Napropamide-M

Napropamide-M	Last updated: 28/02/2025
(Not known by any other names)

SUMMARY

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: Moderately persistent; GUS: Transition state; Drainflow: Slightly mobile	Ecotoxicity Moderate alert: 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: Reproduction/development effects

GENERAL INFORMATION

Description

A soil applied herbicide for pre-emergence control of weeds in a range of crops including oilseed rape, fruit and woody ornamentals

Example pests controlled

Annual grasses; Broadleaved weeds

Example applications

Vegetables including brassicas, Fruit tree and bushes; Vines; Tobacco; Olives; Sunflowers; Turf; Oilseed rape; Ornamentals

Efficacy & activity

Efficiacy demonstrated during reported field trials

Availability status

Current

Introduction & key dates

circa 1970, introduced as generic isomer mix

GB regulatory status

GB COPR regulatory status

Pending

Date COPR inclusion expires

GB LERAP status

No UK approval for use as a plant protection agent

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Pending

Dossier rapporteur/co-rapporteur

Slovenia

Date EC 1107/2009 inclusion expires

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

Chemical structure

Isomerism

Napropamide is a chiral molecule that exists in the R- and S-forms. Napropamide-M is the biologically active R-isomer.

Chemical formula

C₁₇H₂₁NO₂

Canonical SMILES

CCN(CC)C(=O)C(C)OC1=CC=CC2=CC=CC=C21

Isomeric SMILES

CCN(CC)C(=O)[C@@H](C)OC1=CC=CC2=CC=CC=C21

International Chemical Identifier key (InChIKey)

WXZVAROIGSFCFJ-CYBMUJFWSA-N

International Chemical Identifier (InChI)

InChI=1S/C17H21NO2/c1-4-18(5-2)17(19)13(3)20-16-12-8-10-14-9-6-7-11-15(14)16/h6-13H,4-5H2,1-3H3/t13-/m1/s1

2D structure diagram/image available?

Yes

General status

Pesticide type

Herbicide

Substance groups

Amide herbicide

Minimum active substance purity

930 g/Kg

Known relevant impurities

EU 2017 dossier: None declared

Substance origin

Synthetic

Mode of action

Selective, systemic, absorbed through roots and translocated. Acts by preventing root cell elongation and so disrupting growth. Inhibition of very long chain fatty acids (VLCFA, inhibition of cell division)

CAS RN

41643-35-0

EC number

No data found

CIPAC number

271

US EPA chemical code

PubChem CID

13013865

CLP index number

No data found

Molecular mass

271.36

PIN (Preferred Identification Name)

(2R)-N,N-diethyl-2-(naphthalen-1-yloxy)propanamide

IUPAC name

(R)-N,N-diethyl-2-(1-naphthyloxy)propionamide

CAS name

(2R)-N,N-diethyl-2-(1-naphthalenyloxy)propanamide

Other status information

Potential groundwater contaminant

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 crystals to light brown solid depending on purity

Related substances & organisms

napropamide

Formulations

Property

Value

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

United Phosphorus

Example products using this active

Formulation and application details

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

for isomeric mix

Moderate

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

10000

n-Heptane

250000

1,2-Dichlorormethane

250000

Methanol

25000

Acetone

Melting point (°C)

92.2

for isomeric mix

Boiling point (°C)

319.4

for isomeric mix

Degradation point (°C)

Flashpoint (°C)

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

1.86 X 10⁰³

Calculated

Log P

3.27

for isomeric mix

High

Fat solubility of residues

Solubility

Soluble

Data type

Regulatory data

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

3.20 X 10^-03

for isomeric mix at 25 °C

Low volatility

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

2.644 X 10^-05

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Acidic soln: 217nm=48138, 289nm=4987
Neutral soln: 217nm=52385, 290nm=5579
basic soln: 217nm=13123, 291nm=2271

Surface tension (mN m⁻¹)

56.9

20 °C

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

608

Very persistent

DT₅₀ (lab at 20 °C)

608

Very persistent

DT₅₀ (field)

32.2

Moderately persistent

DT₉₀ (lab at 20 °C)

2646

Very persistent

DT₉₀ (field)

336.4

DT₅₀ modelling endpoint

Note

EU 2017 dossier DT₅₀ range 382-1150 days, DT₉₀ range 1270-5250 days, Soils=5; Field studies DT₅₀ range 5.31-101 days, DT₉₀ range 135-900 days, Soils=8

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

0.01

Fast

Note

Very rapid

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

Value

Stable

Note

Stable at all relevant pH values

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

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)

11.25

Slightly mobile

K_oc (mL g⁻¹)

831.6

Notes and range

EU 2017 dossier K_d range 5.46-21.47 mL g⁻¹, K_oc range 496.45-1285.4 mL g⁻¹, Soils=5

Freundlich

K_f (mL g⁻¹)

6.48

Moderately mobile

K_foc (mL g⁻¹)

496.6

¹/_n

0.87

Notes and range

EU 2017 dossier K_f range 3.31-10.57 mL g⁻¹, K_foc range 313.1-746.7 mL g⁻¹, ¹/_n range 0.843-0.917, Soils=5

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.97

Calculated

Transition state

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

Value

7.03 X 10^-02

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Slightly mobile

Calculated

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

0.552

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)

Low potential

CT₅₀ (days)

No data

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 2000

Rat

Low

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)

> 2000

Coturnix japonica

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)

122.02

Eisenia foetida

Moderate

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

41.7

Eisenia foetida

Moderate

Soil micro-organisms

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

Dose: 79.12 mg kg⁻¹ soil 28 Day

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

47.0

Folsomia candida

Non-target plants

1408

Zea mays
Vegetative vigour, ER₅₀
as g ha⁻¹

321

Zea mays
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)

> 110

Apis mellifera

Low

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

> 110

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)

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

> 4140

Aphidius rhopalosiphi,/i>

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

> 4140

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)

11.2

Oncorhynchus mykiss as D-napropamide

Moderate

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

> 0.4

Danio rerio early life 30 day

Moderate

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

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

Daphnia magna as isomeric mix

Moderate

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

0.3

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)

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

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

0.08

Lemna gibba

Moderate

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

> 2.35

Myriophyllum spicatum 7d

Moderate

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

28.18

Pseudokirchneriella subcapitata

Low

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)

> 2000

Rat

Low

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

2000

rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 4.8

Rat 4 hr (nose only)

Other Mammal toxicity endpoints

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

0.3

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)

None allocated

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

0.5

Dog SF=100

Dermal penetration studies (%)

0.6-18

concentration dependent

Dangerous Substances Directive 76/464

Exposure Routes

Public

negligible risks levels for bystanders

Occupational

PPE/PPC recommended for operators

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 elimination within 72hr via both urine and faeces

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

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 liver 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

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

napropamide-M

French

napropamide-M

German

Napropamid-M

Danish

napropamid-M

Italian

napropamide-M

Spanish

napropamida-M

Greek

Polish

napropamid-M

Swedish

napropamid-M

Hungarian

napropamid-M

Dutch

Norwegian

Record last updated:	28/02/2025
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