(Also known as: ethyl dipropylthiocarbamate; epthame; eptam)
SUMMARY
EPTC is a selective herbicide. It is moderately soluble in water and is highly volatile. It is not expected to be persistent in soil systems but may be in water depending on local conditions. There may be a risk of drift. EPTC is moderately toxic to most biodiversity. This substance is also moderately toxic to mammals via the oral route. EPTC is an acetyl cholinesterase inhibitor, a neurotoxin and an irritant.
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: GUS: Transition state; Drainflow: Moderately mobile
Selective, systemic absorbed by roots and shoots. Lipid synthesis inhibitor.
CAS RN
759-94-4
EC number
212-073-8
CIPAC number
155
US EPA chemical code
041401
PubChem CID
12968
CLP index number
006-030-00-0
Molecular mass
189.3
PIN (Preferred Identification Name)
S-ethyl dipropylcarbamothioate
IUPAC name
S-ethyl dipropyl(thiocarbamate)
CAS name
S-ethyl dipropylcarbamothioate
Other status information
Potential groundwater contaminant; PAN listed Highly Hazardous Chemical; Risk of drift.
Relevant Environmental Water Quality Standards
-
Herbicide Resistance Class (HRAC MoA class)
K3
Herbicide Resistance Class (WSSA MoA class)
15
Insecticide Resistance Class (IRAC MoA class)
Not applicable
Fungicide Resistance Class (FRAC MOA class)
Not applicable
Examples of recorded resistance
-
Physical state
Pale yellow liquid
Formulations
Property
Value
Example manufacturers & suppliers of products using this active now or historically
Stauffer
Example products using this active
Eradicane
Eptam
Genep
Shortstop
Formulation and application details
Usually formulated as an emulsifiable concentrate or as granules
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
370
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Moderate
Solubility - In organic solvents at 20 °C (mg l⁻¹)
Miscible
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Acetone
-
Miscible
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Benzene
-
Miscible
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Xylene
-
Miscible
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Ethanol
-
Melting point (°C)
Not applicable
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Boiling point (°C)
127
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Degradation point (°C)
200
L2 L = Pesticide manuals and hard copy reference books / other sources 2 = Unverified data of unknown source
-
Flashpoint (°C)
110
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
1.58 X 1003
Calculated
-
Log P
3.2
G4 G = Extension Toxicology network database EXTOXNET. Available online but no longer updated. (click here ) 4 = Verified data
High
Fat solubility of residues
Solubility
-
-
-
Data type
-
-
-
Density (g ml⁻¹)
0.96
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Dissociation constant pKa) at 25 °C
Not applicable
Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source
-
No dissociation
Vapour pressure at 20 °C (mPa)
4500
G3 G = Extension Toxicology network database EXTOXNET. Available online but no longer updated. (click here ) 3 = Unverified data of known source
Highly volatile. If applied directly to plants or soil, drift is a concern & mitigation is advisable
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
5.00 X 10-06
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
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)
6
M3 M = GLEAMS Model database (Groundwater Loading Effects of Agricultural Management Systems). Dataset no longer available. 3 = Unverified data of known source
Non-persistent
DT₅₀ (lab at 20 °C)
-
-
-
DT₅₀ (field)
18
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Non-persistent
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
Literature DT₅₀ range 6-30 days in the field; Other sources: DT₅₀ 30-60 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
-
-
-
Note
-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7
Value
300
C4 C = AGRITOX dataset. Dataset is no longer available. 4 = Verified data
Persistent
Note
-
Water-sediment DT₅₀ (days)
-
-
-
Water phase only DT₅₀ (days)
-
-
-
Sediment 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)
-
G3 G = Extension Toxicology network database EXTOXNET. Available online but no longer updated. (click here ) 3 = Unverified data of known source
Moderately mobile
Koc (mL g⁻¹)
300
Notes and range
Other literature sources: 109-240 mL g⁻¹ (R3)
Freundlich
Kf (mL g⁻¹)
0.76
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
Moderately mobile
Kfoc (mL g⁻¹)
187.7
1/n
0.905
Notes and range
Literature data: Kf range 0.36-0.47 mL g⁻¹, Kfoc range 153-222 mL g⁻¹, 1/n range 0.826-0.984, soils=2
pH sensitivity
-
Fate indices
Property
Value
Source; quality score; and other information
Interpretation
GUS leaching potential index
2.17
Calculated
Transition state
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
7.50 X 10-02
Calculated
-
Note
-
Potential for particle bound transport index
Low
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)
60
P4 P = Other non-EU, UK or US Governments and Regulators 4 = Verified data
Low potential
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)
916
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
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 21 day
-
(ppm diet)
326
-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Birds - Acute LD₅₀ (mg kg⁻¹)
1000
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
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)
267
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)
11.0
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Moderate
Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
-
-
-
Chronic
-
-
-
Notes
-
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)
14
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Lepomis macrochirus
Moderate
Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)
-
-
-
Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
Aquatic plants - Acute 7 day EC₅₀, biomass (mg l⁻¹)
2.9
F1 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 ) 1 = Estimated data with little or no verification
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
Environmental fate
Human health
