Chlorfenapyr (Ref: MK 242)

Chlorfenapyr (Ref: MK 242)	Last updated: 22/05/2025
(Also known as: AC 303630; CL 303630)

SUMMARY

Chlorfenapyr is a broad-spectrum insecticide. It has a low aqueous solubility, low volatility and, based on its chemical properties, would not normally be expected to leach to groundwater. It is not usually persistent in soil or water systems. It has a moderate mammalian oral toxicity but no other data on human health impact has been identified. There are also gaps in ecotoxicological data but it is known to be highly toxic to birds, fish and aquatic invertebrates.

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 Warning: Significant data are missing	Ecotoxicity High alert: Birds acute ecotoxicity: High; Fish acute ecotoxicity: High; Fish chronic ecotoxicity: High; Daphnia acute ecotoxicity: High; Daphnia chronic ecotoxicity: High; Bees acute unknown ecotoxicity: High	Human health High alert: Mammals acute toxicity: High

GENERAL INFORMATION

Description

A proinsecticide used to control many insects and mites including those resistant to carbamate, organophosphate and pyrethroid compounds

Example pests controlled

Spider mites; Caterpillars; Thrips; Fungus gnats; Public health applications including termites, cockroaches, ants, bedbugs, flies and spiders

Example applications

Greenhouse ornamentals

Efficacy & activity

Availability status

Current

Introduction & key dates

1996, first registered Japan; 2001, first registered USA

GB regulatory status

GB COPR regulatory status

Not approved

Date COPR inclusion expires

Expired

GB LERAP status

No UK approval for use as a plant protection agent

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

Spain

Date EC 1107/2009 inclusion expires

Expired

EU Candidate for substitution (CfS)

Not applicable

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

Chemical structure

Isomerism

None

Chemical formula

C₁₅H₁₁BrClF₃N₂O

Canonical SMILES

CCOCN1C(=C(C(=C1C(F)(F)F)Br)C#N)C2=CC=C(C=C2)Cl

Isomeric SMILES

International Chemical Identifier key (InChIKey)

CWFOCCVIPCEQCK-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C15H11BrClF3N2O/c1-2-23-8-22-13(9-3-5-10(17)6-4-9)11(7-21)12(16)14(22)15(18,19)20/h3-6H,2,8H2,1H3

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
chlorfenapyr	-

General status

Pesticide type

Insecticide; Acaricide; Miticide; Other substance

Other bioactivity & uses

Biocide; Preservative; Slimicide

Substance groups

Pyrrole insecticide; Pyrrole acaricide

Minimum active substance purity

> 940 g kg⁻¹

Known relevant impurities

Substance origin

Synthetic

Mode of action

Limited systemic activity, mainly stomach but some contact action. Uncoupler of oxidative phosphorylation.

CAS RN

122453-73-0

EC number

602-782-4

CIPAC number

570

US EPA chemical code

129093

PubChem CID

91778

CLP index number

608-034-00-3

Molecular mass

407.62

PIN (Preferred Identification Name)

4-bromo-2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile

IUPAC name

4-bromo-2-(4-chlorophenyl)-1-ethoxymethyl-5-trifluoromethyl-1H-pyrrole-3-carbonitrile

CAS name

4-bromo-2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile

Other status information

Chemical subject to PIC regulations; Some applications are approved under GB Biocides Products Regulations

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)

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Earias vittella, Tetranychus urticae

Physical state

White powdery solid

Related substances & organisms

tralopyril

Formulations

Property

Value

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

BASF
AgroCare
FCC
Nippon soda

Example products using this active

Pirate
Pylon
Shark
Arg Chlorfenapyr Tgai
Phantom Termiticide
Kotetsu

Formulation and application details

Usually supplied as suspension concentrate

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.112

at 25 °C

Low

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

8900

Hexane

70900

Methanol

754000

Toluene

1410000

Dichloromethane

Melting point (°C)

101

Boiling point (°C)

Degradation point (°C)

183

Flashpoint (°C)

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

1.62 X 10⁰⁵

Calculated

Log P

5.21

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.53

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

9.81 X 10^-03

at 25 °C

Low volatility

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

5.81 X 10^-04

at 25 °C

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)

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

1.4

Non-persistent

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Dissipation rate RL₅₀ (days) on plant matrix

Value

3.28

Note

Published literature RL₅₀ range 2.85-3.7 days, 3 crops, various matrices, n=3

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

3.7

Note

Published literature RL₅₀ range 1.4-7.0 days, 8 field and undercover grown crops, various matrices, n=11

Aqueous photolysis DT₅₀ (days) at pH 7

Value

6.2

Moderately fast

Note

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

Value

Stable

Note

Stable pH 4 to pH 9

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)

12000

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

-0.01

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

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

Not available

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

2-pyrroline-3-carbonitrile,4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-chlorfenapyr

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

4-bromo-2-(p-chlorophenyl)-5-(carboxylic)- pyrrole-3-carbonitrile (Ref: AC 322250)
Note: Rat LD50 = 2500 mg/kg bw

Animal

2-(4-chlorophenyl)-5-hydroxyl-4-oxo-5-(trifluoromethyl)-3-pyrrole-3-carbonitrile (Ref: AC 325195)
Note: Rat LD50 = 776 mg/kg bw

Animal

2-(4-chlorophenyl)-1-(ethoxymethyl)-5-(trifluoromethyl) -1H-pyrrole-3-carbonitrile (Ref: AC 312094)
Note: Rat LD50 > 5000 mg/kg bw

Animal, Plant

tralopyril (Ref: CL 303268)
Note: Rat LD50 = 27 mg/kg bw

4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile

Animal, Plant

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

Mouse

High

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)

Colinus virginianus

High

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

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)

0.12

Apis mellifera

High

Chronic

Notes

[The residual time to 25% mortality (RT25) value for honeybees is 3 hrs - USEPA data]

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)

> 1.75

Osmia excavata

Moderate

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) as Mortality, Contact LC₅₀ ppm

> 3.65

Chrysoperla carnea Instar

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)

0.007

Oncorhynchus mykiss

High

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

> 0.00871

Cyprinodon variegatus 33 day

High

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

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

0.0061

Daphnia magna

High

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

0.00357

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)

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

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)

Algae - Chronic 96 hour NOEC, growth (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)

Mouse

High

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

2000

Rabbit

Mammals - Inhalation LC₅₀ (mg l⁻¹)

1.9

Rat

Other Mammal toxicity endpoints

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

0.015

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

0.015

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 II

Exposure Routes

Public

Occupational

Occupational exposure may occur through dermal contact

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

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

Possile testicular and uterine toxicant
US EPA - some weak evidence to suggest possible human carcinogen

Handling issues

Property

Value and interpretation

General

No information available

CLP classification 2013

Health: H302, H331
Environment: H400, H410

WHO Classification

II (Moderately hazardous)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

chlorfenapyr

French

chlorfénapyr

German

Chlorfenapyr

Danish

chlorfenapyr

Italian

clorfenapir

Spanish

clorfenapir

Greek

chlorfenapyr

Polish

chlorofenapir

Swedish

Hungarian

Dutch

chloorfenapyr

Norwegian

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