Azamethiphos (Ref: GCA 18809)	Last updated: 31/12/2020
(Also known as: OMS 1825)

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SUMMARY

Azamethiphos is an organophosphate used as an insecticide and as an antiparasitic agent for veterinary use. It does not have EU approval for use. It is highly soluble in water, volatile and not expected to leach to groundwater. Not a great deal is known about its environmental persistence. It is modertaley toxic to mammals and not expected to bioaccumulate. It is a mutagen, neurotoxicant and an acetyl cholinesterase inhibitor. Azamethiphos is highly toxic to birds and aquatic invertebrates and moderately toxic to fish.

GENERAL INFORMATION

Description	A residual organophoshorus insecticide for fly control. Also has some applications in fish farming.
Example pests controlled	Houseflies; Beetles; Bugs; Spiders; Sea lice; Cockroaches; Tsetse flies
Example applications	Residences and other buildings
Efficacy & activity	-
Availability status	Current
Introduction & key dates	1970

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	Not applicable
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	Australia

Chemical structure

Isomerism	-
Chemical formula	C₉H₁₀ClN₂O₅PS
Canonical SMILES	COP(=O)(OC)SCN1C2=NC=C(C=C2OC1=O)Cl
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	VNKBTWQZTQIWDV-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C9H10ClN2O5PS/c1-15-18(14,16-2)19-5-12-8-7(17-9(12)13)3-6(10)4-11-8/h3-4H,5H2,1-2H3
2D structure diagram/image available?	Yes

General status

Pesticide type	Insecticide, Veterinary substance
Substance group	Organophosphate
Minimum active substance purity	>95%
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Contact and stomach action, rapid knockdown. Acetylcholinesterase (AChE) inhibitor.
CAS RN	35575-96-3
EC number	252-626-0
CIPAC number	8022
US EPA chemical code	-
PubChem CID	71482
Molecular mass	324.68
PIN (Preferred Identification Name)	S-[(6-chloro-2-oxo-1,3-oxazolo[4,5-b]pyridin-3(2H)-yl)methyl] O,O-dimethyl phosphorothioate
IUPAC name	S-6-chloro-2,3-dihydro-2-oxo-1,3-oxazolo[4,5-b]pyridin-3-ylmethyl O,O-dimethyl phosphorothioate
CAS name	S-[(6-chloro-2-oxooxazolo[4,5-b]pyridin-3(2H)-yl)methyl] O,O-dimethyl phosphorothioate
Other status information	-
Relevant Environmental Water Quality Standards	UK non-statutory standard for protection of freshwater and saltwater aquatic life 0.02 µg l⁻¹ as annual average, 0.05 as max acceptable conc.
Herbicide Resistance Classification (HRAC)	Not applicable
Herbicide Resistance Classification (WSSA)	Not applicable
Insecticide Resistance Classification (IRAC)	1B
Fungicide Resistance Classification (FRAC)	Not applicable
Examples of recorded resistance	Musca domestica
Physical state	Colourless to grey cystalline solid

Formulations

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Alfacron Snip Zazafly
Example products using this active	Syngenta Ciba-Geigy
Formulation and application details	Often supplied as a wettable powders, direct use bait formulations and as bath additives

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		1100	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source	High
Solubility - In organic solvents at 20 °C (mg l⁻¹)		610000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Dichloromethane	-
		130000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Benzene	-
		100000	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Methanol	-
		5800	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source n-Octanol	-
Melting point (°C)		89	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Boiling point (°C)		Decomposes before boiling	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		150	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Octanol-water partition coefficient at pH 7, 20 °C	P	1.12 X 1001	Calculated	-
	Log P	1.05	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Low
Bulk density (g ml⁻¹)		1.6	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Dissociation constant pKa) at 25 °C		-	-	-
		-
Vapour pressure at 20 °C (mPa)		0.0049	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source	Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		1.45 X 10-06	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Non-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)	0.25	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Non-persistent
	DT₅₀ (lab at 20 °C)	-	-	-
	DT₅₀ (field)	-	-	-
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	DT₅₀ modelling endpoint	-	-	-
	Note	Best available data, Industry data DT₅₀ in loamy sand circa 6 hours (E3)
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	11	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Non-persistent
	Note	pH sensitive ranging from 33 days at pH 5 to 4.3 hrs at pH 9
Water-sediment DT₅₀ (days)		-	-	-
Water phase only DT₅₀ (days)		-	-	-

Soil adsorption and mobility

Property		Value	Source; quality score; and other information	Interpretation
Linear	Kd	-	S1 S = Expert judgement 1 = Estimated data with little or no verification	Mobile
	Koc	25
	Notes and range	Estimated
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		-1.57	Calculated	Low leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate	Value	2.92 X 10-04	Calculated	-
	Note	-
Potential for particle bound transport index		Low	Calculated	-
Potential for loss via drain flow		Mobile	Calculated	-

ECOTOXICOLOGY

Property		Value	Source; quality score; and other information	Interpretation
Bio-concentration factor	BCF (l kg⁻¹)	1.56	Q2 Q = Miscellaneous internet resources 2 = Unverified data of unknown source Estimated	Low potential
	CT₅₀ (days)	Not available		-
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		1180	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	Moderate
Mammals - Short term dietary NOEL	(mg kg⁻¹)	2	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	High
	(ppm diet)	20		-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Birds - Acute LD₅₀ (mg kg⁻¹)		> 30.2	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Colinus virginianus	High
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Fish - Acute 96 hour LC₅₀ (mg l⁻¹)		> 0.115	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Oncorhynchus mykiss	Moderate
Fish - Chronic 21 day NOEC (mg l⁻¹)		-	-	-
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		0.00067	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Daphnia magna	High
Aquatic invertebrates - Chronic 21 day NOEC (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)		-	-	-
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)		-	-	-
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		-	-	-
Honeybees (Apis spp.)	Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	> 0.10	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	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)	-	-	-
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)		-	-	-
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)		1180	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	Moderate
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		2150	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		> 0.56	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Rat	-
Other Mammal toxicity endpoints		-	-	-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)		0.003	B5 B = UK CRD and ACP evaluation documents / and other Defra (UK) documents (click here ) 5 = Verified data used for regulatory purposes UK ACP 2001	-
ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)		0.01	B5 B = UK CRD and ACP evaluation documents / and other Defra (UK) documents (click here ) 5 = Verified data used for regulatory purposes UK ACP 2001	-
AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)		-	-	-
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)		0.1	B5 B = UK CRD and ACP evaluation documents / and other Defra (UK) documents (click here ) 5 = Verified data used for regulatory purposes UK ACP 2001 ST	-
Dermal penetration studies (%)		-	-	-
Dangerous Substances Directive 76/464		List I; List II	-	-
Exposure Routes	Public	-
	Occupational	-
European MRLs		EU MRL pesticide database
Drinking Water Standards		-	-	-
Drinking Water MAC (μg l⁻¹)		-	-	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor No data found A3 A = Chromosome aberration (EFSA database) 3 = Negative ; B3 B = DNA damage/repair (EFSA database) 3 = Negative ; C3 C = Gene mutation (EFSA database) 3 = Negative ; D0 D = Genome mutation (EFSA database) 0 = No data ; E1 E = Unspecified genotoxicity type (miscellaneous data source) 1 = Positive XNo, known not to cause a problem Reproduction / development effects Acetyl cholinesterase inhibitor Neurotoxicant No data found ✓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 ?Possibly, status not identified Eye irritant Phototoxicant   ✓Yes, known to cause a problem No data found
General human health issues		Mutagenic potential

Handling issues

Property	Value and interpretation
General	IMDG Transport Code is 6.1
CLP classification 2013	Health: H302, H317, H332 Environment: H400, H410
EC Risk Classification	Xn - Harmful: R22 Xi - Irritant: R36
EC Safety Classification	S26
WHO Classification	II (Moderately hazardous)
UN Number	2783
Waste disposal & packaging	-

TRANSLATIONS

Language	Name
English	azamethiphos
French	azametiphos
German	Azamethiphos
Danish	azamethiphos
Italian	azametifos
Spanish	azametifos
Greek	-
Polish	azametifos
Swedish	azametifos
Hungarian	-
Dutch	azamethifos

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Record last updated:	31/12/2020
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