Azinphos-methyl

Azinphos-methyl	Last updated: 23/01/2025
(Also known as: azinphosmethyl; metiltriazotion; cotnion methyl; gusathion methyl)

SUMMARY

Azinphos-methyl is an organophosphate insecticide. It has a moderate aqueous solubility, is volatile and not expected to leach to groundwater. It is generally not persistent in soil or water systems. Azinphos-methyl is highly toxic to mammals but is not expected to bioaccumulate. It is a neurotoxicant and an acetyl cholinesterase inhibitor. It is highly toxic to birds, honeybees and most aquatic life. It is moderately toxic to 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 Moderate alert: Moderately persistent; Drainflow: Slightly mobile; Potential for particle bound transport: Medium	Ecotoxicity High alert: Birds acute ecotoxicity: High; Fish acute ecotoxicity: High; Fish chronic ecotoxicity: High; Daphnia acute ecotoxicity: High; Daphnia chronic ecotoxicity: High; Bees acute contact ecotoxicity: High	Human health High alert: Mammals acute toxicity: High; Acetyl cholinesterase inhibitor; Neurotoxicant

GENERAL INFORMATION

Description

An organophosphorus insecticide for the control of sucking and chewing pests

Example pests controlled

Mites, Ticks, Aphids; Slugs; Snails

Example applications

Lowland rice; Fruit; vegetables; Tobacco; Nuts; Ornamentals

Efficacy & activity

Availability status

Current

Introduction & key dates

1955, 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 pesticide

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Not approved

Dossier rapporteur/co-rapporteur

Germany

Date EC 1107/2009 inclusion expires

Expired

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, USA

Chemical structure

Isomerism

None

Chemical formula

C₁₀H₁₂N₃O₃PS₂

Canonical SMILES

COP(=S)(OC)SCN1C(=O)C2=CC=CC=C2N=N1

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

CJJOSEISRRTUQB-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C10H12N3O3PS2/c1-15-17(18,16-2)19-7-13-10(14)8-5-3-4-6-9(8)11-12-13/h3-6H,7H2,1-2H3

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
azinphos-methyl	-

General status

Pesticide type

Insecticide, Acaricide, Molluscicide

Substance groups

Organophosphate Insecticide; Organophosphate acaricide; Organothiophosphate insecticide; Organothiophosphate acaricide

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Non-systemic, contact and stomach action. Acetylcholinesterase (AchE) inhibitor

CAS RN

86-50-0

EC number

201-676-1

CIPAC number

US EPA chemical code

058001

PubChem CID

2268

CLP index number

015-039-00-9

Molecular mass

317.32

PIN (Preferred Identification Name)

O,O-dimethyl S-[(4-oxo-1,2,3-benzotriazin-3(4H)-yl)methyl] phosphorodithioate

IUPAC name

S-3,4-dihydro-4-oxo-1,2,3-benzotriazin-3-ylmethyl O,O-dimethyl phosphorodithioate

CAS name

O,O-dimethyl S-[(4-oxo-1,2,3-benzotriazin-3(4H)-yl)methyl] phosphorodithioate

Other status information

Potential groundwater contaminant; Severe Marine Pollutant; Chemical subject to PIC regulations; PAN Bad Actor Chemical; Subject to the provisions of the UK Poisons Act 1972

Relevant Environmental Water Quality Standards

UK statutory standard for protection of inland, coastal and territorial waters for aquatic life 0.01 µg l⁻¹ as annual average

Herbicide Resistance Class (HRAC MoA class)

Not applicable

Herbicide Resistance Class (WSSA MoA class)

Not applicable

Insecticide Resistance Class (IRAC MoA class)

Fungicide Resistance Class (FRAC MOA class)

Not applicable

Examples of recorded resistance

Predatory mites, Aphids, Lacewings, Codling moth, Leaf miners, plus others

Physical state

White crystals

Related substances & organisms

azinphos-ethyl

Formulations

Property

Value

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

Makhteshim Agan
General Quimica S.A.
Bayer
Mobay

Example products using this active

Gusathion M
Co-thion
Azinpaz
Carfene
Guthion

Formulation and application details

Usually supplied as concentrate suspensions, liquids and wettable powders

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

Moderate

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

250000

Acetone

250000

Ethyl acetate

170000

Xylene

1200

n-Heptane

Melting point (°C)

Boiling point (°C)

Decomposes before boiling

Degradation point (°C)

200

Flashpoint (°C)

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

9.12 X 10⁰²

Calculated

Log P

2.96

Moderate

Fat solubility of residues

Solubility

Soluble

Data type

Regulatory data - observed in metabolism and farm animal feeding studies

Density (g ml⁻¹)

1.52

Dissociation constant pKa) at 25 °C

Weak acid

Vapour pressure at 20 °C (mPa)

5.00 X 10^-04

Low volatility

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

5.70 X 10^-06

Non-volatile

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

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

Not readily biodegradable

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Non-persistent

DT₅₀ (lab at 20 °C)

Moderately persistent

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

Dissipation rate RL₅₀ (days) on plant matrix

Value

8.7

Note

Published literature RL₅₀ range 1.0-30.0 days, 8 field crops, various matrices, n=11; Apples & lemons in cold storage RL₅₀ range 46-122 days

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

8.8

Note

Published literature RL₅₀ range 4.0-16.0 days, 6 field crops, various matrices, n=6

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Moderately fast

Note

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

Value

Moderately persistent

Note

DT₅₀ 87 days at pH 4, 4 days at pH 9

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)

10.9

Slightly mobile

K_oc (mL g⁻¹)

1112

Notes and range

EU dossier K_d range 3.33-28.5 mL g⁻¹, K_oc range 425-1282 mL g⁻¹, Soils=10

Freundlich

K_f (mL g⁻¹)

K_foc (mL g⁻¹)

¹/_n

Notes and range

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.42

Calculated

Low leachability

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

Value

3.40 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

Bio-concentration factor

BCF (l kg⁻¹)

Low potential

CT₅₀ (days)

Not available

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

Rat

High

Mammals - Short term dietary NOEL

(mg kg⁻¹)

Rat 2 yr

(ppm diet)

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

Birds - Acute LD₅₀ (mg kg⁻¹)

Colinus virginianus

High

Birds - Short term dietary (LC₅₀/LD₅₀)

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

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

Moderate

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)

0.42

High

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

Notes

[The residual time to 25% mortality (RT25) value for honeybees is 312 hrs - USEPA data]

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) as Mortality, Contact LC₅₀ ppm

> 39.3

Chrysoperla carnea Larva

Beneficial insects (Parasitic wasps)

Beneficial insects (Predatory mites)

Harmful at dose 300 g ha⁻¹

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)

> 0.02

Oncorhynchus mykiss

High

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

0.00017

Pimephales promelas

High

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

> 0.0091

Danio rerio

High

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

0.0011

Daphnia magna

High

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

0.0004

Daphnia magna LOEC

High

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

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

0.00022

Americamysis bahia

High

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)

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

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

7.15

Raphidocelis subcapitata

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)

Rat

High

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

175

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.15

Rat

Other Mammal toxicity endpoints

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

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

List I; List II

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

Eliminated in faeces and urine of mammals within 2 days of administration.

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

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

No further information available

Handling issues

Property

Value and interpretation

General

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

CLP classification 2013

Health: H300, H311, H317, H330
Environment: H400, H410

WHO Classification

Ib (Highly hazardous)

UN Number

UN2783

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

azinphos-methyl

French

azinphos-methyle

German

Azinphos-methyl

Danish

azinphos-methyl

Italian

azinfos-metile

Spanish

azinfos-metil

Greek

azinphos-methyl

Polish

azinofos metylowy

Swedish

azinfosmetyl

Hungarian

azinphos-metil

Dutch

azinfos-methyl

Norwegian

Record last updated:	23/01/2025
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