Aclonifen (Ref: AE F068300)

Aclonifen (Ref: AE F068300)	Last updated: 09/04/2025
(Also known as: aclonifene; RPA 099795)

SUMMARY

Aclonifen is a herbicide that is used to control grass and broadleaved weeds. It is not highly soluble in water but is in many organic solvents. It is non-volatile and is not expected to leach to groundwater. It is moderately persistence in soil systems and can be very persistent in aquatic systems under certain conditions. It has a low mammalian toxicity and may bioaccumulate. It is a recognised skin irritant. It is relatively non-toxic to birds and honeybees but more so to most aquatic organisms.

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: Potential for particle bound transport: High	Ecotoxicity High alert: Fish chronic ecotoxicity: High	Human health Moderate alert: Possible Carcinogen; Reproduction/development effects

GENERAL INFORMATION

Description

A nitrophenyl ether herbicide used for the pre-emergence control of grass and broadleaved weeds

Example pests controlled

Buckwheat; Carpetweed; Cocklebur; Lady's thumb; Morning glory; Moonflower; Nighshade; Pigweed; Waterhelp; Foxtails

Example applications

Soybeans; Peanuts; Beans and peas: Rice

Efficacy & activity

Availability status

Current

Introduction & key dates

circa 1983, first introduced

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/07/2025

GB LERAP status

Crop over 5m DRT - See Authorisation for Crop LERAP Details

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Germany

Date EC 1107/2009 inclusion expires

31/10/2026

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
✓		✓	✓	✓	✓	✓	✓	✓

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

Morocco

Chemical structure

Isomerism

None

Chemical formula

C₁₂H₉ClN₂O₃

Canonical SMILES

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

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

DDBMQDADIHOWIC-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C12H9ClN2O3/c13-11-10(18-8-4-2-1-3-5-8)7-6-9(12(11)14)15(16)17/h1-7H,14H2

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Nitrophenyl ether herbicide

Minimum active substance purity

Known relevant impurities

EU dossier - Phenol

Substance origin

Synthetic

Mode of action

Systemic and selective. Bleaching - Carotenoid biosynthesis inhibitor.

CAS RN

74070-46-5

EC number

277-704-1

CIPAC number

498

US EPA chemical code

Not listed

PubChem CID

92389

CLP index number

612-120-00-6

Molecular mass

264.66

PIN (Preferred Identification Name)

2-chloro-6-nitro-3-phenoxyaniline

IUPAC name

2-chloro-6-nitro-3-phenoxyaniline

CAS name

2-chloro-6-nitro-3-phenoxybenzenamine

Other status information

PAN listed Highly Hazardous Chemical

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

Physical state

Yellow powder or crystals

Formulations

Property

Value

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

Example products using this active

Bandur
Mikado
Fenix

Formulation and application details

Usually supplied as a suspension concentrate that 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)

1.4

Low

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

4800

n-Hexane

442000

Toluene

49200

Methanol

730000

Acetone

Melting point (°C)

81.2

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

297

Flashpoint (°C)

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

2.34 X 10⁰⁴

Calculated

Log P

4.37

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.46

Dissociation constant pKa) at 25 °C

-3.15

Very strong acid

Vapour pressure at 20 °C (mPa)

0.016

Low volatility

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

3.03 X 10^-03

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

24 hr

From soil surface

2.4

24 hr

Volatilisation is not considered critical for air pollution

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

Neutral solution: 238nm = 18987, 310nm = 8431, 390nm = 6143

Surface tension (mN m⁻¹)

72.0

20 °C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

117

Persistent

DT₅₀ (lab at 20 °C)

62.3

Moderately persistent

DT₅₀ (field)

80.4

Moderately persistent

DT₉₀ (lab at 20 °C)

364

Persistent

DT₉₀ (field)

316

DT₅₀ modelling endpoint

Note

EU dossier lab studies DT₅₀ range 29.5-93.6 days, DT₉₀ range 107-740 days; field studies DT₅₀ range 13-195 days, DT₉₀ range 104-649 days

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

Note

Aqueous photolysis DT₅₀ (days) at pH 7

Value

197

Stable

Note

Not a major route of degradation. Calculated values range 9-1040 days depending on sunlight levels and temp

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

Value

Stable

Note

Stable between pH 5 and pH 9, 22-70 °C

Water-sediment DT₅₀ (days)

14.3

Fast

Water phase only DT₅₀ (days)

4.2

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)

138.1

Non-mobile

K_foc (mL g⁻¹)

7126

¹/_n

0.922

Notes and range

K_f range 58.5-265.3, K_foc range 5318-10612 mL g⁻¹, ¹/_n range 0.878-1.003, Soils=3

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

0.28

Calculated

Low leachability

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

Value

7.54 X 10^-03

Calculated

Note

Potential for particle bound transport index

High

Calculated

Potential for loss via drain flow

Non-mobile

Calculated

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

30.2

Calculated using the Atkinson method. Assumed 0.5E+06 OH/cm³, 24 hr

Below the level of concern for long-range air transport

Bio-concentration factor

BCF (l kg⁻¹)

2896

Threshold for concern

CT₅₀ (days)

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

3-amino-2-chloro-4-nitrophenol (Ref: RPA 508285)

Minor fraction

3-chloro-4-phenoxybenzene-1,2-diamine (Ref: RPA 407291)

Minor fraction

4-(3-amino-2-chloro-4-nitrophenoxy)phenol (Ref: RPA 407074)

Minor fraction

3,4-diamino-2-chlorophenol (Ref: RPA 407288)

Minor fraction

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

3-amino-2-chloro-4-nitrophenol (Ref: RPA 508285)

Plant

4-(3-amino-2-chloro-4-nitrophenoxy)phenol (Ref: RPA 407074)

Plant

3-chloro-4-phenoxybenzene-1,2-diamine (Ref: RPA 407291)

Plant

3,4-diamino-2-chlorophenol (Ref: RPA 407288)

Plant

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 5000

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

> 50

Rat

High

(ppm diet)

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

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)

> 141

Coturnix japonica NOEL Reproduction

Moderate

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

150

Eisenia foetida corr

Moderate

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

Eisenia andrei corr

Moderate

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect [Dose: 15 kg ha⁻¹, 28 days]
Carbon mineralisation: 8% Effect sand [Dose: 3 kg ha⁻¹, 28 days]
Carbon mineralisation: 22% Effect loam [Dose: 15 kg ha⁻¹, 28 days]

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

13.7

Brassica napus
Vegetative vigour, ER₅₀
as g ha⁻¹

25.7

Brassica napus
Seedling emergence, ER₅₀
as g ha⁻¹

Honeybees (Apis spp.)

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

> 100

Apis mellifera

Low

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

> 107

Apis mellifera

Low

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

Chronic

Notes

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)

Beneficial insects (Lacewings)

3.7% Mortality at dose 721 g ha⁻¹

Chrysoperla carnea Larva

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

> 2930

Aphidius rhopalosiphi

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

102

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)

0.67

Oncorhynchus mykiss

Moderate

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

0.005

Pimephales promelas

High

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

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

1.2

Daphnia magna

Moderate

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

0.016

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)

0.472

Chironomus riparius

Moderate

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

32.0

Chironomus riparius

Moderate

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

0.006

Lemna gibba

High

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

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

0.47

Navicula pelliculosa

Moderate

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)

> 5000

Rat

Low

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

5000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

5.06

Rat 4 hr (nose only)

Other Mammal toxicity endpoints

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

0.07

Rat SF=100

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

None allocated

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

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

0.07

Rat SF=100

Dermal penetration studies (%)

2-10

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

Risk of exposure to bystanders from spray drift, but acceptable risk level for proposed used
Very low risk of exposure via diet

Occupational

Main risk from dermal absorption during preparation and mixing
Acceptable risk level for proposed uses

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

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

Possible kidney toxicant
CLP data - suspected carcinogen

Handling issues

Property

Value and interpretation

General

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

CLP classification 2013

Health: H317, H351
Environment: H400, H410

WHO Classification

U (Unlikely to present an acute hazard)

UN Number

UN3077

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

aclonifen

French

aclonifene

German

Aclonifen

Danish

aclonifen

Italian

aclonifen

Spanish

aclonifen

Greek

Polish

aklonifen

Swedish

aklonifen

Hungarian

Dutch

aclonifen

Norwegian

aklonifen

Record last updated:	09/04/2025
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