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 persistent 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, honeybees 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
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. Dataset is no longer available. 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. Dataset is no longer available. 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. Dataset is no longer available. 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. If applied directly to plants, drift is a concern & mitigation is advisable
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
4.10 X 10-04
H4 H = The US ARS pesticide properties database. Dataset is no longer available. 4 = Verified data
Non-volatile
Volatilisation as max % of applied dose lost
From plant surface
-
-
-
From soil surface
-
-
-
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. Dataset is no longer available. 4 = Verified data
Moderately persistent
DT₅₀ (lab at 20 °C)
60
Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source
Moderately persistent
DT₅₀ (field)
37
H4 H = The US ARS pesticide properties database. Dataset is no longer available. 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 (days) on plant matrix
Value
-
-
-
Note
-
Dissipation rate RL₅₀ (days) 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. Dataset no longer available. 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. Dataset no longer available. 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)
-
-
-
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
Kd (mL g⁻¹)
-
H3 H = The US ARS pesticide properties database. Dataset is no longer available. 3 = Unverified data of known source
Moderately mobile
Koc (mL g⁻¹)
316
Notes and range
General literature Koc range 170-390 mL g⁻¹
Freundlich
Kf (mL g⁻¹)
76.81
R4 R = Peer reviewed scientific publications 4 = Verified data
Non-mobile
Kfoc (mL g⁻¹)
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
-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk
-
-
-
Bio-concentration factor
BCF (l kg⁻¹)
33
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
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
Temperate Freshwater 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
Temperate Freshwater 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 / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
Pimephales promelas 35 day
Moderate
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
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 / FAO data, IPCS INCHEM data (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
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