Permethrin
Description
A synthetic pyrethroid that was discovered in 1973. Permethrin is most commonly used as an insecticide to repel/kill mosquitos, mites, ticks, flies, bees, chiggers, lice, and spiders. Pyrethrins work by paralyzing the insects on contact. Forms for the insecticide include liquids, powders, dusts, sprays, and plastic ear tags/collars. It is also used in cremes and lotions for the treatment of lice and scabies. While permethrin is a component some tick collars and medication for dogs and livestock, it is highly toxic to cats and some aquatic organisms. Insect repellents that contain permethrin should only be used on fabrics (clothing, sleeping bags, tents, etc.) and not directly on skin. Chemically, pyrethrins break down fairly rapidly at leave no harmful residues.
Synonyms and Related Terms
[(3-phenoxyphenyl)methyl-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate]; Constrain; Nix; Ambush; Eksmin; Talcord; 3-phenoxybenzyl (1RS)-cis-trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate
Risks
- Irritating to skin, nose, throat, lungs, and eyes.
- Highly toxic to cats
- EChemi: SDS
Physical and Chemical Properties
- Soluble in most organic solvents.
- Insoluble in water.
- Stable to light
- Composition = C21H20Cl2O3 (mol. wt. = 391.3 g/mol)
- CAS = 52645-53-1
- Melting Point = 35 C
- Density = 1.190-1.272 g/ml
- Boiling Point = 200 C
Resources and Citations
- National Pesticide Information Center (NPIC): Permethrin Fact Sheet
- Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
- Marie Svoboda, Conservation Survey Index, unpublished, 1997
- The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 7321
- Wikipedia: Permethrin (Accessed Mar. 20, 2006 and July 2023)