Ametryn (Ref: G 34162 )	Last updated: 13/01/2023
(Also known as: ametryne; ametrex)

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SUMMARY

Ametyn is a triazine herbicide. It is moderately soluble in water but much more so in organic solvents. It is quite volatile and not expected to leach to groundwater. It is moderately persistant in soils and can persist for a long time in water under certain conditions. It is moderately toxic to mammals and a recognised irritant. Ametryn is moderately toxic to most aquatic organisms, honey bees and earthworms but less so to birds.

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: Moderately mobile; Potential for particle bound transport: Medium	Ecotoxicity Moderate alert: Fish acute ecotoxicity: Moderate; Fish chronic ecotoxicity: Moderate; Daphnia acute ecotoxicity: Moderate; Daphnia chronic ecotoxicity: Moderate; Earthworms acute ecotoxicity: Moderate	Human health Moderate alert: Mammals acute toxicity: Moderate Warning: Significant data are missing

GENERAL INFORMATION

Description	A triazine herbicide used to control most annual and broad-leaved weeds
Example pests controlled	Burmuda grass, wiregrass, goosegrass, crabgrass and other grass weeds; Broad-leaved weeds including dallisgrass, thistle, purslane, pigweed, cocklebur, lambsquarters, morning glory and foxtail
Example applications	Fruit including citrus, bananas; Corn; Potatoes; Sugarbeet
Efficacy & activity	-
Availability status	Current
Introduction & key dates	1964, first registered USA

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	Australia

Chemical structure

Isomerism	None
Chemical formula	C₉H₁₇N₅S
Canonical SMILES	CCNC1=NC(=NC(=N1)SC)NC(C)C
Isomeric SMILES	No data
International Chemical Identifier key (InChIKey)	RQVYBGPQFYCBGX-UHFFFAOYSA-N
International Chemical Identifier (InChI)	InChI=1S/C9H17N5S/c1-5-10-7-12-8(11-6(2)3)14-9(13-7)15-4/h6H,5H2,1-4H3,(H2,10,11,12,13,14)
2D structure diagram/image available?	Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
ametryn monohydrate	Variant

General status

Pesticide type	Herbicide
Substance groups	Triazine herbicide
Minimum active substance purity	96%
Known relevant impurities	-
Substance origin	Synthetic
Mode of action	Selective, systemic absorbed through foliage and roots. Inhibits photosynthesis (photosystem II).
CAS RN	834-12-8
EC number	212-634-7
CIPAC number	133
US EPA chemical code	080801
PubChem CID	13263
CLP index number	613-010-00-0
Molecular mass	227.12
PIN (Preferred Identification Name)	N2-ethyl-6-(methylsulfanyl)-N4-(propan-2-yl)-1,3,5-triazine-2,4-diamine
IUPAC name	N2-ethyl-N4-isopropyl-6-methylthio-1,3,5-triazine-2,4-diamine
CAS name	N-ethyl-N'-(1-methylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine
Other status information	Chemical subject to PIC regulations
Relevant Environmental Water Quality Standards	-
Herbicide Resistance Classification (HRAC)	C1
Herbicide Resistance Classification (WSSA)	5
Insecticide Resistance Classification (IRAC)	Not applicable
Fungicide Resistance Classification (FRAC)	Not applicable
Examples of recorded resistance	-
Physical state	White powder

Formulations

Property	Value
Example manufacturers & suppliers of products using this active now or historically	Syngenta Crop Protection FCC King Tech Corp Ciba-Geigy Makhteshim-Agan
Example products using this active	Ametrex Evik Gesapax Almulex Duroplant Acetotrene Herbicide
Formulation and application details	Available in a range of formulations including emulsifiable concentrates, flowable concentrates and wettable powders.

ENVIRONMENTAL FATE

Property		Value	Source; quality score; and other information	Interpretation
Solubility - In water at 20 °C (mg l⁻¹)		200	H4 H = The US ARS pesticide properties database (click here ) 4 = Verified data	Moderate
Solubility - In organic solvents at 20 °C (mg l⁻¹)		56900	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Acetone	-
		1400	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source n-Hexane	-
		4600	R3 R = Peer reviewed scientific publications 3 = Unverified data of known source Toluene	-
Melting point (°C)		86.7	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source	-
Boiling point (°C)		337	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source	-
Degradation point (°C)		-	-	-
Flashpoint (°C)		-	-	-
Octanol-water partition coefficient at pH 7, 20 °C	P	4.27 X 1002	Calculated	-
	Log P	2.63	H4 H = The US ARS pesticide properties database (click here ) 4 = Verified data	Low
Fat solubility of residues	Solubility	-	-	-
	Data type	-	-	-
Density (g ml⁻¹)		1.18	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
Dissociation constant pKa) at 25 °C		10.07	DW4 DW = Don Wauchope personal database for Pka data: Wauchope, R. D. and Edwards, J. Dissociation constants for pesticide active ingredients: a database and comparison with predicted values. MS in preparation 4 = Verified data	-
		Very weak acid
Vapour pressure at 20 °C (mPa)		0.365	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)		4.10 X 10-04	H4 H = The US ARS pesticide properties database (click here ) 4 = Verified data	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)	37	H4 H = The US ARS pesticide properties database (click here ) 4 = Verified data	Moderately persistent
	DT₅₀ (lab at 20 °C)	60	Q3 Q = Miscellaneous internet resources 3 = Unverified data of known source	Moderately persistent
	DT₅₀ (field)	37	H4 H = The US ARS pesticide properties database (click here ) 4 = Verified data	Moderately persistent
	DT₉₀ (lab at 20 °C)	-	-	-
	DT₉₀ (field)	-	-	-
	DT₅₀ modelling endpoint	-	-	-
	Note	Other sources: DT₅₀ 70-120 days (R3)
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	-	W4 W = French database provided by ARVALIS-Institut du Végétal 4 = Verified data	-
	Note	Slow degradation in UV light
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7	Value	Stable	W4 W = French database provided by ARVALIS-Institut du Végétal 4 = Verified data	Stable
	Note	Stable to hydrolysis except at extreme pH values e.g. pH 0-1 and pH 13-14.
Water-sediment DT₅₀ (days)		-	-	-
Water phase only DT₅₀ (days)		-	-	-

Soil adsorption and mobility

Property		Value	Source; quality score; and other information	Interpretation
Linear	Kd	-	H3 H = The US ARS pesticide properties database (click here ) 3 = Unverified data of known source	Moderately mobile
	Koc	316
	Notes and range	General literature Koc range 170-390 mL g⁻¹
Freundlich	Kf	76.81	R4 R = Peer reviewed scientific publications 4 = Verified data	Non-mobile
	Kfoc	5115
	1/n	0.86
	Notes and range	Kf range 1.35-194.6 mL g⁻¹, Kfoc range 38.6-14969 mL g⁻¹, 1/n range 0.60-1.22, Soils=3
pH sensitivity		-

Fate indices

Property		Value	Source; quality score; and other information	Interpretation
GUS leaching potential index		0.46	Calculated	Low leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate	Value	9.47 X 10-03	Calculated	-
	Note	-
Potential for particle bound transport index		Medium	Calculated	-
Potential for loss via drain flow		Moderately mobile	Calculated	-
Bio-concentration factor	BCF (l kg⁻¹)	33	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	Low potential
	CT₅₀ (days)	Not available		-

Known soil metabolites

Metabolite	Major/Minor fraction	Estimated maximum occurrence fraction	Notes
deethyl ametryne	-	-	-

Known groundwater metabolites

None

Other known metabolites

Metabolite name and reference	Aliases	Formation medium / Rate	Estimated maximum occurrence fraction	Metabolising enzymes
2-methylthio-4-amino-6-isopropylamino-s-triazine (Ref: GS-11354)	-	Plant	-	-
2-methylthio-4,6-diamino-s-triazine (Ref: GS-26831)	-	Plant	-	-
2-methylthio-4-amino-6-ethylamino-s-triazine (Ref: GS-11355)	-	Plant	-	-

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property		Value	Source; quality score; and other information	Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)		1009	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Rat	Moderate
Mammals - Short term dietary NOEL	(mg kg⁻¹)	-	L2 L = Pesticide manuals and hard copy reference books / other sources 2 = Unverified data of unknown source Rat	-
	(ppm diet)	50		-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Birds - Acute LD₅₀ (mg kg⁻¹)		> 5620	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Anas platyrhynchos	Low
Birds - Short term dietary (LC₅₀/LD₅₀)		-	-	-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)		-	-	-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)		166	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	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)	-	-	-
	Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	> 100	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	Low
	Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)	-	-	-
	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 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)		-	-	-
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)		5	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)		0.70	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 Pimephales promelas 35 day	Moderate
Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)		28	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Daphnia magna	Moderate
Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)		0.32	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 LOEC	Moderate
Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)		1.7	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	Moderate
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)		0.01	F2 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 2 = Unverified data of unknown source Lemna perpusilla 7 day	Moderate
Algae - Acute 72 hour EC₅₀, growth (mg l⁻¹)		0.0036	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source Raphidocelis subcapitata	High
Algae - Chronic 96 hour NOEC, growth (mg l⁻¹)		-	-	-
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)		1009	F4 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents (US EPA Databases Related to Pesticide Risk Assessment ) 4 = Verified data Rat	Moderate
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)		2020	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source Rabbit	-
Mammals - Inhalation LC₅₀ (mg l⁻¹)		> 5.03	E3 E = Manufacturers safety data sheets 3 = Unverified data of known source Rat	-
Other Mammal toxicity endpoints		-	-	-
ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)		0.015	L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source	-
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		-	-	-
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		-	-	-

Health issues

Specific human health issues		Carcinogen Genotoxic Endocrine disruptor No data found A3 A = Chromosome aberration (EFSA database) 3 = Negative ; 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 No data found XNo, known not to cause a problem No data found Respiratory tract irritant Skin irritant Skin sensitiser No data found ✓Yes, known to cause a problem No data found Eye irritant Phototoxicant   ✓Yes, known to cause a problem No data found
General human health issues		Slightly toxic

Handling issues

Property	Value and interpretation
General	Not expected to autoignite; Not highly flammable
CLP classification 2013	Health: H302 Environment: H400, H410
WHO Classification	II (Moderately hazardous)
UN Number	-
Waste disposal & packaging	-

TRANSLATIONS

Language	Name
English	ametryn
French	ametryne
German	Ametryn
Danish	ametryn
Italian	ametrina
Spanish	ametrina
Greek	ametryn
Polish	ametryna
Swedish	-
Hungarian	-
Dutch	ametryn

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Record last updated:	13/01/2023
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