Permethrin 656936 225791135 2008-07-15T12:30:25Z Frank 1475157 [[WP:UNDO|Undid]] revision 225787170 by [[Special:Contributions/Ffemtkl|Ffemtkl]] ([[User talk:Ffemtkl|talk]]) {{Chembox new | Name = Permethrin | ImageFile = Permethrin-2D-skeletal.png | ImageSize = 300px | ImageName = Chemical structure of permethrin | IUPACName = 3-Phenoxybenzyl<br /> (1RS)-cis,trans-3-(2,2-dichlorovinyl)<br />-2,2-dimethylcyclopropanecarboxylate<br /> | Section1 = {{Chembox Identifiers | SMILES = c3ccccc3Oc(c2)cccc2COC(=O)<br />C1C(C1(C)C)C=C(Cl)Cl }} | Section2 = {{Chembox Properties | Formula = C<sub>21</sub>H<sub>20</sub>Cl<sub>2</sub>O<sub>3</sub> | MolarMass = 391.28 g/mol | Density = 1.19 g/cm³, solid | Solubility = Insoluble (5.5 x 10<sup>-3</sup> [[Parts per million|ppm]]) | Appearance = colourless crystals | MeltingPt = 34 °C (307 K) | BoilingPt = 200 °C (473 K) }} | Section7 = {{Chembox Hazards | ExternalMSDS = [http://physchem.ox.ac.uk/MSDS/PE/permethrin.html External MSDS] | MainHazards = Irritating to skin and eyes,<br /> damaging to lungs }} | Section8 = {{Chembox Related | Function = [[pyrethroid]]s | OtherFunctn = [[Bifenthrin]]<br />[[Deltamethrin]] | OtherCpds = }} }} '''Permethrin''' is a common [[chemical synthesis|synthetic]] chemical, widely used as an [[insecticide]] and [[acaricide]] and as an [[insect repellent]]. It belongs to the family of synthetic chemicals called [[pyrethroid]]s and functions as a [[neurotoxin]], affecting [[neuron]] [[cell membrane|membrane]]s by prolonging sodium channel activation. It is not known to harm most mammals or birds. It generally has a low mammalian toxicity and is poorly absorbed by skin. ==Uses== In agriculture, permethrin is mainly used on [[cotton]], [[wheat]], [[maize]], and [[alfalfa]] crops, and is also used to kill [[parasite]]s on [[chicken]]s and other [[poultry]]. It is also extensively used in Europe as a timber treatment against wood boring beetle (woodworm). Its use is controversial since, as a [[broad-spectrum]] chemical, it kills indiscriminately; as well as the intended pests, it can harm beneficial insects including [[honey bee]]s, aquatic life,<ref>{{cite journal | author = R. H. Ian | title = Aquatic organisms and pyrethroids | year = 1989 | journal = [[Pesticide Science]] | volume = 27 | issue = 4 | pages = 429–457 | doi = 10.1002/ps.2780270408}}</ref> and small mammals such as [[mouse|mice]]. Permethrin is toxic to cats and many cats die each year after being given flea treatments intended for dogs, or by contact with dogs who have recently been treated with permethrin. Permethrin is also used in healthcare, to eradicate parasites such as [[head lice]] and mites responsible for [[scabies]], and in industrial and domestic settings to control pests such as [[ant]]s and [[termite]]s. Permethrin kills ticks on contact with treated clothing. According to the [[Connecticut Department of Public Health]], it "has low mammalian toxicity, is poorly absorbed through the skin and is rapidly inactivated by the body. Skin reactions have been uncommon."<ref>{{cite web | url = http://www.dph.state.ct.us/BCH/infectiousdise/tickborne/tick.htm#Permethrin | title = Tick Bite Prevention | author = Kirby C. Stafford III | date = Feb 1999 | publisher = Connecticut Department of Public Health}}</ref> Permethrin is used in tropical areas to prevent [[mosquito]]-borne disease such as [[dengue fever]] and [[malaria]]. Mosquito nets used to cover beds may be treated with a solution of permethrin. This increases the effectiveness of the bed net by killing parasitic insects before they are able to find gaps or holes in the net. Malaria kills 1-3 million people per year, and permethrin is believed to have very low if any toxicity in humans. Military personnel training in malaria-endemic areas may be instructed to treat their uniforms with permethrin as well. An application should last several washes. Recently, in [[South Africa]], residues of permethrin were found in breast milk, together with DDT, in an area that experienced [[DDT]] treatment for malaria control, as well as the use of pyrethroids in small-scale agriculture.<ref>{{cite journal | author = H. Bouwman, B. Sereda and H. M. Meinhardt | title = Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa | year = 2006 | journal = [[Environmental Pollution]] | volume = 144 | issue = 3 | pages = 902–917 | doi = 10.1016/j.envpol.2006.02.002}}</ref> ==Products containing permethrin== Products containing 0.5% permethrin: * [[Repel Permanone]] * * [[Permethrin Tick Repellent]] * Bonide Ant Dust (0.25%) *[Bengal]Fogger * Nix 1% shampoo for [[head lice]]. * Rentokil woodworm Killer 1.8% w/w * [[Elimite]] 5% skin cream or generic equivalent for [[scabies]], [[lice]], [[head lice]], [[bird mites]], [[tropical rat mites]], [[bed bugs]], and other [[mites]]. * [[Lyclear]] 5% skin cream or generic equivalent for [[scabies]] and [[crab lice]]. * Most [[flea]] and tick repellant for dogs (Adams, Bio-Spot, K9-Advantix, Cutter) * Dragnet, a pesticide for home use, also contains permethrin. * Raid Ant and Roach killer, another home insecticide contains 0.2% permethrin. * [[Cutter]] Bug Free Backyard contains 2.5% permethrin * [[Flit]] Products containing 12.6% permethrin: * [[Raid (insecticide)|Raid]] fumigator ==Stereochemistry== Permethrin has four [[Stereoisomerism|stereoisomers]] (two [[enantiomer|enantiomeric pairs]]), arising from the two [[stereocenter|stereocentres]] in the [[cyclopropane]] ring. The ''[[trans]]'' enantiomeric pair is known as '''transpermethrin'''. <gallery> Image:Biopermethrin-2D-skeletal.png|<center>''(1R)''-''trans''-acid moiety, known as '''biopermethrin'''</center> Image:(1S)-trans-permethrin.svg|<center>''(1S)''-''trans''-acid moiety</center> Image:Cis-permethrin-A-2D-skeletal.png |<center>one ''cis'' [[enantiomer]]</center> Image:Cis-permethrin-B-2D-skeletal.png |<center>the other ''cis'' enantiomer</center> </gallery> ==Toxicity== Permethrin is extremely toxic to fish. Extreme care must be taken when using products containing permethrin near water sources. Permethrin is also highly toxic to cats.<ref>[http://news.bbc.co.uk/1/low/uk/7088397.stm BBC NEWS | UK | Cats 'killed by flea treatment'<!-- Bot generated title -->]</ref> Flea and tick repellent formulas intended (and labeled) for dogs may contain permethrin and cause feline permethrin toxicosis in cats: specific flea and tick control formulas intended for feline use, such as those containing [[fipronil]], should therefore be used for cats instead. Currently, permethrin is not a known carcinogen, but a few studies have lead the US EPA to classify the substance as a Category C carcinogen: Possible human carcinogen (the data show limited evidence of carcinogenicity in the absence of human data)<ref>[http://www.pested.psu.edu/infocenter/issues/fqpacanctab.pdf]US EPA List of Chemicals Evaluated for Carcinogenic Potential</ref>. Carcinogenic action in nasal mucosal cells for inhalation exposure is suspected due to observed genotoxicity in human tissue samples, and in rat livers the evidence of increased preneoplastic lesions lends concern over oral exposure.<ref>{{cite journal | author = M. Tisch, P. Schmezer, M. Faulde, A. Groh and H. Maier | title = Genotoxicity studies on permethrin, DEET and diazinon in primary human nasal mucosal cells | year = 2002 | journal = [[European Archives of Oto-Rhino-Laryngology]] | volume = 259 | issue = 3 | pages = 150–153 | doi = 10.1007/s004050100406}}</ref><ref>{{cite journal | author = K. Hakoi, R. Cabral, T. Hoshiya, R. Hasegawa, T. Shirai and N. Ito | title = Analysis of carcinogenic activity of some pesticides in a medium-term liver bioassay in the rat | year = 1992 | journal = [[Teratogenesis, Carcinogenesis, and Mutagenesis]] | volume = 12 | issue = 6 | pages = 269–276 | doi = 10.1002/tcm.1770120605}}</ref> ==References== <references/> ==See also== * [[Methoprene]] ==External links== * [http://news.bbc.co.uk/1/hi/health/2881431.stm Pesticide link to Parkinson Disease] * [http://npic.orst.edu/factsheets/permethrin.pdf Permethrin Fact Sheet - National Pesticide Information Center] * [http://npic.orst.edu/hottopic/PermethrinTreatedClothes.pdf Permethrin-treated Clothing Hot Topic - National Pesticide Information Center] * [http://extoxnet.orst.edu/pips/permethr.htm Permethrin Pesticide Information Profile - Extension Toxicology Network] * [http://www.alanwood.net/pesticides/permethrin.html Permethrin chemical data] * [http://www.therossendalefreepress.co.uk/news/s/212/212931_firm_fined_over_irwell_pollution.html Example of permethrin river poisoning (broken link)] <br> {{Human lice}} {{Ectoparasiticides}} [[Category:Insecticides]] [[Category:Antiparasitic agents]] [[Category:Household chemicals]] [[Category:Organochlorides]] [[Category:Phenol ethers]] [[Category:Pyrethroids]] [[de:Permethrin]] [[fr:Perméthrine]] [[it:Permetrina]] [[nl:Permethrin]] [[fi:Permetriini]]