Fenoxaprop-P-ethyl (Ref: AE F046360)

Fenoxaprop-P-ethyl (Ref: AE F046360)	Last updated: 26/08/2024
(Also known as: HOE 046360)

SUMMARY

Fenoxaprop-P-ethyl is a post-emergence herbicide used to control annual and perennial grasses. Fenoxaprop is a chiral molecule existing in the R- and S-forms. Fenoxaprop-P is the R-isomer. It has a low aqueous solubility and a low volatility. It tends not to be persistent in soils but, under certain conditions, may persist in water systems. Fenoxaprop-P-ethyl has a low acute oral toxicity for birds and honeybees; a moderate toxicity for mammals, earthworms, fish and aquatic invertebrates. Oral toxicity for humans is in the high-moderate class. It is also a recognised irritant.

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 Low alert: Non-persistent; GUS: Low leachability; Drainflow: Non-mobile; Potential for particle bound transport: Low	Ecotoxicity Moderate alert: Birds chronic ecotoxicity: Moderate; Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Bees acute contact ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate; Earthworms chronic ecotoxicity: Moderate	Human health High alert: Mammals chronic toxicity: High Warning: Significant data are missing

GENERAL INFORMATION

Description

A post-emergence herbicide used to control annual and perennial grasses

Example pests controlled

Goosegrass; Grabgrass; Bermuda grass; Barnyard grass; Foxtails

Example applications

Turf; Ornamentals; Rice; Cereals including wheat, barley, rye, triticale

Efficacy & activity

Efficiacy demonstrated via field trials and extensive global use

Availability status

Current

Introduction & key dates

1989, first reported

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

Austria/Finland

Date EC 1107/2009 inclusion expires

15/08/2025

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

Fenoxaprop is a chiral molecule existing in the R- and S-forms. Fenoxaprop-P is the R-isomer.

Chemical formula

C₁₈H₁₆ClNO₅

Canonical SMILES

CCOC(=O)C(C)OC1=CC=C(C=C1)OC2=NC3=C(O2)C=C(C=C3)Cl

Isomeric SMILES

CCOC(=O)[C@@H](C)OC1=CC=C(C=C1)OC2=NC3=C(O2)C=C(C=C3)Cl

International Chemical Identifier key (InChIKey)

PQKBPHSEKWERTG-LLVKDONJSA-N

International Chemical Identifier (InChI)

InChI=1S/C18H16ClNO5/c1-3-22-17(21)11(2)23-13-5-7-14(8-6-13)24-18-20-15-9-4-12(19)10-16(15)25-18/h4-11H,3H2,1-2H3/t11-/m1/s1

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Aryloxyphenoxypropionate herbicide

Minimum active substance purity

920 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Selective, systemic with contact action. Acetyl CoA carboxylase inhibitor (ACCase) - distrupts fatty acid biosynthesis and lipid formation.

CAS RN

71283-80-2

EC number

No data found

CIPAC number

484

US EPA chemical code

PubChem CID

91707

CLP index number

607-707-00-1

Molecular mass

361.78

PIN (Preferred Identification Name)

ethyl (2R)-2-{4-[(6-chloro-1,3-benzoxazol-2-yl)oxy]phenoxy}propanoate

IUPAC name

(R)-2[4-[(6-chloro-2-benzoxazolyl)oxy]-phenoxy]-propanoic acid

CAS name

(R)-2-(4-((6-chloro-1,3-benzoxazolyl)oxy)phenoxy)propanoate ethyl

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Class (HRAC MoA class)

Herbicide Resistance Class (WSSA MoA class)

Insecticide Resistance Class (IRAC MoA class)

Not applicable

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Many recorded cases, Alopecurus myosuroides, Avena fatua, Avena sterilis, Echinochloa colona

Physical state

White solid

Related substances & organisms

fenoxaprop

fenoxaprop-ethyl

fenoxaprop-P

Formulations

Property

Value

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

Bayer CropScience
Headland

Example products using this active

Cheetah Super
Foxtrot EW
Tigress Ultra
Triumph
Puma S
Oskar
Puma extra

Formulation and application details

Often supplied as an oil emulsion 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)

0.43

Low

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

7000

n-Hexane

400000

Acetone

43100

Methanol

380000

Ethyl acetate

Melting point (°C)

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

330

Flashpoint (°C)

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

3.80 X 10⁰⁴

Calculated

Log P

4.58

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.32

Dissociation constant pKa) at 25 °C

0.18

Very strong acid

Vapour pressure at 20 °C (mPa)

6.50 X 10^-03

Low volatility

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

5.5 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

239nm = 22862, 278nm = 7980, 291nm = 1488

Surface tension (mN m⁻¹)

70.5

at 20 °C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

0.36

Non-persistent

DT₅₀ (lab at 20 °C)

0.36

Non-persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

2.4

Non-persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU 2018 dossier lab studies DT₅₀ (normalised) range 0.07-1.4 days, DT₉₀ range 0.24-6.1 days, Soils=8; Other sources: 10.5 days (DW4)

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

1.8

Note

Published literature RL₅₀ range 1.5-2.1 days, 2 field crops, various matrices, n=3

Aqueous photolysis DT₅₀ (days) at pH 7

Value

105

Stable

Note

DT₅₀ 57.5 days at pH 5 (sterile buffer), 7.2 days at pH 9 (natural waters)

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

Value

22.2

Non-persistent

Note

pH sensitive: DT₅₀ 2.8 days at pH 4, 19.2 days at pH 5, 0.7 days at pH 9, all at 25 °C

Water-sediment DT₅₀ (days)

0.1

Fast

Water phase only DT₅₀ (days)

0.1

Fast

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)

278.5

Non-mobile

K_oc (mL g⁻¹)

11354

Notes and range

EU 2018 dossier K_d range 57-443 mL g⁻¹; K_oc range 5419-26200; Soils=8, for FOCUS GW studies use K_oc = 6000

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

0.02

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

Low

Calculated

Potential for loss via drain flow

Non-mobile

Calculated

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

3.83

Calculated using the Atkinson method. Assumed 1.5E+06 OH/cm³, 12 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

338

Whole fish

Threshold for concern

CT₅₀ (days)

0.4

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

fenoxaprop-P (Ref: AE-F088406)

Major fraction

0.858

chlorobenzoxazolone (Ref: AE-F054014)

Major fraction

0.191

hydroxy phenoxy propionic acid (Ref: AE F020686)

Minor fraction

Anaerobic

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

mercapturic acid

Rat (Urine)

6-hydroxy-2,3-dyhydro-benzoxazol-2-one (Ref: AE 0316854)

Water (Photolysis)

6-chloro-2,3-dihydrobenzoxazol-2-one

Plant

3-acetyl-6-chloro-2,3-dihydrobenzoxazol-2-one

Plant

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 300

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

> 0.7

Rat

High

(ppm diet)

> 10

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

8.8

Unknown species Reproductive NOAEL

High

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2000

Coturnix japonica

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

> 401 mg kg bw⁻¹ day⁻¹

Coturnix japonica

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

30.8

Colinus virginianus NOAEL

Moderate

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

> 500

Eisenia foetida corr

Moderate

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

>= 28.0

Eisenia foetida corr

Moderate

Soil micro-organisms

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

Dose: 0.56 mg kg⁻¹ soil 28 Day

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

>= 500

Folsomia candida corr

Non-target plants

8.14

Zea mais
Vegetative vigour, ER₅₀
as g ha⁻¹

> 1200

10 species non-target terrestrial plants
Seedling emergence, ER₅₀
as mL formulation ha⁻¹

Honeybees (Apis spp.)

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

> 36.4

Apis mellifera

Moderate

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

> 109.5

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

10.06

Apis mellifera

Bumblebees (Bombus spp.)

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

> 100

Bombus terrestris

Low

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

> 124.5

Bombus terrestris

Low

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) as Mortality LR₅₀ as g ha⁻¹

> 82.2

Chrysoperla carnea

Beneficial insects (Parasitic wasps) as Mortality LR₅₀ g ha⁻¹ 48 hr

46.4

Aphidius rhopalosiphi Adult

Beneficial insects (Predatory mites) as Mortality LR₅₀ g ha⁻¹ 7 day

> 82.2

Typhlodromus pyri Protonymph

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)

0.19

Lepomis macrochirus

Moderate

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

0.036

Oncorhynchus mykiss

Moderate

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

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

> 1.06

Daphnia magna

Moderate

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

0.22

Daphnia magna

Moderate

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)

0.2

Chironomus riparius Emergence

Moderate

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

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

>= 2.76

Lemna gibba

Moderate

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

0.54

Scenedesmus subspicatus

Moderate

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

0.32

Unknown species

Moderate

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves – Acute EC₅₀ development (mg l⁻¹)

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)

> 300

Rat

Moderate

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

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 1.22

Rat (nose only)

Other Mammal toxicity endpoints

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

0.01

Dog SF=100

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

0.1

Rat SF=100

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

0,.1

Rat SF=100

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

0.014

Rat SF=100

Dermal penetration studies (%)

0.7-27.0

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Negligible risk to bystanders
Minimal risk of dietary exposure

Occupational

Risk of dermal absorption during handling
Risk of exposure acceptable under label recommendations for use for personal protection clothing and equipment

MRLs

European

EU MRL pesticide database

Great Britain

GB MRL Register

Notes

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

0.1

EU Dir 89/778/EC limit

Mammalian dose elimination route and rate

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

No data found

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

General human health issues

Possible liver and kidney toxicant

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: H317, H373
Environment: H400, H410

WHO Classification

III (Slightly 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

fenoxaprop-P-ethyl

French

fenoxaprop-P-ethyle

German

Fenoxaprop-P

Danish

fenoxaprop-P-ethyl

Italian

fenoxaprop-P-etile

Spanish

fenoxaprop-P-etil

Greek

Polish

fenoksaprop-P etylu

Swedish

fenoxaprop-P-etylester

Hungarian

Dutch

Norwegian

fenoksaprop-P-etyl

Record last updated:	26/08/2024
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