alpha-Cypermethrin

Chemical properties

alpha-cypermethrin is a colorless crystalline solid or viscous yellowish-brown semisolid mass. mild aromatic odor. easily soluble in alcohols, ketones and aromatic hydrocarbon organic solvents, such as cyclohexanone 515g/l, xylene 315g/l, solubility in water 5 ~ 10mg/l (0.01 ~ 0.2mg/l). it is relatively stable under acidic and neutral conditions, easy to hydrolyze under strong alkaline conditions, and has good thermal stability.

The Uses of alpha-Cypermethrin

alpha-Cypermethrin is a synthetic pyrethroid pesticide used in large-scale commercial agricultural applications as well as in consumer products for domestic purposes.

The Uses of alpha-Cypermethrin

insecticide

The Uses of alpha-Cypermethrin

Alpha-cypermethrin is used to control a wide range of insects, especially Lepidoptera, in fruit, vines, vegetables, cereals, beans, beets, cotton, ornamentals and forestry and other crops. It is also used for insect control in public health and for ectoparasite control on animals.

Definition

ChEBI: Cypermethrin is a carboxylic ester resulting from the formal condensation between 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid and the alcoholic hydroxy group of hydroxy(3-phenoxyphenyl)acetonitrile. It has a role as a pyrethroid ester insecticide, a pyrethroid ester acaricide, an agrochemical and a molluscicide. It is an organochlorine compound, a nitrile, an aromatic ether and a cyclopropanecarboxylate ester. It is functionally related to a 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid.

Agricultural Uses

Insecticide: A U.S. EPA restricted Use Pesticide (RUP) (zeta-Cypermethrin only). Used for the control of a wide range of chewing and sucking insects (particularly Lepidotera, Coleoptera, and Hemiptera) in fruit (including citrus), vegetables, vines, cereals, maize, beet, oilseed rape, potatoes, cotton, rice, soya beans, forestry, and other crops. Control of cockroaches, mosquitoes, flies, and other insect pests in public health; and flies in animal houses. Also used as an animal ectoparasiticide.

Trade name

BESTOX®; CONCORD®; DOMINEX®; FASTAC®; FENDONA®; FMC 45497®[C]; NRDC 160®; RENEGADE®; WL-85871® Cypermethrin-s: FURY® (s-isomer); FMC 56701® (s-isomer)

Potential Exposure

alpha-Cypermethrin useds for the control of a wide range of chewing and sucking insects (particularly lepidotera, coleoptera, and hemiptera) in fruit (including citrus), vegetables, vines, cereals, maize, beet, oilseed rape, potatoes, cotton, rice, soya beans, forestry, and other crops. Control of cockroaches, mosquitoes, flies, and other insect pests in public health; and flies in animal houses. Also used as an animal ectoparasiticide. alpha-Cypermethrin only is a United States Environmental Protection Agency Restricted Use Pesticide (RUP).

Metabolic pathway

Alpha-cypermethrin is composed of two of the four cis-cypermethrin isomers (i.e. two of the eight cypermethrin isomers). These are the lRcisaS and 1ScisaR isomers. The fate of alpha-cypermethrin specifically has been reported for soils, rat and human. Metabolite analysis was conducted in enough detail to indicate that the fate of this mixture is very similar to its fate when presented to biological systems as part of cis-cypermethrin. Thus reference can be made to the cypermethrin entry for details. The structure and Scheme numbering used below refers to the cypermethrin entry.

Shipping

UN3349 Pyrethroid pesticide, solid toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous material. UN3352 Pyrethroid pesticide, liquid toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.

Degradation

Alpha-cypermethrin is stable as a solid but it is readily hydrolysed in solution under alkaline conditions. By analogy with cypermethrin, the rate-determining step in dilute solution is nucleophilic attack by OH^-. Half-lives of cis-cypermethrin in river water and sea water at 25 °C were 21 and 24 days, respectively. Major products were 3-(2,2-dichlorovinyl)- 2,2-dimethylcyclopropanecarboxylic acid (2, DCVA), 3-phenoxybenzaldehyde (9, 3PBAl) and a-carbamoyl-3-phenoxybenzyl 3-(2,2- dichlorovinyl)-2,2-dimethylcyclopropanecarboxyltae (the amide 3); minor products were the a-carboxy analogue of 3 (4) and 3-phenoxybenzoic acid (10,3PBA) (see cypermethrin, Schemes la and lb).
Photodecomposition would be expected to be similar to that of cis-cy permethrin.

Incompatibilities

May react violently with strong oxidi- zers, bromine, 90% hydrogen peroxide, phosphorus trichloride, silver powders, or dust. Incompatible with silver compounds. Mixture with some silver compounds forms explosive salts of silver oxalate.

Waste Disposal

Do not discharge into drains or sewers. Burn in incinerator specifically designed for pes- ticide disposal or dispose as a Hazardous waste in a landfill approved and licensed for the disposal of pesticides. Consult with environmental regulatory agencies for guid- ance on acceptable disposal practices. Ultimate disposal of the chemical must consider: the material’s impact on air quality; potential migration in soil or water; effects on ani- mal, aquatic, and plant life; and conformance with environ- mental and public health regulations.