Azamethiphos is an

organothiophosphate Organothiophosphates or organophosphorothioates are a subclass of organophosphorus compounds. Many are used as pesticides, some have medical applications, and some are used as oil additives. They generally have the chemical formula (RO)3PS, RO)2 ...

insecticide Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to b ...

. It is a

veterinary drug An animal drug (also veterinary drug) refers to a pharmaceutical drug, drug intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in animals. Regulation United States The U.S. Food and Drug Administration (FDA) ...

used in

Atlantic salmon The Atlantic salmon (''Salmo salar'') is a species of ray-finned fish in the family Salmonidae. It is the third largest of the Salmonidae, behind Siberian taimen and Pacific Chinook salmon, growing up to a meter in length. Atlantic salmon are ...

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ing to control parasites. It is also used as an insecticide in biocidal products in Europe.

Mode of action

Organophosphorus insecticides, such as Azamethiphos, inhibit the action of the enzyme

acetylcholinesterase Acetylcholinesterase (HGNC symbol ACHE; EC 3.1.1.7; systematic name acetylcholine acetylhydrolase), also known as AChE, AChase or acetylhydrolase, is the primary cholinesterase in the body. It is an enzyme Enzymes () are proteins that a ...

. The acetylcholine, therefore, remains intact allowing the electrical signal to proceed without interruption. This phenomenon leads to overexcitation of the organism and eventually to the death of the insect. Armosa factsheet on Azamethiphos, February 2022 Azamethiphos penetrates through the cuticle or through the cuticle opening of the insect, and also acts by ingestion and absorption through the digestive system.

Registration

In Europe, Azamethiphos is an active substance according to the Biocide Regulation 528/2012, to be used as insecticide. It is used in several biocidal products in Europe, as insecticide mainly for professional users. It is commonly used against flies in animal housing.

Stability

Azamethiphos is sensitive to hydrolysis, especially at low pH.

Toxicity

Azamethiphos is of moderate acute oral toxicity (LD50 values ranging from 834 mg kg-1 in the rat to 1764 mg kg-1 in the hamster). Acute dermal toxicity is very low (LD50 values of >2020 and >6000 mg kg-1 are reported in the rabbit and an LD50 of >2150 mg kg-1 is reported in the rat). Azamethiphos is irritant to eyes and skin.

Environmental toxicity

Azamethiphos is very toxic for the environment, with a LC50 on ''Daphnia magna'' of 0.33 µg/L.

References

Organothiophosphate esters Insecticides Veterinary drugs {{antiinfective-drug-stub