Phenmedipham (Ref: SN 38584)

Phenmedipham (Ref: SN 38584)	Last updated: 22/08/2024
(Also known as: fenmedifam ; phenmediphame; EP 452; betanal)

SUMMARY

Phenmedipham is a carbamate herbicide used for the control of broad-leaved weeds. It has a low aqueous solubility, a low volatility and is not generally expected to leach to groundwaters. It is not normally persistent in soil or water systems. It has a low mammalian toxicity but has been associated with the development of some cancers. Phenmedipham is moderately toxic to most aquatic and terrestrial fauna and flora.

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: Drainflow: Slightly mobile; Potential for particle bound transport: Medium	Ecotoxicity Moderate alert: Birds chronic ecotoxicity: Moderate; Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate; Earthworms chronic ecotoxicity: Moderate	Human health Moderate alert: Possible Carcinogen; Reproduction/development effects

GENERAL INFORMATION

Description

A herbicide used to control most broad-leaved weeds in their early growth stages

Example pests controlled

Kochia; Lambsquarters; Mustard; Foxtail; Shepherds purse; Chickweed; Goosefoot; Ragweed

Example applications

Sugar beet; Fodder beet; Red beet; Mangels; Spinach; Swiss chard; Strawberries

Efficacy & activity

Shown to control a wide range of broad-leaved weeds in numerous field trials.

Availability status

Current

Introduction & key dates

1967, first reported

UK regulatory status

UK COPR regulatory status

Approved

Date COPR inclusion expires

31/07/2029

UK LERAP status

Cat B

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Finland/Denmark

Date EC 1107/2009 inclusion expires

15/02/2025

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

Chemical structure

Isomerism

None

Chemical formula

C₁₆H₁₆N₂O₄

Canonical SMILES

CC1=CC(=CC=C1)NC(=O)OC2=CC=CC(=C2)NC(=O)OC

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

IDOWTHOLJBTAFI-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C16H16N2O4/c1-11-5-3-6-12(9-11)18-16(20)22-14-8-4-7-13(10-14)17-15(19)21-2/h3-10H,1-2H3,(H,17,19)(H,18,20)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
phenmedipham	-

General status

Pesticide type

Herbicide

Substance groups

Carbanilate herbicide

Minimum active substance purity

970 g kg⁻¹

Known relevant impurities

EU dossier - toluene, 3-methylaniline, 3-aminophenol

Substance origin

Synthetic

Mode of action

Inhibits photosynthesis (photosystem II) and acts by disrupting carbon dioxide. It is a contact herbicide which is absorbed through the leaves with translocation primarily in the apoplast.

CAS RN

13684-63-4

EC number

237-199-0

CIPAC number

US EPA chemical code

098701

PubChem CID

24744

CLP index number

616-106-00-0

Molecular mass

300.31

PIN (Preferred Identification Name)

IUPAC name

methyl 3-(3-methylcarbaniloyloxy)carbanilate

CAS name

3-[(methoxycarbonyl)amino]phenyl (3-methylphenyl)carbamate

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

Physical state

Colourless crystalline powder

Formulations

Property

Value

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

AgriGuard
Bayer CropScience
Landgold
Makhteshim-Agan
Nufarm UK

Example products using this active

Betana Carrera
Betana Expert
Betanal Flow
PowerTwin
Pump
Twin
Kemipham
Morton
Spinaid

Formulation and application details

Often supplied as a soluble or emulsifiable concentrate or liquid concentrate

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

1.8

at pH 3.4

Low

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

970

Toluene

36800

Methanol

193000

Acetone

65000

Ethyl acetate

Melting point (°C)

148.3

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

240

Flashpoint (°C)

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

5.01 X 10⁰²

Calculated

Log P

2.7

Moderate

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.36

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

7.00 X 10^-07

Low volatility

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

2.7 X 10^-08

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Neutral soln: 205nm = 59646, 237nm = 37848, 274nm = 2761

Surface tension (mN m⁻¹)

70.5

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Non-persistent

DT₅₀ (lab at 20 °C)

Non-persistent

DT₅₀ (field)

16.7

Non-persistent

DT₉₀ (lab at 20 °C)

118.8

Persistent

DT₉₀ (field)

74.3

DT₅₀ modelling endpoint

95.5

Note

EU 2016 dossier lab studies DT₅₀ range 4.2-139.8 days, DT₉₀ range13.4-317.3 days, Soils=12; Field studies DT₅₀ range 5.8-39.9 days, DT₉₀ range 30-132.6 days, Soils=5

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

Stable

Note

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

Value

0.5

Non-persistent

Note

pH sensitive: DT₅₀ 259 days at pH 4, 47 days at pH 5, 12 hours at pH 7, 7 minutes at pH 9, all at 25 °C

Water-sediment DT₅₀ (days)

0.12

Fast

Water phase only DT₅₀ (days)

0.2

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)

35.2

Slightly mobile

K_oc (mL g⁻¹)

1775

Notes and range

EU 2016 dossier K_d range 11.9-64.3 mL g⁻¹, koc range 1631-2015 mL g⁻¹, Soils = 3; Other sources: 2400 mL g⁻¹ (DW3)

Freundlich

K_f (mL g⁻¹)

20.22

Slightly mobile

K_foc (mL g⁻¹)

1142

¹/_n

0.81

Notes and range

EU 2016 dossier K_f range 4.5-42.1 mL g⁻¹, K_foc range 657-1618 mL.g, ¹/_n range 0.77-0.87, Soils =10

pH sensitivity

Yes, due to the hydrolysis processes which indirectly affects the adsorption.

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.15

Calculated

Low leachability

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

Value

2.10 X 10^-02

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Slightly mobile

Calculated

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

0.82

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)

165

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

m-toluidine

Major fraction

0.186

Bayer verified

methyl-3-hydroxylphenylcarbamate

Major fraction

0.140

Bayer verified

3-aminophenol

Minor fraction

0.04

3-aminotoluene

Known groundwater metabolites

Metabolite

EC SANCO/221/2000 relevancy

ADI (mg kg⁻¹ bodyweight day⁻¹)

WHO drinking water guidance value (μg L⁻¹ day⁻¹)

methyl-3-hydroxylphenylcarbamate

Not relevant

m-toluidine

Not relevant

Other known metabolites

None

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)

Rat 2 yr

(ppm diet)

> 100

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

225

Unknown species Reproductive NOAEL

Low

Birds - Acute LD₅₀ (mg kg⁻¹)

> 2500

Anas platyrhynchos

Low

Birds - Short term dietary (LC₅₀/LD₅₀)

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

121

Colinus virginianus NOAEL

Moderate

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

Eisenia foetida corr

Moderate

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

>= 10

Eisenia foetida corr

Moderate

Soil micro-organisms

Nitrogen mineralisation: No significant adverse effect [Dose: 13 mg kg⁻¹ soil]
Carbon mineralisation: Slight reversable effects [Dose: 1 kg ha⁻¹]

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

>= 500

Folsomia candida corr

Non-target plants

> 2.0

Onion Lettuce
Seedling emergence, ER₅₀
as g ha⁻¹

2.7

Tomato
Vegetative vigour, 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)

> 104.8

Apis mellifera

Low

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

Chronic as 10-day LDD₅₀ mg kg⁻¹

> 4.6

Apis mellifera

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)

> 100

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 g ha⁻¹

> 960

Chrysoperla carnea

Beneficial insects (Parasitic wasps) as Mortlity LR₅₀ g ha⁻¹

293.9

Aphidius rhopalosiphi

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

> 960

Typhlodromus pyri

Beneficial insects (Ground beetles) as Mortality LR₅₀ g ha⁻¹

> 960

Poecilus cupreus

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

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

1.84

Oncorhynchus mykiss

Moderate

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

0.041

Oncorhynchus mykiss

Moderate

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

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

2.033

Daphnia magna

Moderate

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

0.061

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)

>= 6.86

Chironomus riparius

Moderate

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

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

> 0.157

Lemna minor

Moderate

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

0.086

Raphidocelis subcapitata

Moderate

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)

> 5000

Rat

Low

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

2500

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 7.0

Rat 4 hr (nose only)

Other Mammal toxicity endpoints

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

0.03

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)

0.13

Rat 90 day SF=100

Dermal penetration studies (%)

0.2-1.0

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

No unacceptable risks to bystanders or residents identified

Occupational

No unacceptable risks to operators or other workers identified but PPE/PPC recommended

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

Rapid and extensive excretion via both urine and faeces

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

General human health issues

Moderately toxic
May cause dermatitis
Possible blood, spleen, liver & kidney toxicant
Some weak evidence suggests carcinogenicity

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

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

phenmedipham

French

phenmediphame

German

Phenmedipham

Danish

phenmedipham

Italian

fenmedifam

Spanish

fenmedifam

Greek

Polish

fenmedifam

Swedish

fenmedifam

Hungarian

fenmedifam

Dutch

fenmedifam

Norwegian

fenmedifam

Record last updated:	22/08/2024
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