Fenpyroximate (Ref: NNI 850)

Fenpyroximate (Ref: NNI 850)	Last updated: 22/05/2025
(Not known by any other names)

SUMMARY

Fenpyroximate is a pyrazolium insecticide used to control important phytophagous mites in fruit and other crops. It has a low aqueous solubility and is not considered a volatile substance. Whilst it is not normally persistent in water bodies, it can be persistent in soils depending upon local conditions. Based on its physico-chemical properties fenpyroximate is not expected to leach to groundwater. Toxicity to biodiversity tends to be considered high to moderate. It has moderate oral toxicity to humans and there are concerns that it may be a developmental/reproduction toxin.

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
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	Human health High alert: Mammals chronic toxicity: High; Reproduction/development effects

GENERAL INFORMATION

Description

A acaricide used to control important phytophagous mites in fruit

Example pests controlled

Mites including Tetranychidae; Tarsonemidae; Tenuipalpidae; Eriophyidae

Example applications

Fruit including citrus, apples, pears, peaches, grapes, strawberries, currants; Tree nuts; Ornamentals; Sugarbeet

Efficacy & activity

Demonstrated to offer equivalent or greater benefit than comparable substances via field trials.

Availability status

Current

Introduction & key dates

1990, first reported; 1991, first introduced

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

30/04/2029

GB LERAP status

No data

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Austria/Denmark

Date EC 1107/2009 inclusion expires

15/06/2026

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; Egypt

Chemical structure

Isomerism

Isomeric existing in the E- and Z-forms.

Chemical formula

C₂₄H₂₇N₃O₄

Canonical SMILES

CC1=NN(C(=C1C=NOCC2=CC=C(C=C2)C(=O)OC(C)(C)C)OC3=CC=CC=C3)C

Isomeric SMILES

CC1=NN(C(=C1/C=N/OCC2=CC=C(C=C2)C(=O)OC(C)(C)C)OC3=CC=CC=C3)C

International Chemical Identifier key (InChIKey)

YYJNOYZRYGDPNH-MFKUBSTISA-N

International Chemical Identifier (InChI)

InChI=1S/C24H27N3O4/c1-17-21(22(27(5)26-17)30-20-9-7-6-8-10-20)15-25-29-16-18-11-13-19(14-12-18)23(28)31-24(2,3)4/h6-15H,16H2,1-5H3/b25-15+

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
fenpyroximate	-

General status

Pesticide type

Acaricide; Insecticide

Substance groups

Pyrazolium insecticide; Pyrazolium acaricide

Minimum active substance purity

960 g kg⁻¹

Known relevant impurities

EU 2019 RAR dossier - 1,3-dimethyl-5-phenoxy-4-pyrazolecarbaldehyde oxime (NN-4) < 1 g kg⁻¹; tert-butyl-4-chloromethylbenzoate (NN-9) < 1.4 g kg⁻¹, methanol < 1.0 g.kg

Substance origin

Synthetic

Mode of action

Contact action. Mitochondrial complex I electron transport inhibitor.

CAS RN

134098-61-6

EC number

603-792-1

CIPAC number

695

US EPA chemical code

129131

PubChem CID

9576412

CLP index number

607-713-00-1

Molecular mass

421.49

PIN (Preferred Identification Name)

tert-butyl 4-[({[(E)-(1,3-dimethyl-5-phenoxy-1H-pyrazol-4-yl)methylidene]amino}oxy)methyl]benzoate

IUPAC name

tert-butyl (E)-α-(1,3-dimethyl-5-phenoxypyrazol-4-ylmethyleneaminooxy)-p-toluate

CAS name

1,1-dimethylethyl 4-((((E)-((1,3-dimethyl-5-phenoxy-1H-pyrazol-4-yl)methylene)amino)oxy)methyl)benzoate

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Not applicable

Herbicide Resistance Class (WSSA MoA class)

Not applicable

Insecticide Resistance Class (IRAC MoA class)

21A

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Tetranychus kanzawai, Tetranychus urticae

Physical state

White crystalline powder

Formulations

Property

Value

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

Certis
Farma-Chem SA
Ypsilon SA

Example products using this active

Fenpyroximate 5SC
Edonis
Kiron
Sequel
Acaritan
Danitron 5 SC

Formulation and application details

Often supplied as a soluble concentrate which is mixed with water and applied as a spray

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.021

Low

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

116000

Acetone

16500

Ethanol

13400

Methanol

193000

Xylene

Melting point (°C)

102.0

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

215

Flashpoint (°C)

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

5.01 X 10⁰⁵

Calculated

Log P

5.70

High

Fat solubility of residues

Solubility

Soluble

Data type

Regulatory data - observed in metabolism and farm animal feeding studies

Density (g ml⁻¹)

1.25

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.00921

Low volatility

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

0.0168

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Acidic: 200nm=45400, 235.5nm=22850, 258nm=19260
Neutral; 200nm=47270, 235nm=22510, 258nm=19520
Basic: 218.5nm=21310, 235.5nm=22610, 258nm=19590

Surface tension (mN m⁻¹)

72.2

at 20°C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

135.1

Persistent

DT₅₀ (lab at 20 °C)

135.1

Persistent

DT₅₀ (field)

6.8

Non-persistent

DT₉₀ (lab at 20 °C)

358

Persistent

DT₉₀ (field)

31.7

DT₅₀ modelling endpoint

Note

EU 2019 dossier lab studies DT₅₀ (normalised) range 36.1-282 days, DT₉₀ (measured) range 120-790 days,Soils=5, Field studies DT₅₀ (normalised) range 2.8-23.7 days, DT₉₀ (measured) range 9,.32-78.6 days, Soils=4; Other studies: Lab DT₅₀ range 26-50 days (B5)

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

1.36

Note

Published literature RL₅₀ range 1.36-3.2 days, 5 field crops, various matrices, n=9

Aqueous photolysis DT₅₀ (days) at pH 7

Value

0.1

Fast

Note

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

Value

9.4

Non-persistent

Note

pH sensitive: DT₅₀ 7.5 days at pH 5, 9.2 days at pH 9

Water-sediment DT₅₀ (days)

33.8

Moderately fast

Water phase only DT₅₀ (days)

2.91

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)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

629.2

Non-mobile

K_foc (mL g⁻¹)

4838

¹/_n

0.95

Notes and range

EU 2019 dossier K_f range 122-2253 mL g⁻¹, K_foc range 11091-72677 mL g⁻¹, ¹/_n range 0.l849-1.03, Soils=5

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

0.26

Calculated

Low leachability

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

Value

5.73 X 10^-03

Calculated

Note

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

35.3

Calculated using the Atkinson method. Assumed 6.5E+05 OH/cm³, 12 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

1601

Whole fish

Threshold for concern

CT₅₀ (days)

5.3

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

1,3-dimethyl-5-phenoxypyrzole-4-carbonitrile (Ref: M-11)

Minor fraction

0.088

1,3-dimethyl-5-phenoxypyrazole-4-carboxylic acid

Minor fraction

0.0074

(E)-4-((1,3-dimethyl-5-phenocypyrazole-4-yl)methyleneaminooxy-methyl)benzoic acid (Ref: M-3)

Major fraction

0.108

Known groundwater metabolites

None

Other known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

245

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

1.3

Rat

High

(ppm diet)

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

Rat Reproductive NOAEL

High

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Colinus virginianus

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

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

3.65

Anas platyrhynchos NOAEDD

High

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

34.7

Eisenia foetida corr

Moderate

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

2.71

Eisenia foetida EC10 corr

Moderate

Soil micro-organisms

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

Dose: 22.5 kg ha⁻¹ 28 Day

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

25.0

Folsomia candida corr

Non-target plants

Honeybees (Apis spp.)

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

> 15.8

Apis mellifera

Moderate

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

> 118.5

Apis mellifera

Low

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

Chronic as 10-day LDD₅₀ µg bee⁻¹ day⁻¹

> 1.129

Apis mellifera

Notes

[USEPA LD50 contact reported as 479.8 ug/bee]

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) as Mortality LR₅₀ g ha⁻¹

59.7

Coccinella septempunctata Larva

Beneficial insects (Lacewings) as Mortality LR₅₀ g ha⁻¹

> 125

Chrysoperla carnea Larva

Beneficial insects (Parasitic wasps) as Mortality LR₅₀ g ha⁻¹

> 2.5

Aphidius rhopalosiphi

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹

> 2.5

Typhlodromus pyri

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)

0.00105

Oncorhynchus mykiss

High

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

0.00019

Oncorhynchus mykiss

High

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

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

0.00328

Daphnia magna

High

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

0.00016

Daphnia magna

High

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)

0.01

Chironomus riparius

Moderate

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

0.81

Chironomus riparius

Moderate

Aquatic plants (free-floating, growth) - Acute 7 day EC₅₀, biomass (mg l⁻¹)

Aquatic plants (rooted, growth) - Acute 14 day EC₅₀, biomass (mg l⁻¹)

Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)

0.0094

Desmodesmus subspicatus

High

Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)

0.01

Scenedesmus subspicatus

Moderate

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)

245

Rat

Moderate

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.33

Rat 4 hr (nose only)

Other Mammal toxicity endpoints

Intravenous LD₅₀ < 0.69 mg kg⁻¹

Rat

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

0.01

Rat SF=100

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

0.02

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

0.006

Dog SF=100

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

0.005

Dermal penetration studies (%)

2.0-9.0

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Acceptable for registered uses

Occupational

Possible risk to operators and other farm workers identified - PPE/PPC advised

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

General human health issues

No further information available

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 9
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H301, H330, H317
Environment: H400, H410

WHO Classification

II (Moderately hazardous)

UN Number

UN3077

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

Chemically stable under standard ambient conditions

TRANSLATIONS

Language

Name

English

fenpyroximate

French

fenpyroximate

German

Fenpyroximat

Danish

fenpyroximat

Italian

fenprioximate

Spanish

fenpiroximato

Greek

Polish

fenpiroksymat

Swedish

fenpyroximat

Hungarian

fenpiroximat

Dutch

Norwegian

fenpyroksimat

Record last updated:	22/05/2025
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