Zeta-cypermethrin (Ref: FMC 56701)

Zeta-cypermethrin (Ref: FMC 56701)	Last updated: 05/09/2025
(Also known as: zetacypermethrin; z-cypermethrin ; F 56701)

GENERAL INFORMATION

Description

An insecticide used to control beetles, aphids and Lepidoptera in a range of crops

Examples of veterinary uses

Examples of species treated

Approval status

VMR 2013/2033 approval status (GB/UK)

EU Regulatory approval status

Chemical structure

Isomerism

Cypermethrin is a chiral molecule and consists of eight isomers, four cis and four trans. Zeta-cypermethrin is a mixture of stereoisomer pairs

Chemical formula

C₂₂H₁₉Cl₂NO₃

Canonical SMILES

CC1(C(C1C(=O)OC(C#N)C2=CC(=CC=C2)OC3=CC=CC=C3)C=C(Cl)Cl)C

Isomeric SMILES

CC1(C(C1C(=O)O[C@H](C#N)C2=CC(=CC=C2)OC3=CC=CC=C3)C=C(Cl)Cl)C

International Chemical Identifier key (InChIKey)

KAATUXNTWXVJKI-QPIRBTGLSA-N

International Chemical Identifier (InChI)

InChI=1S/C22H19Cl2NO3/c1-22(2)17(12-19(23)24)20(22)21(26)28-18(13-25)14-7-6-10-16(11-14)27-15-8-4-3-5-9-15/h3-12,17-18,20H,1-2H3

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
zeta-cypermethrin	-

General status

Veterinary substance type

Substance groups

Pyrethroid insecticide; Pyrethroid ester insecticide

Minimum active substance purity

850 g kg⁻¹

Known relevant impurities

EU dossier - toluene <2g kg⁻¹, tars 12.5 g kg⁻¹

Substance origin

Synthetic

Mode of action

Contact and stomach action. Acts mainly on the nervous system. Sodium channel modulator.

Molecular targets

CAS RN

1315501-18-8

Alternative/old CAS RN

97955-44-7

EC number

257-842-9

CIPAC number

733

US EPA chemical code

109702/129064

PubChem CID

12617362

Therapeutic Class

ATCvet Code

Controlled Drug?

Regulation 37/2010 MRL Classification

Molecular mass

416.31

PIN (Preferred Identification Name)

mixture of the stereoisomer pairs (S)-cyano(3-phenoxyphenyl)methyl (1R*,3R*)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate and (S)-cyano(3-phenoxyphenyl)methyl (1R*,3S*)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate in the ratio range 45–55 to 55–45 respectively

IUPAC name

mix of (S)-α-cyano-3-phenoxybenzyl (1RS,3RS;1RS,3SR)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate

CAS name

(S)-cyano(3-phenoxyphenyl)methyl 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate

Forever chemical

Other status information

Relevant Environmental Water Quality Standards

UK Environment Agency non-statutory standard for the protection of aquatic life in freshwater and saltwater annual average 0.0002 µg l⁻¹, max acceptable conc 0.002 µg l⁻¹
UK statutory standard for water quality: ‘Good’ for fresh, transitional & saltwater: 0.1 ng l⁻¹ as annual mean conc, 0.4 ng l⁻¹ 95th percentile

Physical state

Pale yellow viscous liquid

Related substances & organisms

cypermethrin

alpha-cypermethrin

beta-cypermethrin

theta-cypermethrin

Commercial

Property

Value

Availability status

Current

Introduction & key dates

1984, introduced

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

AgriGuard
BASF
Belchim

Example products using this active

Fury 10EW
Minuet
Synphony
Holster
Mustang

Formulation and application details

Often supplied as oil in water emulsions that are mixed with water and used as a spray

Commercial production

The production of zeta-cypermethrin involves the synthesis of cypermethrin followed by an epimerization process to selectively enrich the S-enantiomer of the alcohol moiety. This process adjusts the cis/trans ratio in the cyclopropane ring to achieve the desired stereoisomeric composition. Cypermethrin is produced through a multi-step chemical synthesis that begins with chrysanthemic acid, a compound structurally related to natural pyrethrins found in chrysanthemum flowers. The acid is chemically modified to enhance its stability and insecticidal potency. The key step involves esterification with a cyanophenoxybenzyl alcohol derivative, forming the active cypermethrin molecule—a synthetic pyrethroid.

Impact on climate of production and use

Precise life cycle emissions are unpublished but Audsley et al. (2009) reported that it takes 615 MJ of energy per kg produced. This is equivalent to approximately 42.4 kg CO₂e. There will also be emissions associated with packaging, transport and application.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.039

Low

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

40120

n-Heptane

1000000

p-Xylene

1000000

Acetone

1000000

Ethyl acetate

Melting point (°C)

-3

Boiling point (°C)

360

Degradation point (°C)

Flashpoint (°C)

181

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

3.98 X 10⁰⁶

Calculated

Log P

6.6

(EU dossier: LogP 5-6 at pH 2 24 °C; A4)

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.24

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

2.53 X 10^-04

Low volatility

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

2.31 X 10^-03

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Neutral solution: 278nm = 2468, 290nm = 765
Acidic solution 278nm = 2472, 290nm = 765
Basic solution: hydrolysis product formed with maxima = 308 nm

Surface tension (mN m⁻¹)

59.5

at 25°C 90% soln

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)

Moderately persistent

DT₅₀ (field)

Non-persistent

DT₉₀ (lab at 20 °C)

56.7

Moderately persistent

DT₉₀ (field)

Note

Earlier EU dossier lab studies DT₅₀ range 6-105 days (A3), DT₉₀ range 34-80.5 days, Current dossier field studies DT₅₀ 6-24 days S. France, Italy and Germany;Other data source: 14 days (DW4)

Manure DT₅₀ (days)

Aqueous photolysis DT₅₀ (days) at pH 7

Value

3.05

Moderately fast

Note

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

Value

Non-persistent

Note

pH sensitive: Stable at pH 4, variable at pH 9

Water-sediment DT₅₀ (days)

Fast

Water phase only DT₅₀ (days)

0.1

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)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

1033

Non-mobile

K_foc (mL g⁻¹)

121786

¹/_n

1.30

Notes and range

EU dossier K_f range 416-1897 mL g⁻¹, K_foc range 18326-285562 mL g⁻¹, ¹/_n range 1.15-1.47, Soils=4

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

-1.09

Calculated

Low leachability

Bio-concentration factor

BCF (l kg⁻¹)

356

Whole fish

Threshold for concern

CT₅₀ (days)

1.2

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid

Major fraction

0.242

3-phenoxybenzoic acid

Minor fraction

0.084

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

(3-phenoxyphenyl)methanol

mPBAcohol

Plant; Animal

3-phenoxybenzaldehyde

mPBAldehyde

Plant

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

Rat

High

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

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

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 5124

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 601 mg kg bw⁻¹ day⁻¹

Anas platyrhynchos

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

2.15

Colinus virginianus

High

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

37.5

Eisenia foetida corr

Moderate

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

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect at 59 days
Carbon mineralisation: No significant adverse effect at 64 days

Dose: 2 mg kg⁻¹ soil

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)

0.002

Apis mellifera

High

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

0.044

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) as Mortality LR₅₀ mL/ha, Extended lab test

5.48

Aphidius rhopalosiphi Adult

Moderate

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹ 7 day, Std lab test

23.18

Typhlodromus pyri

Moderate

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)

0.00069

Oncorhynchus mykiss

High

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

0.000585

Oncorhynchus mykiss

High

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

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

0.00014

Daphnia magna

High

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

0.00001

Daphnia magna

High

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

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

0.0128

Americamysis bahia

High

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

0.001

Chironomus riparius

High

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) (96 hr EC₅₀)

> 1.0

Raphidocelis subcapitata

Moderate

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)

Rat

High

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

1.26

Rat

Other Mammal toxicity endpoints

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

0.04

Dog SF=200

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

0.125

Rat SF=100

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

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

0.02

Dog SF=400

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders identified

Occupational

Possible risk of exposure to operators or other workers identified - PPE/PPC advised

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

US EPA - possible human carcinogen

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 6.1

CLP classification 2013

Health: H302, H317, H332
Environment: H410

WHO Classification

II (Moderately hazardous)

UN Number

UN2902

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

zeta-cypermethrin

French

zetacypermethrine

German

zeta-Cypermethrin

Danish

zeta-cypermethrin

Italian

zeta-cipermetrina

Spanish

zeta-cipermetrin

Greek

Polish

zeta-cypermetryna

Swedish

Hungarian

zeta-cypermethrin

Dutch

Norwegian

Record last updated:	05/09/2025
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