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. These hazard alerts do not take account of usage patterns or exposure, thus do not represent risk.
Environmental fate
Ecotoxicity
Human health
Environmental fate High alert: Drainflow: Mobile
Ecotoxicity High alert: Birds acute ecotoxicity: High; Bees acute contact ecotoxicity: High
Human health High alert: Mammals acute toxicity: High; Acetyl cholinesterase inhibitor; Neurotoxicant
GENERAL INFORMATION
Description
An insecticide and acaricide which provides persistent control of piercing and sucking pests
Example pests controlled
Aphids including wooly apple aphids, citrus aphid, cotton aphid; Spidermites; Thrips
No UK approval for use as a plant protection agent
EC Regulation 1107/2009 (repealing 91/414)
EC Regulation 1107/2009 status
Not approved
Dossier rapporteur/co-rapporteur
Portugal
Date EC 1107/2009 inclusion expires
Expired
EU Candidate for substitution (CfS)
Not applicable
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
Approved for use (✓) under EC 1107/2009 by Mutual Recognition of Authorisation and/or national regulations in the following EEA countries
ISIceland
NONorway
Additional information
Also used in
Australia
Chemical structure
Isomerism
Vamidothion exhibits optical isomerism, meaning it exists as a mixture of chiral isomers. These isomers arise due to the presence of a chiral centre in its molecular structure, specifically within the phosphorothioate backbone linked to a substituted ethylthio group. While both isomers share similar systemic insecticidal and acaricidal activity, studies have shown that the D-form demonstrates higher contact activity, particularly as an acaricide. Commercial formulations of vamidothion typically contain this mixture of optically active isomers.
Chemical subject to PIC regulations; Subject to the provisions of the UK Poisons Act 1972
Relevant Environmental Water Quality Standards
-
Herbicide Resistance Class (HRAC MoA class)
Not applicable
Herbicide Resistance Class (WSSA MoA class)
Not applicable
Insecticide Resistance Class (IRAC MoA class)
1B
Fungicide Resistance Class (FRAC MOA class)
Not applicable
Examples of recorded resistance
-
Physical state
White crystalline needles
Commercial
Property
Value
Availability status
Current
Introduction & key dates
1962, first reported
Example manufacturers & suppliers of products using this active now or historically
Bayer CropScience
Rhone poulenc
Example products using this active
Asystin Z
Kilval
Trucidor
Formulation and application details
Usually supplied as an emulsifiable concentrate
Commercial production
The production of vamidothion involves multiple chemical synthesis steps starting from precursor compounds. Typically, the process begins with the formation of a thiophosphate ester, which is then reacted with an amide derivative to introduce the necessary functional groups. The synthesis includes alkylation and esterification reactions, often involving reagents like dimethyl phosphorochloridothioate and specific alcohols or amines to achieve the final molecular structure. The resulting compound is purified through distillation or crystallisation.
Impact on climate of production and use
Data for the amount of life cycle GHGs produced by vamidothion are not available in the public domain. However, whilst estimates vary, more general data suggests that between 14 and 19 kilograms of CO₂e is emitted per kilogram of insecticide produced.
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C (mg l⁻¹)
4000
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
High
Solubility - In organic solvents at 20 °C (mg l⁻¹)
-
-
-
Melting point (°C)
43
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
-
Boiling point (°C)
-
-
-
Degradation point (°C)
-
-
-
Flashpoint (°C)
-
-
-
Octanol-water partition coefficient at pH 7, 20 °C
P
6.17 X 10-05
Calculated
-
Log P
-4.21
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Low
Fat solubility of residues
Solubility
-
-
-
Data type
-
-
-
Density (g ml⁻¹)
-
-
-
Dissociation constant pKa) at 25 °C
-
-
-
-
Vapour pressure at 20 °C (mPa)
1.00 X 10-10
L2 L = Pesticide manuals and hard copy reference books / other sources 2 = Unverified data of unknown source
Low volatility
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
8.71 X 10-11
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 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)
1.8
K4 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 4 = Verified data
Non-persistent
DT₅₀ (lab at 20 °C)
-
-
-
DT₅₀ (field)
0.2
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Non-persistent
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
Best available data
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
119
K3 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 3 = Unverified data of known source
Persistent
Note
-
Water-sediment DT₅₀ (days)
7
K3 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 3 = Unverified data of known source
Fast
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)
-
W3 W = French database provided by ARVALIS-Institut du Végétal. Dataset no longer available. 3 = Unverified data of known source
Mobile
Koc (mL g⁻¹)
70
Notes and range
-
Freundlich
Kf (mL g⁻¹)
-
-
-
Kfoc (mL g⁻¹)
-
1/n
-
Notes and range
-
pH sensitivity
-
Fate indices
Property
Value
Source; quality score; and other information
Interpretation
GUS leaching potential index
-1.51
Calculated
Low leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
1.05 X 10-04
Calculated
-
Note
-
Potential for particle bound transport index
Low
Calculated
-
Potential for loss via drain flow
Mobile
Calculated
-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk
-
-
-
Bio-concentration factor
BCF (l kg⁻¹)
75
Q2 Q = Miscellaneous data from online sources 2 = Unverified data of unknown source
Estimated
Low potential
CT₅₀ (days)
Not available
-
Known soil metabolites
Metabolite
Major/Minor fraction
Estimated maximum occurrence fraction
Notes
vamidothion sulfoxide sulfonic acid
-
-
-
vamidothion sulfoxide
-
-
-
Known groundwater metabolites
None
Other known metabolites
Metabolite name and reference
Aliases
Formation medium / Rate
Estimated maximum occurrence fraction
vamidothion sulfoxide
-
Rat
-
vamidothion sulfone
-
Intermediary product
-
des-O-methyl vamidothion
-
Plant
-
dimethyl phosphate
-
Plant; Animal; Rat (Urine)
-
monomethylphosphate
-
Animal; Rat (Urine)
-
O,O-dimethyl phosphorothioate
-
Animal
-
ECOTOXICOLOGY
Terrestrial ecotoxicology
Property
Value
Source; quality score; and other information
Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)
> 64
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
High
Mammals - Short term dietary NOEL
(mg kg⁻¹)
-
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
-
(ppm diet)
50
-
Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Birds - Acute LD₅₀ (mg kg⁻¹)
> 35
L2 L = Pesticide manuals and hard copy reference books / other sources 2 = Unverified data of unknown source
Phasianidae
High
Birds - Short term dietary (LC₅₀/LD₅₀)
-
-
-
Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)
-
-
-
Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)
-
-
-
Soil micro-organisms
-
-
-
Collembola
Acute LC₅₀ (mg kg⁻¹)
-
-
-
Chronic NOEC (mg kg⁻¹)
-
-
-
Non-target plants
Vegetative vigour ER₅₀ (g ha⁻¹)
-
-
-
Seedling emergence ER₅₀ (g ha⁻¹)
-
-
-
Honeybees (Apis spp.)
Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
0.56
R4 R = Peer reviewed scientific publications 4 = Verified data
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)
-
-
-
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)
Harmful at dose 300 g ha⁻¹
AA3 AA = IOBC Database on classification of side effects to beneficial organisms, 2005 3 = Unverified data of known source
Chrysoperla carnea
-
Beneficial insects (Parasitic wasps)
-
-
-
Beneficial insects (Predatory mites)
Harmful at dose 300 g ha⁻¹
AA3 AA = IOBC Database on classification of side effects to beneficial organisms, 2005 3 = Unverified data of known source
Typhlodromus pyri
-
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)
K3 K = Research datasets (e.g. Pandora, Demetra; these datasets no longer available). Norman Ecotoxicology database. (click here ) 3 = Unverified data of known source
Unknown species
Low
Algae - Chronic (growth rate, fresh; mg l⁻¹)
-
-
-
Mesocosm study data
NOEAEC mg l⁻¹
-
-
-
NOEAEC mg l⁻¹
-
-
-
Marine bivalves
-
-
-
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)
> 64
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rat
High
Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)
1160
L3 L = Pesticide manuals and hard copy reference books / other sources 3 = Unverified data of known source
Rabbit
-
Mammals - Inhalation LC₅₀ (mg l⁻¹)
1.73
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)
0.008
A5 A = EU regulatory and evaluation data as published by EC, EFSA (RAR, DAR & Conclusion dossiers), EMA (e.g. EU Annex III PIC DGD) (EU - Pesticides database; EFSA Scientific Publications ) 5 = Verified data used for regulatory purposes
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
