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Further data may be found in the PPDB
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
for azamethiphos
Description:
Used in fish farming to control external parasites on Atlantic Salmon and for parasite control on other animals
Availability status:
Current
Introduction & key dates:
1970
Examples of species treated:
Salmon; Dogs; cats
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:
Veterinary substance type |
Antiparasitic |
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. |
Molecular targets |
Cholinesterase, inhibitor |
CAS RN |
35575-96-3 |
EC number |
252-626-0 |
CIPAC number |
8022 |
US EPA chemical code |
- |
PubChem CID |
71482 |
ATCvet Code |
QP53AF17 |
Therapeutic Class |
Antiparasitic products, insecticides & repellents: Ecoparasiticides, insecticides & repellents |
Controlled Drug? |
No |
Regulation 37/2010 MRL Classification |
Allowed substance (Table 1: Salmonidae) |
Molecular mass (g mol-1) |
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 ug/L as annual average, 0.05 as max acceptable conc. |
Physical state |
Colourless to grey cystalline solid |
Related substances & organisms |
- |
Formulations:
Property  |
Product |
Manufacturer |
Authorisation Route |
UK Legal Class |
Example products using this active |
Salmosan Powder for Suspension for Fish Treatment |
Fish Vet Group |
UK National authorisation |
Prescription only medicine to be authorised by a veterinarian (POM-V) |
Formulation and application details |
Often supplied as a wettable powders, direct use bait formulations and as bath additives. |
ENVIRONMENTAL FATE
for azamethiphos
Property  |
Value |
Source/Quality Score/Other Information  |
Interpretation  |
Solubility - In water at 20oC (mg l-1) |
1100 |
E3 |
High |
Solubility - In organic solvents at 20oC (mg l-1) |
610000 |
L3 - Dichloromethane |
- |
130000 |
L3 - Benzene |
- |
100000 |
L3 - Methanol |
- |
5800 |
L3 - n-Octanol |
- |
Melting point (oC) |
89 |
L3 |
- |
Boiling point (oC) |
Decomposes before boiling |
Q3 |
- |
Degradation point (oC) |
- |
- |
- |
Flashpoint (oC) |
150 |
L3 |
- |
Octanol-water partition coefficient at pH 7, 20oC |
P |
1.12 X 1001 |
Calculated |
- |
Log P |
1.05 |
L3 |
Low |
Bulk density (g ml-1)/Specific gravity |
1.6 |
L3 |
- |
Dissociation constant (pKa) at 25oC |
- |
- |
- |
Note: |
Vapour pressure at 20oC (mPa) |
0.0049 |
E3 |
Low volatility |
Henry's law constant at 25oC (Pa m3 mol-1) |
1.45 X 10-06 |
L3 |
Non-volatile |
GUS leaching potential index  |
-1.57 |
Calculated |
Low leachability |
Maximum UV-vis absorption L mol-1 cm-1 |
- |
- |
- |
Surface tension (mN m-1) |
- |
- |
- |
Refractive Index |
- |
- |
- |
Degradation:
Property  |
Value |
Source/Quality Score/Other Information  |
Interpretation  |
Soil degradation (days) (aerobic) |
DT50 (typical) |
0.25  |
L3 |
Non-persistent |
DT50 (lab at 20oC) |
- |
- |
- |
DT50 (field) |
- |
- |
- |
DT90 (lab at 20oC) |
- |
- |
- |
DT90 (field) |
- |
- |
- |
Note |
Best available data, Industry data DT50 in loamy sand circa 6 hours (E3) |
Manure DT50 (days) |
- |
- |
- |
Aqueous photolysis DT50 (days) at pH 7 |
Value |
- |
- |
- |
Note |
- |
Aqueous hydrolysis DT50 (days) at 20oC and pH 7 |
Value |
11 |
L3 |
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/Other Information  |
Interpretation  |
Linear
| Kd |
- |
S1 |
Mobile |
Koc |
25 |
Notes and range |
Estimated |
Freundlich
| Kf |
- |
- |
- |
Kfoc |
- |
1/n |
- |
Notes and range |
- |
pH sensitivity |
- |
ECOTOXICOLOGY
for azamethiphos
Property  |
Value |
Source/Quality Score/Other Information  |
Interpretation  |
Bio-concentration factor |
BCF (l kg-1) |
1.56 |
Q2 Estimated |
Low potential |
CT50 (days) |
Not available |
- |
Mammals - Acute oral LD50 (mg kg-1) |
1180 |
L3 Rat |
Moderate |
Mammals - Short term dietary NOEL |
(mg kg-1) |
2 |
L3 Rat |
High |
(ppm diet) |
20 |
- |
Birds - Acute LD50 (mg kg-1) |
> 30.2 |
L3 Colinus virginianus |
High |
Birds - Short term dietary (LC50/LD50) |
- |
- |
- |
Fish - Acute 96 hour LC50 (mg l-1) |
> 0.115 |
L3 Oncorhynchus mykiss |
Moderate |
Fish - Chronic 21 day NOEC (mg l-1) |
- |
- |
- |
Aquatic invertebrates - Acute 48 hour EC50 (mg l-1) |
0.00067 |
L3 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 |
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
for azamethiphos
General:
Property  |
Value |
Source/Quality Score/Other Information  |
Interpretation  |
Threshold of Toxicological Concern (Cramer Class)  |
High (class III) |
- |
- |
Mammals - Acute oral LD50 (mg kg-1) |
1180 |
L3 Rat |
Moderate |
Mammals - Dermal LD50 (mg kg-1 body weight) |
> 2150 |
L3 Rat |
- |
Mammals - Inhalation LC50 (mg l-1) |
> 0.56 |
L3 Rat |
- |
Other Mammal toxicity endpoints |
- |
|
- |
ADI - Acceptable Daily Intake (mg kg-1bw day-1) |
0.003 |
UK ACP 2001 |
- |
ARfD - Acute Reference Dose (mg kg-1bw day-1) |
0.01 |
UK ACP 2001 |
- |
AAOEL - Acute Acceptable Operator Exposure Level (mg kg-1 bw day-1) |
- |
- |
- |
AOEL - Acceptable Operator Exposure Level - Systemic (mg kg-1bw day-1) |
0.1 |
UK ACP 2001 ST |
- |
Dermal penetration studies (%) |
- |
- |
- |
Dangerous Substances Directive 76/464 |
List I; List II |
- |
- |
Exposure Routes |
Public |
- |
Occupational |
- |
Elimination route and rate |
For rats azamethiphos is excreted via faeces, urine & in expelled air. For fish adsorption after topical application is slow and low. Excretion is rapid in all species. |
A4 |
- |
Health issues:
Carcinogen |
Genotoxic |
Endocrine disrupter |
Reproduction / development effects |
Cholinesterase inhibitor |
Neurotoxicant |
- |
A3; B3; C3; D0; E1 |

|
- |

|

|
Respiratory tract irritant |
Skin irritant |
Skin sensitiser |
Eye irritant |
Phototoxicant |
|
- |

|

|

|
- |
|
General human health issues |
Mutagenic potential |
Key: Genotoxicity A: Chromosome aberration (EFSA database) B: DNA damage/repair (EFSA database) C: Gene mutation (EFSA database) D: Genome mutation (EFSA database) E: Unspecified genotoxicity type (miscellaneous data source) 0: No data 1: Positive 2: Mixed/ambiguous results 3: Negative |
Key: Other
: Yes, known to cause a problem
: No, known not to cause a problem
: Possibly, status not identified - : No data found |
Handling issues:
Property  |
Value |
Source/Quality Score/Other Information  |
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
for azamethiphos
Language |
Name |
English |
azamethiphos |
French |
azametiphos |
German |
Azamethiphos |
Danish |
azamethiphos |
Italian |
azametifos |
Spanish |
azametifos |
Greek |
- |
Slovenian |
azametifos |
Polish |
azametifos |
Swedish |
azametifos |
Hungarian |
- |
Dutch |
azamethifos |
Record last updated: Tuesday 26 November 2019
Contact: aeru@herts.ac.uk