Fonofos (Ref: N-2790)

Fonofos (Ref: N-2790)	Last updated: 17/01/2023
(Also known as: fonophos; dyfonate; difonate)

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; Drainflow: Slightly mobile; Potential for particle bound transport: Medium	Ecotoxicity High alert: Fish acute ecotoxicity: High; Fish chronic ecotoxicity: High; Daphnia acute ecotoxicity: High; Daphnia chronic ecotoxicity: High; Bees acute unknown ecotoxicity: High	Human health High alert: Mammals acute toxicity: High; Acetyl cholinesterase inhibitor; Neurotoxicant

GENERAL INFORMATION

Description

An obsolete soil acting insecticide once used on various crops but predominately corn to control various sucking pests

Example pests controlled

Aphids, Corn rootworm; Wireworm; Cutworms; White grubs; Corn maggots; Symphylans

Example applications

Vegetables including asparagus, beans, onions, peppers, sweet potatoes; Ornamentals; Corn; Turf and lawns

Efficacy & activity

Availability status

Considered obsolete but may be available in some countries

Introduction & key dates

1965, first reported

UK regulatory status

UK COPR regulatory status

Not approved

Date COPR inclusion expires

Expired

UK LERAP status

No UK approval for use

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)

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

Additional information

Also used in

USA

Chemical structure

Isomerism

A chiral molecule existing in the R- and S-forms. The R-isomer is more biologically active than the S-isomer.

Chemical formula

C₁₀H₁₅OPS₂

Canonical SMILES

CCOP(=S)(CC)SC1=CC=CC=C1

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

KVGLBTYUCJYMND-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C10H15OPS2/c1-3-11-12(13,4-2)14-10-8-6-5-7-9-10/h5-9H,3-4H2,1-2H3

2D structure diagram/image available?

Yes

General status

Pesticide type

Insecticide

Substance groups

Organophosphate insecticide; Phenyl ethylphosphonothioate insecticide

Minimum active substance purity

>99.5%

Known relevant impurities

Substance origin

Synthetic

Mode of action

Cholinesterase inhibitor. Non-systemic with contact and stomach action.

CAS RN

944-22-9

Alternative/old CAS RN

66767-39-3; 62705-71-9; 62680-03-9

EC number

213-408-0

CIPAC number

306

US EPA chemical code

041701

PubChem CID

13676

CLP index number

015-091-00-2

Molecular mass

246.3

PIN (Preferred Identification Name)

IUPAC name

(RS)-O-ethyl S-phenyl ethylphosphonodithioate

CAS name

O-ethyl S-phenyl ethylphosphonodithioate

Other status information

Potential groundwater contaminant; Severe Marine Pollutant; Subject to the provisions of the UK Poisons Act 1972

Relevant Environmental Water Quality Standards

Herbicide Resistance Classification (HRAC)

Not applicable

Herbicide Resistance Classification (WSSA)

Not applicable

Insecticide Resistance Classification (IRAC)

Fungicide Resistance Classification (FRAC)

Not applicable

Examples of recorded resistance

Delia antiqua, Diabrotica undecimpunctata, Sedes nigromaculis, Diabrotica virgifera

Physical state

Clear colourless to yellow coloured liquid

Formulations

Property

Value

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

Stauffer Chemical Co.
Zeneca

Example products using this active

Capfos
Edge
Tenax
Tycap
Dyfonate

Formulation and application details

Available in a wide variety of different formulations including granules, suspension concentrates and seed treatments

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

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

Low

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

Miscible

Acetone

Miscible

Ethanol

Miscible

Xylene

Miscible

Kerosene

Melting point (°C)

Not applicable

Boiling point (°C)

130

Degradation point (°C)

Flashpoint (°C)

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

7.94 X 10⁰³

Calculated

Log P

3.9

High

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

1.17

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

Highly volatile

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

6.56 X 10^-01

Moderately volatile

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

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Moderately persistent

DT₅₀ (lab at 20 °C)

Moderately persistent

DT₅₀ (field)

Moderately persistent

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

DT₅₀ modelling endpoint

Note

General literature DT₅₀ range 48-150 days (R2)

Dissipation rate RL₅₀ on plant matrix

Value

Note

Dissipation rate RL₅₀ 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

Moderately persistent

Note

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d

Slightly mobile

K_oc

870

Notes and range

Freundlich

K_f

K_foc

¹/_n

Notes and range

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

1.70

Calculated

Low leachability

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

Value

5.08 X 10^-02

Calculated

Note

Potential for particle bound transport index

Medium

Calculated

Potential for loss via drain flow

Slightly mobile

Calculated

Bio-concentration factor

BCF (l kg⁻¹)

300

Estimated

Threshold for concern

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)

6.8

Rat

High

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)

128

Anas platyrhynchos

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

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

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

218

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)

> 3.3

Moderate

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)

0.0087

High

Chronic

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 pollinators (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other pollinators (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)

Beneficial insects (Predatory mites)

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

0.028

Lepomis macrochirus

High

Fish - Chronic 21 day NOEC (mg l⁻¹)

> 0.0023

Lepomis macrochirus 30 day

High

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

0.0023

Daphnia magna

High

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

> 0.0003

Daphnia magna

High

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

0.00041

Americamysis bahia

High

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

0.039

Chironomus riparius 2 day

High

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 - Acute 7 day EC₅₀, biomass (mg l⁻¹)

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

1.5

Unknown species

Moderate

Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)

0.5

Unknown species

Moderate

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)

6.8

Rat

High

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

147

Rat

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

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

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

0.002

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

May be absorbed through the skin

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

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Highly toxic
Ingestion may cause nausea, abdominal cramps, and diarrhoea

Handling issues

Property

Value and interpretation

General

No information available

CLP classification 2013

Health: H300, H310
Environment: H400, H410

WHO Classification

Ia (Extremely hazardous)

UN Number

Waste disposal & packaging

TRANSLATIONS

Language

Name

English

fonofos

French

fonofos

German

Fonofos

Danish

fonofos

Italian

fonofos

Spanish

fonofos

Greek

fonofos

Polish

fonofos

Swedish

fonofos

Hungarian

fonofos

Dutch

fonofos

Record last updated:	17/01/2023
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