Fonofos (Ref: N-2790)	Last updated: 01/02/2021
(Also known as: fonophos; dyfonate; difonate)

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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	Obsolete
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

Also used in

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 group	Organophosphate
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
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
Relevant Environmental Water Quality Standards	-
Herbicide Resistance Classification (HRAC)	Not applicable
Herbicide Resistance Classification (WSSA)	Not applicable
Insecticide Resistance Classification (IRAC)	Not known
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	Capfos Edge Tenax Tycap Dyfonate
Example products using this active	Stauffer Chemical Co. Zeneca
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)		13	K4 K = Research datasets, e.g. Pandora, Demetra 4 = Verified data	Low
Solubility - In organic solvents at 20 °C (mg l⁻¹)		Miscible	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Acetone	-
		Miscible	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Ethanol	-
		Miscible	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Xylene	-
		Miscible	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Kerosene	-
Melting point (°C)		Not applicable	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Boiling point (°C)		130	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	7.94 X 1003	Calculated	-
	Log P	3.9	G4 G = Extension Toxicology network database EXTOXNET (click here ) 4 = Verified data	High
Bulk density (g ml⁻¹)		1.17	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source	-
Dissociation constant pKa) at 25 °C		-	-	-
		-
Vapour pressure at 20 °C (mPa)		27	K4 K = Research datasets, e.g. Pandora, Demetra 4 = Verified data	Highly volatile
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		6.56 X 10-01	H4 H = The US ARS pesticide properties database (click here ) 4 = Verified data	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)	99	K4 K = Research datasets, e.g. Pandora, Demetra 4 = Verified data	Moderately persistent
	DT₅₀ (lab at 20 °C)	99	K4 K = Research datasets, e.g. Pandora, Demetra 4 = Verified data	Moderately persistent
	DT₅₀ (field)	40	F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source	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	38	K3 K = Research datasets, e.g. Pandora, Demetra 3 = Unverified data of known source	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	Kd	-	G3 G = Extension Toxicology network database EXTOXNET (click here ) 3 = Unverified data of known source	Slightly mobile
	Koc	870
	Notes and range	-
Freundlich	Kf	-	-	-
	Kfoc	-
	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	-

ECOTOXICOLOGY

Property		Value	Source; quality score; and other information	Interpretation
Bio-concentration factor	BCF (l kg⁻¹)	300	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source Estimated	Threshold for concern
	CT₅₀ (days)	Not available		-
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		6.8	G4 G = Extension Toxicology network database EXTOXNET (click here ) 4 = Verified data 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	G4 G = Extension Toxicology network database EXTOXNET (click here ) 4 = Verified data Anas platyrhynchos	Moderate
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		0.028	G4 G = Extension Toxicology network database EXTOXNET (click here ) 4 = Verified data Lepomis macrochirus	High
Fish - Chronic 21 day NOEC (mg l⁻¹)		> 0.0023	P3 P = Other governments and regulators 3 = Unverified data of known source Lepomis macrochirus 30 day	High
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		0.0023	F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source Daphnia magna	High
Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)		> 0.0003	P3 P = Other governments and regulators 3 = Unverified data of known source Daphnia magna	High
Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)		0.00041	F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source Americamysis bahia	High
Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)		0.039	F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source 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)		-	-	-
Non-target plants		-	-	-
		-	-	-
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)		1.5	K2 K = Research datasets, e.g. Pandora, Demetra 2 = Unverified data of unknown source Unknown species	Moderate
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		0.5	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source Unknown species	Moderate
Honeybees (Apis spp.)	Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	> 3.3	K4 K = Research datasets, e.g. Pandora, Demetra 4 = Verified data	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	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	High
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	-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)		218	K4 K = Research datasets, e.g. Pandora, Demetra 4 = Verified data	Moderate
Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)		-	-	-
Other soil macro-organisms	Acute LC₅₀ (mg kg⁻¹)	-	-	-
	Chronic NOEC (mg kg⁻¹)	-	-	-
Other arthropod (1)	LR₅₀ g ha⁻¹	-	-	-
	% Effect	-	-	-
Other arthropod (2)	LR₅₀ g ha⁻¹	-	-	-
	% Effect	-	-	-
Soil micro-organisms		-	-	-
Mesocosm study data	NOEAEC mg l⁻¹	-	-	-
	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	G4 G = Extension Toxicology network database EXTOXNET (click here ) 4 = Verified data Rat	High
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		147	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source 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	G3 G = Extension Toxicology network database EXTOXNET (click here ) 3 = Unverified data of known source	-
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
	Notes	-
Drinking Water Standards		-	-	-
Drinking Water MAC (μg l⁻¹)		-	-	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor XNo, known not to cause a problem A0 A = Chromosome aberration (EFSA database) 0 = No data ; B0 B = DNA damage/repair (EFSA database) 0 = No data ; C0 C = Gene mutation (EFSA database) 0 = No data ; D0 D = Genome mutation (EFSA database) 0 = No data ; E3 E = Unspecified genotoxicity type (miscellaneous data source) 3 = Negative No data found Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant ?Possibly, status not identified ✓Yes, known to cause a problem ✓Yes, known to cause a problem Respiratory tract irritant Skin irritant Skin sensitiser No data found XNo, known not to cause a problem No data found Eye irritant Phototoxicant   XNo, known not to cause a problem No data found
General human health issues		Highly toxic Ingestion may cause nausea, abdominal cramps, and diarrhea

Handling issues

Property	Value and interpretation
General	No information available
CLP classification 2013	Health: H300, H310 Environment: H400, H410
EC Risk Classification	T+ - Very toxic: R27/28 N - Dangerous for the environment: R50, R53
EC Safety Classification	S1/2, S26, S36/37, S45, S60, S61
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

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Record last updated:	01/02/2021
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