Asulam (Ref: M&B 9057)

Asulam (Ref: M&B 9057)	Last updated: 22/08/2024
(Also known as: MB 9057)

SUMMARY

Asulam is a carbamate herbicide. It is highly soluble in water, relatively volatile with a low risk of leaching to groundwater. It is not persistent in soils but may be persistent in water especially under dark conditions. Although it is not highly toxic there is a risk of bioaccumulation. It is a skin, eye and respiratory system irritant and may cause undesirable effects on reproduction. It is moderately toxic to birds, most aquatic organisms, honeybees and earthworms.

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: Drainflow: Mobile	Ecotoxicity Moderate alert: Birds acute ecotoxicity: Moderate; Birds chronic ecotoxicity: Moderate; Fish acute ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate	Human health High alert: Reproduction/development effects Warning: Significant data are missing

GENERAL INFORMATION

Description

A translocated carbamate herbicide for control of stubborn weeds which is usually used as the sodium or potassium salt.

Example pests controlled

Docks; Bracken

Example applications

Fruit including apples, pears, plums, cherries, blackcurrants; Hops; Grazing land; Amenity grassland; Moorland

Efficacy & activity

Availability status

Current

Introduction & key dates

1965, introduced

GB regulatory status

GB COPR regulatory status

Not approved

Date COPR inclusion expires

Expired

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

Not approved

Dossier rapporteur/co-rapporteur

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

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

None

Chemical formula

C₈H₁₀N₂O₄S

Canonical SMILES

COC(=O)NS(=O)(=O)C1=CC=C(C=C1)N

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

VGPYEHKOIGNJKV-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C8H10N2O4S/c1-14-8(11)10-15(12,13)7-4-2-6(9)3-5-7/h2-5H,9H2,1H3,(H,10,11)

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
asulam	-

General status

Pesticide type

Herbicide

Substance groups

Carbamate herbicide; Sulphonamide herbicide

Minimum active substance purity

>800 g kg⁻¹

Known relevant impurities

EU dossier - Methanol

Substance origin

Synthetic

Mode of action

Selective system action, absorbed by leaves, shoots and roots. Inhibition of dihydropterate synthase causing slow chlorosis.

CAS RN

3337-71-1

EC number

222-077-1

CIPAC number

240

US EPA chemical code

106901

PubChem CID

18752

CLP index number

No data found

Molecular mass

230.24

PIN (Preferred Identification Name)

methyl (4-aminobenzenesulfonyl)carbamate

IUPAC name

methyl sulfanilylcarbamate

CAS name

methyl [(4-aminophenyl)sulfonyl]carbamate

Other status information

Chemical subject to PIC regulations. Emergency approval for bracken control is sometimes given.

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

Related substances & organisms

asulam sodium

Formulations

Property

Value

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

Bayer CropScience
Dow AgroSciences
AgriGuard
GreenCrop
May & Baker

Example products using this active

Asulox F
Asulox 40
Jonnix
Formule 1

Formulation and application details

Usually formulated as the sodium salt.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

962000

High

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

1100

Acetone at 25 °C

98.0

Xylene

500

Ethyl acetate

300

n-Octanol

Melting point (°C)

230

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

230

Flashpoint (°C)

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

1.41 X 10⁰⁰

Calculated

Log P

0.15

at 25 °C

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

1.29

pKa(2) = 4.68

Vapour pressure at 20 °C (mPa)

5.0 X 10^-04

at 45 °C

Low volatility

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

1.31 X 10^-10

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

203nm = 221771, 293nm = 27501

Surface tension (mN m⁻¹)

71.5

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

3.2

Non-persistent

DT₅₀ (lab at 20 °C)

3.2

Non-persistent

DT₅₀ (field)

Non-persistent

DT₉₀ (lab at 20 °C)

15.1

Non-persistent

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

EU Dossier DT₅₀ range 2.1-4.2 days, DT₉₀ range 7.0-30.9 days; General literature states DT₅₀ 6-14 days; Other literature DT₅₀ range 9-39 days (R3)

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

Note

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

Value

Stable

Note

Degradation very slow

Water-sediment DT₅₀ (days)

71.9

Moderately fast

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)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

0.8

Mobile

K_foc (mL g⁻¹)

¹/_n

0.75

Notes and range

EU dossier K_f range 0.1-2.6, K_foc range 15.4-149.7 mL g⁻¹, ¹/_n range 0.68-0.82, Soils=6

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

2.58

Calculated

Transition state

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

Value

4.62 X 10^-02

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Mobile

Calculated

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

Bio-concentration factor

BCF (l kg⁻¹)

Low risk

Based on LogP < 3

Low risk

CT₅₀ (days)

No data

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

sulphanilamide

Major fraction

acetyl-asulam

Minor fraction

acetylsulphanilamide

Minor fraction

aminobenzenesulphonic acid

Minor fraction

N-(4-aminophenyl)formamide

Minor fraction

methyl phenylsulphonylcarbamate

Minor fraction

benzenesulphonamide

Minor fraction

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

asulam glucosides

Plant

methyl phenylsulphonylcarbamate

desamino asulam; MBSC

Plant

4-acetylbenzenesulphonamide

Plant

formyl asulam

Plant

aminobenzenesulphonic acid

Surface water

N-(4-aminophenyl)formamide

Water

malonyl-asulam

Plant

malonyl-sulphanilamide

Processing

acetylsulphanilamide

Animal (Urine)

acetyl-asulam

Animal (Urine); Plant

sulphanilamide

Animal

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)

(ppm diet)

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

Rat Reproductive NOAEL

Moderate

Birds - Acute LD₅₀ (mg kg⁻¹)

> 1827

Colinus virginianus

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

> 100000 mg kg feed⁻¹

Anas platyrhynchos

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

Coturnix japonica NOAEL

Moderate

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

1000

Eisenia foetida

Moderate

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

Soil micro-organisms

Nitrogen mineralisation: -26% effect
Carbon mineralisation: No significant adverse effect

Dose: 160 mg kg⁻¹ soil

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

Apis mellifera

Low

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

> 123.7

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

3.09

Aphidius rhopalosiphi

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

7.57

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)

> 91.3

Lepomis macrochirus

Moderate

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

> 119.1

Oncorhynchus mykiss

Low

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

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

> 57.9

Daphnia magna

Moderate

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

6.4

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)

100.0

Chironomus riparius

Low

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

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

0.27

Lemna gibba

Moderate

Aquatic plants (rooted, growth) - Acute 14 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

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)

2000

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

> 5.46

Rat 4 hr (whole body)

Other Mammal toxicity endpoints

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

0.36

as sodium variant

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

1.0

as sodium variant

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

Not applicable

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

0.46

as sodium variant

Dermal penetration studies (%)

0.5-3.0

concentration dependent

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

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

Kidney, thyroid and blood toxicant
US EPA - possible human carcinogen

Handling issues

Property

Value and interpretation

General

Not explosive or oxidising
IMDG Transport Hazard Class 6.1
Not expected to auto-ignite; Not highly flammable

CLP classification 2013

Health: H302

WHO Classification

III (Slightly hazardous)

UN Number

UN2757

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

asulam

French

asulame

German

Asulam

Danish

asulam

Italian

asulame

Spanish

asulam

Greek

Polish

asulam

Swedish

Hungarian

aszulam

Dutch

asulam

Norwegian

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