Oxyfluorfen (Ref: RH 2915)

Oxyfluorfen (Ref: RH 2915)	Last updated: 12/01/2021
(Also known as: oxyfluorofene; oxyfluorfen)

GENERAL INFORMATION

Description

A broad-spectrum, pre- and post-emergent herbicide used to control certain annual weeds in vegetables, fruit and other crops

Example pests controlled

Annual broad-leaved; Grassy weeds

Example applications

Sugarcane; Vegetables including alliums, peas, cabbage; Fruit; Nuts including almonds; Cotton; Ornamentals; non-crop areas including landscapes, residential and amenity sites

Efficacy & activity

Availability status

Current

Introduction & key dates

1975, first reported; 1976, first marketed

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Not applicable

UK LERAP status

No UK approval for use

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Spain/Hungary

Date EC 1107/2009 inclusion expires

31/12/2021

EU Candidate for substitution (CfS)

Yes - two 'Persistent-Bioaccumulative-Toxic' criteria

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
	✓		✓	✓	✓

Also used in

Australia, USA

Chemical structure

Isomerism

Chemical formula

C₁₅H₁₁ClF₃NO₄

Canonical SMILES

CCOC1=C(C=CC(=C1)OC2=C(C=C(C=C2)C(F)(F)F)Cl)[N+](=O)[O-]

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

OQMBBFQZGJFLBU-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C15H11ClF3NO4/c1-2-23-14-8-10(4-5-12(14)20(21)22)24-13-6-3-9(7-11(13)16)15(17,18)19/h3-8H,2H2,1H3

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
oxyfluorfen	-

General status

Pesticide type

Herbicide

Substance group

Diphenyl ether

Minimum active substance purity

970 g kg⁻¹

Known relevant impurities

EU dossier - N,N-domethylnitrosamine 0.01g kg⁻¹

Substance origin

Synthetic

Mode of action

Selective with contact action. Inhibits protoporphyrinogen oxidase, leading to irreversible cell membrane damage.

CAS RN

42874-03-3

EC number

255-983-0

CIPAC number

538

US EPA chemical code

111601

PubChem CID

39327

Molecular mass

361.7

PIN (Preferred Identification Name)

IUPAC name

2-chloro-α,α,α-trifluoro-p-tolyl 3-ethoxy-4-nitrophenyl ether

CAS name

2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene

Other status information

Relevant Environmental Water Quality Standards

Herbicide Resistance Classification (HRAC)

Herbicide Resistance Classification (WSSA)

Insecticide Resistance Classification (IRAC)

Not applicable

Fungicide Resistance Classification (FRAC)

Not applicable

Examples of recorded resistance

Physical state

Orange to brown crystalline powder

Related substances & organisms

propylene glycol

Formulations

Property

Value

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

Goal
Scualo 24 EC
Koltar

Example products using this active

Dow AgroSciences
Cequisa SA SPAIN
Makhteshim-Agan
Rohm & Haas

Formulation and application details

Usually supplied as granules or an emulsifiable concentrate

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

0.116

Low

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

134000

Acetone

3800

n-Heptane

30000

Methanol

132000

Ethyl acetate

Melting point (°C)

85.3

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

331

Flashpoint (°C)

Not expected to self ignite; Not highly flammable

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

7.24 X 10⁰⁴

Calculated

Log P

4.86

High

Bulk density (g ml⁻¹)

1.53

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.026

Low volatility

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

0.02382

Non-volatile

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

Neutral solution: 275nm = 6135, 320nm = 4730
Acidic solution: 273nm = 6276, 320nm = 4730
Basic solution: 273nm = 6445, 320nm = 4828

Surface tension (mN m⁻¹)

72.19

at 19°C

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)

138

Persistent

DT₅₀ (field)

Moderately persistent

DT₉₀ (lab at 20 °C)

663

Very persistent

DT₉₀ (field)

417

DT₅₀ modelling endpoint

Note

EU dossier Lab studies DT₅₀ range 62-438 days; DT₉₀ range 231-1771 days, Field data DT₅₀ range 31-172 days, DT₉₀ range 274-571 days; Other literature data DT₅₀ 30-60 days

Dissipation rate RL₅₀ on plant matrix

Value

1.6

Note

Onion leaves, n=1

Dissipation rate RL₅₀ on and in plant matrix

Value

3.6

Note

Published literature RL₅₀ range 1.0-6.0 days, 2 field crops, various matrices, n=2

Aqueous photolysis DT₅₀ (days) at pH 7

Value

5.6

Moderately fast

Note

DT₅₀: 4.3 days at 30 deg N, 5.6 days 40 deg N, 8.9 days 50 deg N, 20.5 days 60 deg N, mean seasonal value

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

Value

Stable

Note

Stable pH 5 to pH 9

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

K_oc

Notes and range

Freundlich

K_f

99.37

Non-mobile

K_foc

7566

¹/_n

0.92

Notes and range

EU dossier K_f range 8.5-228.6, K_foc range 2891-13711 mL g⁻¹, ¹/_n range 0.787-1.076

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

0.23

Calculated

Low leachability

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

Value

6.99 X 10^-03

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Non-mobile

Calculated

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

Metabolising enzymes

Ref: RH-123394
Note: Minor metabolite

Water (Photolysis)

Ref: RH-45298C

Rat (Urinary)

Ref: RH-31689

Soil (Photolysis)

Ref: RH-36329

Soil (Photolysis)

Ref: RH-45451

Rat (Faeces)

Ref: RH-120832

Rat (Faeces)

Ref: RH-120450

Rat (Faeces)

Ref: RH-120162

Rat (Faeces)

3-Chloro-4-hydroxy benzoic acid (Ref: RH-31680)

Unknown

Ref: RH-35451
Note: Minor metabolite

Water (Photolysis)

Ref: RH-34670

hydro-oxyfluorfen

Rat (Faeces); Water (Photolysis)

4-trifluoromethyl-2-chlorophenol (Ref: RH-34800)

Rat (Urinary); Water (Photolysis); Soil (Photolysis)

Ref: RH-45298-C

Rat (Urinary)

Ref: RH-45469
Note: Minor metabolite

Water (Photolysis); Rat (Faeces)

ECOTOXICOLOGY

Property

Value

Source; quality score; and other information

Interpretation

Bio-concentration factor

BCF (l kg⁻¹)

1637

Threshold for concern

CT₅₀ (days)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 5000

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

Rat

(ppm diet)

> 200

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

Birds - Acute LD₅₀ (mg kg⁻¹)

> 947

Colinus virginianus

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

> 462 mg kg bw⁻¹ day⁻¹

Colinus virginianus

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

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

0.25

Oncorhynchus mykiss

Moderate

Fish - Chronic 21 day NOEC (mg l⁻¹)

0.038

Pimephales promelas

Moderate

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

0.072

Daphnia magna

High

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

0.013

Daphnia magna

Moderate

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)

0.08

Chironomus riparius

Moderate

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

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

0.0014

Lemna gibba

High

Non-target plants

14.6

Pomes Vines
Vegetative vigour, ER₅₀
as g ha⁻¹

13.4

Pomes Vines
Seedling emergence, ER₅₀
as g ha⁻¹

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

> 2.0

Pseudokirchneriella subcapitata

Moderate

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

2.0

Pseudokirchneriella subcapitata

Low

Honeybees (Apis spp.)

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

> 100

Low

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

> 100

Low

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

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 pollinators (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other pollinators (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

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

> 1000

Eisenia foetida

Low

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

24.09

Eisenia foetida

Moderate

Other soil macro-organisms

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

0.125

Folsomia candida 28d

Other arthropod (1)

LR₅₀ g ha⁻¹

1440

>
Typhlodromus pyri protonymphs

% Effect

Other arthropod (2)

LR₅₀ g ha⁻¹

1440

>
Pardosa spp.

% Effect

Soil micro-organisms

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

Dose: 1.44 kg ha⁻¹

Mesocosm study data

NOEAEC 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)

> 5000

Rat

Low

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

5000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 3.71

Rat (nose only aerosol)

Other Mammal toxicity endpoints

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

0.003

Rat SF=100

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

0.30

Rabbit 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)

0.013

Dog SF=100

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders identified

Occupational

Acceptable risk to operator for intended uses
Risks identified for workers re-entering sprayed ruit/wine areas - clsoed re-entry periods must be imposed

European MRLs

EU MRL pesticide database

Drinking Water Standards

Drinking Water MAC (μg l⁻¹)

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Liver and spleen toxicant
USEPA - probable human carcinogen

Handling issues

Property

Value and interpretation

General

Not explosive
IMDG Transport Code is usually 3

CLP classification 2013

Health: H315, H319, H332, H335, H351
Environment: H400, H410

EC Risk Classification

Carcinogen category 3: R40
N - Dangerous for the environment: R50, R53

EC Safety Classification

S1/2

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

Usually 1145

Waste disposal & packaging

Packaging Group II (medium danger)

TRANSLATIONS

Language

Name

English

oxyfluorfen

French

oxyfluorfene

German

Oxyfluorfen

Danish

oxyfluorfen

Italian

oxifluorfen

Spanish

oxifluorfen

Greek

Polish

oksyfluorfen

Swedish

Hungarian

oxifluorfen

Dutch

Record last updated:	12/01/2021
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