeet; Fodder beet; Cotton; Field corn; Popcorn

Efficacy & activity

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/12/2029

GB LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Hungary/Denmark

Date EC 1107/2009 inclusion expires

31/05/2027

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

Australia; Morocco

Chemical structure

Isomerism

Tefluthrin exhibits stereoisomerism, specifically enantiomerism, due to its chiral cyclopropane ring. The molecule contains two chiral centres at the 1 and 3 positions of the cyclopropane, resulting in the formation of Z-(1R,3R) and Z-(1S,3S) enantiomers. Commercial tefluthrin is typically formulated as a 1:1 racemic mixture of these enantiomers.

Chemical formula

C₁₇H₁₄ClF₇O₂

Canonical SMILES

CC1=C(C(=C(C(=C1F)F)COC(=O)C2C(C2(C)C)C=C(C(F)(F)F)Cl)F)F

Isomeric SMILES

CC1=C(C(=C(C(=C1F)F)COC(=O)[C@H]2[C@H](C2(C)C)/C=C(/C(F)(F)F)\Cl)F)F

International Chemical Identifier key (InChIKey)

ZFHGXWPMULPQSE-SZGBIDFHSA-N

International Chemical Identifier (InChI)

InChI=1S/C17H14ClF7O2/c1-6-11(19)13(21)7(14(22)12(6)20)5-27-15(26)10-8(16(10,2)3)4-9(18)17(23,24)25/h4,8,10H,5H2,1-3H3/b9-4-

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
tefluthrin	Unstated isomer

General status

Pesticide type

Insecticide

Substance groups

Pyrethroid insecticide; Pyrethroid ester insecticide

Minimum active substance purity

920 g kg⁻¹

Known relevant impurities

EU dossier - hexachlorobenzene

Substance origin

Synthetic

Mode of action

Contact and respiratory action with some repellant effects. Sodium channel modulator.

CAS RN

79538-32-2

EC number

616-699-6

CIPAC number

451

US EPA chemical code

128912

PubChem CID

11534837

CLP index number

607-723-00-6

Molecular mass

418.73

PIN (Preferred Identification Name)

rac-(2,3,5,6-tetrafluoro-4-methylphenyl)methyl (1R,3R)-3-[(1Z)-2-chloro-3,3,3-trifluoroprop-1-en-1-yl]-2,2-dimethylcyclopropane-1-carboxylate

IUPAC name

2,3,5,6-tetrafluoro-4-methylbenzyl (1RS,3RS)-3-[(Z)-2-chloro-3,3,3-trifluoroprop-1-enyl]-2,2-dimethylcyclopropanecarboxylate

CAS name

(2,3,5,6-tetrafluoro-4-methylphenyl)methyl (1R,3R)-rel-3-[(1Z)-2-chloro-3,3,3-trifluoro-1-propenyl]-2,2-dimethylcyclopropanecarboxylate

Listed (✓) under

UK Poisons List Order 1972	Rotterdam Convention	Montreal Protocol
XNo The Poisons List Order 1972	XNo Rotterdam Convention	XNo Montreal Protocol
Stockholm Convention	OSPAR	EU Water Framework Directive
XNo Stockholm Convention	XNo OSPAR	XNo EU Water Framework Directive

Relevant Environmental Water Quality Standards

Forever chemical

PFAS

Highly Hazardous Pesticide (HHP)

Type I

Yes []

Type II

Yes [; ; ]

Other status information

Herbicide Resistance Class (HRAC MoA class)

Not applicable

Herbicide Resistance Class (WSSA MoA class)

Not applicable

Insecticide Resistance Class (IRAC MoA class)

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Helicoverpa armigera, Pseudoplusia includens

Physical state

Colourless solid

Commercial

Property

Value

Availability status

Current

Introduction & key dates

1986, registered Belgium; 1989, first registered US

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

Syngenta

Example products using this active

Force ST
Force Evo

Formulation and application details

Often supplied as suspensions for preparation as a seed treatment

Commercial production

The production of tefluthrin involves a multi-step organic synthesis, beginning with the preparation of cyhalothrin acid chloride, a reactive intermediate. This compound undergoes esterification with 4-methyl-2,3,5,6-tetrafluorobenzyl alcohol, forming the ester linkage that defines tefluthrin’s structure. The reaction typically requires a base catalyst and an anhydrous solvent to facilitate the nucleophilic substitution and prevent hydrolysis. Temperature control and purification steps, such as recrystallisation or chromatography, are crucial to isolate the desired product and remove by-products.

Impact on climate of production and use

Data for the amount of life cycle GHGs produced by tefluthrin 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 at pH 7 (mg l⁻¹)

0.016

Low

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

500000

Acetone

500000

Hexane

262000

Methanol

500000

Toluene

Melting point (°C)

44.6

Boiling point (°C)

156

at 1 mmHg

Degradation point (°C)

295

Flashpoint (°C)

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

2.51 X 10⁰⁶

Calculated

Log P

6.4

High

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data - observed in metabolism and farm animal feeding studies

Density (g ml⁻¹)

1.48

Dissociation constant pKa) at 25 °C

Hydrolysis prevents accurate determination

Vapour pressure at 20 °C (mPa)

8.4

Moderately volatile. If applied directly to plants or soil, drift is a concern & mitigation is advisable

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

Moderately volatile

Volatilisation as max % of applied dose lost

From plant surface

60 day

From soil surface

15.2

60 day

Volatilisation is not considered critical for air pollution

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

211.7nm = 25400, 268.3nm = 1190

Surface tension (mN m⁻¹)

69.0

at 20°C 94.9%

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Moderately persistent

DT₅₀ (lab at 20 °C)

Moderately persistent

DT₅₀ (field)

27.1

Non-persistent

DT₉₀ (lab at 20 °C)

73.3

Moderately persistent

DT₉₀ (field)

159.3

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 7-151 days (normalised), DT₉₀ range 43-160 days; field studies DT₅₀ range 9-206 days, DT₉₀ range 31-686 days

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

11.2

Moderately fast

Note

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

Value

Stable

Note

pH sensitive: stable pH 5 and pH 7, DT₅₀ 30 days at pH 9, all at 20 °C

Water-sediment DT₅₀ (days)

Moderately fast

Water phase only DT₅₀ (days)

Moderately fast

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)

1088

Non-mobile

K_oc (mL g⁻¹)

112900

Notes and range

EU dossier K_d range 492-267000 mL g⁻¹, Soils=8

Freundlich

K_f (mL g⁻¹)

3428

Non-mobile

K_foc (mL g⁻¹)

574088

¹/_n

1.1

Notes and range

EU dossier range kf 332-14400; K_foc range 46000-3600000 mL g⁻¹, ¹/_n 0.83-1.23; Soils=8

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

-2.52

Calculated

Low leachability

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

Value

5.35 X 10^-03

Calculated

Note

Estimated concentrations of chemicals with Koc values greater than 9995 ml g⁻¹ are beyond the scope of the regression data used in SCI-GROW development. If there are concerns for such chemicals, a higher tier groundwater exposure assessment should be considered, regardless of the concentration returned by SCI-GROW

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Non-mobile

Calculated

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

22.56

Calculated using the Atkinson method. Assumed 0.5E+06 OH/cm³, 24 hr. EU trigger for long-range transport is DT₅₀ in air <2 days.

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

1400

Threshold for concern

CT₅₀ (days)

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

(1RS,3RS)-3-((Z)-2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylic acid (Ref: PP890)

Minor fraction

0.071

2,3,5,6-tetrafluoro-4-methylbenzoic acid

Anaerobic

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

2,3,5,6-tetrafluoro-4-methylbenzyl (Z) (1R,2R,3R; 1S,2S,3S)-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2-hydroxymethyl-2-methylcyclopropanecarboxylic acid (Ref: R177540)

tefluthrin Compound IX

Rat

3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2-hydroxymethylcyclopropanecarboxylic acid (Ref: R173948)

tefluthrin Compound X1

Rat; Plant

3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-1-methylcyclopropane-1,2-dicarboxylic acid

tefluthrin Compound XII

Plant

2,3,5,6-tetrafluoro-4-hydroxymethyl benzoic acid (Ref: R173204)

tefluthrin Compound V1

Animal

2,3,5,6-tetrafluoroterephthalic acid

tefluthrin Compound IV

Surface water

0.07

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

21.8

Rat

High

Mammals - Short term dietary NOEL

(mg kg⁻¹)

> 75

Rat

High

(ppm diet)

> 150

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

23.4

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 267

Passer domesticus

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

> 179 mg kg bw⁻¹ day⁻¹

Anas platyrhynchos

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

≥ 2

Colinus virginianus NOEL

High

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹ dw soil)

1.0

Eisenia foetida corr

High

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

0.16

Eisenia foetida corr

Moderate

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect
Carbon mineralisation: No significant adverse effect

Dose: 0.75 kg ha⁻¹ 28 Day

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

30.0

Folsomia candida corr

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)

0.28

Apis mellifera

High

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

1.88

Apis mellifera

Moderate

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)

0.00006

Oncorhynchus mykiss

High

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

0.000004

Pimephales promelas 1 year

High

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

0.002

Danio rerio EC₅₀ Embryo

High

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

0.00007

Daphnia magna

High

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

0.000008

Daphnia magna

High

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

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

0.00005

Americamysis bahia

High

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

> 0.0025

Chironomus riparius 48 hr EC₅₀

High

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

0.47

Chironomus riparius Reproduction

Moderate

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) (72 hr ErC₅₀, Static)

> 1.05

Raphidocelis subcapitata

Moderate

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

0.18

Unknown species

Moderate

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves – Acute EC₅₀, immobility (mg l⁻¹)

> 1.0

Crassostrea gigas Embryo

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)

21.8

Rat

High

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

177

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.037

Rat 4 hr (nose only)

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

0.005

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

0.005

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

0.0015

Dermal penetration studies (%)

0.12

Dangerous Substances Directive 76/464

List II

Exposure Routes

Public

No unacceptable risks to bystanders identified

Occupational

No unacceptable risks to operators or other workers identified with PPE/PPC

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

GB MRL levels for some commodities subject to change in late 2021

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Mammalian dose elimination route and rate

Health issues

Specific human health issues (hazard-based)

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Highly toxic
Possible thyroid and CNS toxicant

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 6.1
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H300, H310, H330
Environment: H400, H410

WHO Classification

Ib (Highly hazardous)

UN Number

UN2811

Waste disposal & packaging

Packaging Group II (moderate danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

tefluthrin

French

tefluthrine

German

Tefluthrin

Danish

tefluthrin

Italian

teflutrin

Spanish

teflutrin

Greek

Polish

teflutryna

Swedish

teflutrin

Hungarian

teflutrin

Dutch

Norwegian

Record last updated:	22/10/2025
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