Fosthiazate (Ref: IKI 1145)

Fosthiazate (Ref: IKI 1145)	Last updated: 22/05/2025
(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: GUS: Transition state; Drainflow: Moderately mobile	Ecotoxicity High alert: Birds acute ecotoxicity: High; Birds chronic ecotoxicity: High; Bees acute contact ecotoxicity: High; Bees acute oral ecotoxicity: High	Human health High alert: Mammals acute toxicity: High; Mammals chronic toxicity: High; Reproduction/development effects; Acetyl cholinesterase inhibitor; Neurotoxicant

GENERAL INFORMATION

Description

A soil applied nematicide and insecticide used to control nematodes and sucking / chewing ground insects

Example pests controlled

Potato Cyst Nematode (Globodera rostochiensis, Globodera pallida); Wireworms; Root Knot Nematode (Meloidogne spp.)

Example applications

Potatoes; Tomatoes; Vegetables

Efficacy & activity

Effectiveness has been established via a long period of use in practice in many European countries.

Availability status

Current

Introduction & key dates

1992, launched Japan; 2004, first registered USA

GB regulatory status

GB COPR regulatory status

Approved

Date COPR inclusion expires

31/10/2029

GB LERAP status

None

EC Regulation 1107/2009 (repealing 91/414)

EC Regulation 1107/2009 status

Approved

Dossier rapporteur/co-rapporteur

Germany/Greece

Date EC 1107/2009 inclusion expires

31/01/2027

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

Morocco

Chemical structure

Isomerism

A molecule with 2 chiral centres giving four stereoisomers

Chemical formula

C₉H₁₈NO₃PS₂

Canonical SMILES

CCC(C)SP(=O)(N1CCSC1=O)OCC

Isomeric SMILES

International Chemical Identifier key (InChIKey)

DUFVKSUJRWYZQP-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C9H18NO3PS2/c1-4-8(3)16-14(12,13-5-2)10-6-7-15-9(10)11/h8H,4-7H2,1-3H3

2D structure diagram/image available?

Yes

General status

Pesticide type

Insecticide; Nematicide

Substance groups

Organophosphate insecticide; Organophosphate nematicide; Organothiophosphate insecticide; Organothiophosphate nematicide

Minimum active substance purity

930 g kg⁻¹

Known relevant impurities

EU dossier - None declared

Substance origin

Synthetic

Mode of action

Systemic. Acetylcholinesterase (AchE) inhibitor.

CAS RN

98886-44-3

EC number

619-377-3

CIPAC number

585

US EPA chemical code

129022

PubChem CID

91758

CLP index number

015-168-00-0

Molecular mass

283.35

PIN (Preferred Identification Name)

IUPAC name

(RS)-[S-(RS)-sec-butyl O-ethyl 2-oxo-1,3-thiazolidin-3-ylphosphonothioate]

CAS name

O-ethyl S-(1-methylpropyl) (2-oxo-3-thiazolidinyl)phosphonothioate

Other status information

Relevant Environmental Water Quality Standards

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

None identified

Physical state

Clear colourless liquid at 99% purity. Colour darkens towards yellow as purity decreases.

Formulations

Property

Value

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

Syngenta

Example products using this active

Nemathorin
Premier
Prime

Formulation and application details

Often supplied as fine granules applied directly to the soil

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

9000

High

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

15100

Hexane

250000

Acetone

250000

Methanol

214000

Ethyl acetate

Melting point (°C)

Not applicable

Boiling point (°C)

198

Degradation point (°C)

255

Flashpoint (°C)

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

4.79 X 10⁰¹

Calculated

Log P

1.68

at 25°C

Low

Fat solubility of residues

Solubility

Insoluble

Data type

Regulatory data

Density (g ml⁻¹)

1.23

Dissociation constant pKa) at 25 °C

Not applicable

No dissociation

Vapour pressure at 20 °C (mPa)

0.56

Low volatility. If applied directly to plants, drift is a concern & mitigation is advisable

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

1.76 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

Maxima circa 290 nm, 220nm = 5900

Surface tension (mN m⁻¹)

Degradation

Property

Value

Source; quality score; and other information

Interpretation

General biodegradability

Soil degradation (days) (aerobic)

DT₅₀ (typical)

26.8

Non-persistent

DT₅₀ (lab at 20 °C)

26.8

Non-persistent

DT₅₀ (field)

10.3

Non-persistent

DT₉₀ (lab at 20 °C)

107.6

Persistent

DT₉₀ (field)

47.0

DT₅₀ modelling endpoint

Note

EU 2023 dossier lab studies DT₅₀ (normalised) range 11.5-70.3 days, DT₉₀ (measured) range 38.1-256 days, Soils=6; field studies DT₅₀ (normalised) range 6.8-13.6 days, DT₉₀ (measured) range 30.6-60.3 days, Soils=5

Dissipation rate RL₅₀ (days) on plant matrix

Value

Note

Dissipation rate RL₅₀ (days) on and in plant matrix

Value

1.7

Note

Tomato fruit, n=1

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Stable

Note

Not a significant degradation route

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

Value

104

Persistent

Note

pH sensitive: DT₅₀ 177 days at pH 5, 3.2 days at pH 9, all at 25 °C

Water-sediment DT₅₀ (days)

Moderately fast

Water phase only DT₅₀ (days)

Slow

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)

1.97

Moderately mobile

K_oc (mL g⁻¹)

239

Notes and range

Literature data: K_d range 1.48-2.77 mL g⁻¹; K_oc range 162.0-286.7 mL g⁻¹, Soils=9

Freundlich

K_f (mL g⁻¹)

0.84

Mobile

K_foc (mL g⁻¹)

55.6

¹/_n

0.95

Notes and range

EU 2023 dossier K_f range 0.426-1.63 mL g⁻¹, K_foc range 30.4-97.4 mL g⁻¹, ¹/_n range 0.87-1.09, Soils=7; Literature data: K_f range 0.10-2.75 mL g⁻¹; K_foc range 16.9-286 mL g⁻¹, ¹/_n range 0.763-1.111, Soils=12 (R4)

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

2.28

Calculated

Transition state

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

Value

4.89 X 10^-02

Calculated

Note

Potential for particle bound transport index

Low

Calculated

Potential for loss via drain flow

Moderately mobile

Calculated

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

1.464

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)

3.2

Whole fish

Low potential

CT₅₀ (days)

Not available

Known soil metabolites

Metabolite

Major/Minor fraction

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

Estimated maximum occurrence fraction

Notes

2-butanesulfonic acid

Major fraction

0.198

N-[butan-2-ylsulfanyl(ethoxy)phosphoryl]-2-methylsulfonylethanamine (Ref: SDS-67131)

LC50(Worms) 14day: >1000 mg/kg

(RS)-S-sec-butyl O-ethyl-N-(2-ethylsulfonylethyl)-phosphoramidothioate; BESoP

Minor fraction

0.016

sec-butyl methylsulfone

Major fraction

0.107

1,3-thiazolidin-2-one

Major fraction

0.166

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)

2-butanesulfonic acid; BSA

Not relevant

(RS)-S-sec-butyl O-ethyl-N-(2-ethylsulfonylethyl)-phosphoramidothioate

Not relevant

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

3-methylsulfonyl 2-butanol
Note: EFSA, 2023

HMBS

Animal; Rat; Plant

sec-butyl methylsulfone
Note: EFSA, 2023

MBSo

Animal; Surface water; Sediment

(RS)-S-sec-butyl alcoholhydrogen phosphorothioate
Note: EFSA, 2023

DEDT

Plant

sec-butyl methylsulfoxide
Note: EFSA, 2023

MBSx

Plant; Surface water; Sediment

O-ethyl S-hydrogen N-2-(methylsulfonyl)ethylphosphoramidothioate
Note: EFSA, 2023

DBSoS

Rat

O-ethyl O-hydrogen N-2-(methylsulfonyl)ethylphosphoramidate
Note: EFSA, 2023

DBSoO

Rat

O-ethyl O-hydrogen N-2-(methylsulfinyl)ethylphosphoramidate
Note: EFSA, 2023

DBSxO

Rat

O-ethyl S-hydrogen N-2-(methylsulfinyl)ethylphosphoramidothioate
Note: EFSA, 2023

DBSxS

Rat

(RS)-S-sec-butylO-ethylN-(2-methylsulfinylethyl)phosphoramid othioate
Note: EFSA, 2023

BESxP

Rat

(RS)-S-sec-butyl O-ethyl N-(2-sulfoethyl)phosphoramidothioate
Note: EFSA, 2023

BESaP

Rat; Hen

o-ethyl-2-oxo-1,3-thiazolidin-3-ylphosphonate
Note: EFSA, 2023

DBTO

Rat; Plant

(RS)-S-sec-butyl O-ethyl-N-(2-ethylsulfonylethyl)-phosphoramidothioate
Note: EFSA, 2023

BESoP

Rat; Plant

O-ethyl O-hydrogen 2-oxo-1,3-thiazolidin-3-ylphosphonothioate
Note: EFSA, 2023

DBTS

Rat; Plant

3-aminophenyl N methylcarbamate
Note: EFSA, 2023

BSA

Rat; Plant; Surface water; Sediment

1,3-thiazolidin-2-one
Note: EFSA, 2023

TZO

Water (Hydrolysis)

(RS)-s-sec-butyl-o-ethylphosphorothioate
Note: EFSA, 2023

DTTO

Plant; Surface water; Sediment

RS)-s-sec-butyl-2-oxo-1,3-thiazolidin-3-ylphosphonothioate
Note: EFSA, 2023

DETO

Plant; Surface water; Sediment

glucose conjugate of 3-hydroxy 2-butanesulfonic acid
Note: EFSA, 2023

Glc-HBSA

Plant

glucose conjugate of 3-methylsulfonyl 2-butanol
Note: EFSA, 2023

Glc-HMBS

Plant

3-hydroxy 2-butanesulfonic acid
Note: EFSA, 2023

HBSA

Rat; Plant

3-methylsulfonyl 2-butanol
Note: EFSA, 2023

HMBS

Rat; Animal; Plant

1,3-thiazolidin-2-one
Note: EFSA, 2023

TZO

Rat; Plant; Surface water; Sediment

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)

0.5

Dog

High

(ppm diet)

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

0.7

Unknown species Reproductive NOAEL

High

Birds - Acute LD₅₀ (mg kg⁻¹)

Colinus virginianus

High

Birds - Short term dietary (LC₅₀/LD₅₀)

139 ppm

Colinus virginianus

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

2.5

Colinus virginianus

High

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

209

Eisenia foetida

Moderate

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

Eisenia foetida

Moderate

Soil micro-organisms

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

Dose: 53 mg kg⁻¹ soil 60 Day

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

1.47

Folsomia candida

Non-target plants

Honeybees (Apis spp.)

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

0.256

Apis mellifera

High

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

0.61

Apis mellifera

High

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

Chronic 10d LD₅₀

0.05

Apis mellifera

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

0.48

Aphidius rhopalosiphi

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

2.1

Typhlodromus pyri

Beneficial insects (Ground beetles)

3.4% Mortality at dose 3 kg ha⁻¹

Poecilus cupreus

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

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

114

Oncorhynchus mykiss

Low

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

2.4

Oncorhynchus mykiss

Moderate

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

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

0.282

Daphnia magna

Moderate

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

0.06

Daphnia magna

Moderate

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

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

0.429

Americamysis bahia

Moderate

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

0.1

Chironomus riparius

Moderate

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)

> 4.51

Selenastrum capricornutum

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)

861

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

0.56

Rat

Other Mammal toxicity endpoints

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

0.004

Rat SF=100

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

0.007

Dog SF=100

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

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

0.005

Dog 90 day SF=100

Dermal penetration studies (%)

10.0

Dangerous Substances Directive 76/464

List I; List II

Exposure Routes

Public

Minimal risk of dietary exposure
Negligible risk to bystanders

Occupational

PPE/PPC use is advised

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

Rapidly excreted; >80% via urine and air within 48 hrs

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

No data found

General human health issues

Potential adrenal toxicant

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: H301, H311, H319, H317, H331, H362, H361d, H361f, H370, H373
Environment: H400, H410

WHO Classification

Not listed (Not listed)

UN Number

UN3018

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

fosthiazate

French

fosthiazate

German

Fosthiazat

Danish

fosthiazat

Italian

fostiazate

Spanish

fostiazato

Greek

Polish

fostiazat

Swedish

Hungarian

fosztiazat

Dutch

fosthiazaat

Norwegian

Record last updated:	22/05/2025
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