Acifluorfen (Ref: RH 5781)

Acifluorfen (Ref: RH 5781)	Last updated: 13/01/2023
(Also known as: acifluorofen; acifluorfen metabolite; lactofen metabolite; PPG 847; carbofluorfen)

SUMMARY

Acifluorfen is a post-emergence herbicide, usually used as the sodium salt. It is highly soluble in water, with a low vapour pressure and may be moderately persistent in soils and water depending upon conditions. Based on its chemical properties it has a high potential for leaching to groundwater. It has a low to moderate toxicity to most biodiversity. It is not highly toxic to human but is known to be a skin and eye 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 High alert: GUS: High leachability Warning: Significant data are missing	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate	Human health Moderate alert: Mammals acute toxicity: Moderate; Possible Carcinogen; Possible Reproduction/development effects

GENERAL INFORMATION

Description

Post emergence herbicide, usually used as the sodium salt; particularly effective against broad-leaved weeds and grasses. Also a pesticide transformation product.

Example pests controlled

Carpetweed; Balloonvine; Wild buckwheat; Cocklebur; Ladysthumb; Lambsquarters; Copperleaf; Morning glory; Moonflower; Nightshade; Pigweed; Foxtails

Example applications

Soybean; Peanuts; Rice

Efficacy & activity

Availability status

Current

Introduction & key dates

1980, USA

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Expired

UK LERAP status

No UK approval for use

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

Not applicable

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

Additional information

Also used in

Chemical structure

Isomerism

None

Chemical formula

C₁₄H₇ClF₃NO₅

Canonical SMILES

C1=CC(=C(C=C1C(F)(F)F)Cl)OC2=CC(=C(C=C2)[N+](=O)[O-])C(=O)O

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

NUFNQYOELLVIPL-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C14H7ClF3NO5/c15-10-5-7(14(16,17)18)1-4-12(10)24-8-2-3-11(19(22)23)9(6-8)13(20)21/h1-6H,(H,20,21)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
acifluorfen	-

General status

Pesticide type

Herbicide, Metabolite

Metabolite Type

Soil

Substance groups

Nitrophenyl ether herbicide

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Contact action. Inhibition of protoporphyrinogen oxidase (PPO).

CAS RN

50594-66-6

EC number

256-634-5

CIPAC number

497

US EPA chemical code

114401

PubChem CID

44073

CLP index number

604-041-00-0

Molecular mass

361.66

PIN (Preferred Identification Name)

5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid

IUPAC name

5-(2-chloro-α,α,α-trifluoro-p-tolyloxy)-2-nitrobenzoic acid

CAS name

5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid

Other status information

Chemical subject to PIC regulations; Potential groundwater pollutant; PAN Bad Actor

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

Off-white coloured solid

Related substances & organisms

acifluorfen-methyl

acifluorfen-sodium

fluoroglycofen

lactofen

Can be a metabolite of:

Parent

Formation medium

Estimated maximum occurrence fraction

1107/2009 relevancy

acifluorfen-sodium

Soil

Major fraction

fluoroglycofen

Soil

lactofen

Soil

acifluorfen-methyl

Soil

Major fraction

Formulations

Property

Value

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

Rohm and Haas
United Phosphorus

Example products using this active

Blazer
Tackle

Formulation and application details

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

250000

High

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

50000

Acetone

1000

n-Hexane

Melting point (°C)

155

Boiling point (°C)

Degradation point (°C)

235

Flashpoint (°C)

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

1.51 X 10⁰¹

Calculated

Log P

1.18

Low

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

3.86

Weak acid

Vapour pressure at 20 °C (mPa)

0.133

Low volatility

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

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)

Moderately persistent

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Other sources: DT₅₀ 108 (silt loam) - 200 (clay) days (R3)

Dissipation rate RL₅₀ on plant matrix

Value

Note

Dissipation rate RL₅₀ on and in plant matrix

Value

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Moderately fast

Note

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

Value

Stable

Note

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

Moderately mobile

K_oc

113

Notes and range

Freundlich

K_f

13.2

Moderately mobile

K_foc

160

¹/_n

1.05

Notes and range

Literature data: K_f range 0.57-43.11 mL g⁻¹, K_foc range 65.3-291.3 mL.g, ¹/_n range 0.952-1.190, Soils=5

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

3.11

Calculated

High leachability

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

Value

3.53 X 10^-01

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

Bio-concentration factor

BCF (l kg⁻¹)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

1370

Rat

Moderate

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)

2821

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

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

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

> 1800

Eisenia foetida as sodium salt

Low

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)

> 100

Low

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)

Chronic

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

Beneficial insects (Ladybirds)

Beneficial insects (Lacewings)

Beneficial insects (Parasitic wasps)

Beneficial insects (Predatory mites)

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Oncorhynchus mykiss

Moderate

Fish - Chronic 21 day NOEC (mg l⁻¹)

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

Daphnia magna

Moderate

Aquatic invertebrates - Chronic 21 day NOEC (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 - Acute 7 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

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)

1370

Rat

Moderate

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

2000

Rabbit

Mammals - Inhalation LC₅₀ (mg l⁻¹)

6.9

Rat 4 hr

Other Mammal toxicity endpoints

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

0.0125

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

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

Exposure Routes

Public

Occupational

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

No data found

General human health issues

Slightly toxic
Liver, heart, and kidney toxicant at high doses

Handling issues

Property

Value and interpretation

General

Not expected to autoignite; Not highly flammable

CLP classification 2013

Health: H302, H315, H318
Environment: H400, H410

WHO Classification

II (Moderately hazardous)

UN Number

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

acifluorfen

French

German

Danish

acifluorfen

Italian

Spanish

acifluorfen

Greek

Polish

acifluorfen

Swedish

Hungarian

acifluorfen

Dutch

Record last updated:	13/01/2023
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