View source for Cypermethrin

{{short description|Chemical compound}}
{{chembox
| Watchedfields  = changed
| verifiedrevid  = 443552837
| Name           = 
| ImageFile      = Alpha-cypermethrin.svg
| ImageFile2     = Cypermethrin 3d model.png
| IUPACName      = [Cyano-(3-phenoxyphenyl)methyl]3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate
| OtherNames     = 
| SystematicName = 
| Section1       = {{Chembox Identifiers
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 1TR49121NP
| InChI = 1/C22H19Cl2NO3/c1-22(2)17(12-19(23)24)20(22)21(26)28-18(13-25)14-7-6-10-16(11-14)27-15-8-4-3-5-9-15/h3-12,17-18,20H,1-2H3
| InChIKey = KAATUXNTWXVJKI-UHFFFAOYAW
| ChEMBL_Ref = {{ebicite|correct|EBI}}
| ChEMBL = 373204
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C22H19Cl2NO3/c1-22(2)17(12-19(23)24)20(22)21(26)28-18(13-25)14-7-6-10-16(11-14)27-15-8-4-3-5-9-15/h3-12,17-18,20H,1-2H3
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = KAATUXNTWXVJKI-UHFFFAOYSA-N
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo=52315-07-8
| PubChem=2912
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 2809
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 4042
| SMILES = Cl/C(Cl)=C/C3C(C(=O)OC(C#N)c2cccc(Oc1ccccc1)c2)C3(C)C
| MeSHName=Cypermethrin
| KEGG_Ref = {{keggcite|correct|kegg}}
| KEGG = D07763
  }}
| Section2       = {{Chembox Properties
| C=22 | H=19 | Cl=2 | N=1 | O=3
| Appearance=
| Density=
| MeltingPt=
| BoilingPt=
| Solubility=
  }}
| Section3       = 
| Section4       = 
| Section5       = 
| Section6       = {{Chembox Pharmacology
| ATCCode_prefix = P03
| ATCCode_suffix = BA02
| ATC_Supplemental = {{ATCvet|P53|AC08}}
}}
| Section7       = {{Chembox Hazards
| GHSPictograms = {{GHS07}}{{GHS08}}{{GHS09}}
| GHSSignalWord = Warning
| HPhrases = {{H-phrases|H302|H332|H335|H373|H410}}
| PPhrases = {{P-phrases|P260|P261|P264|P270|P271|P273|P301+P317|P304+P340|P317|P319|P330|P391|P403+P233|P405|P501}}
}}
}}

{{Expand German|Cypermethrin|date=November 2024}}

'''Cypermethrin''' ('''CP''') is a synthetic [[pyrethroid]] used as an [[insecticide]] in large-scale commercial agricultural applications as well as in consumer products for domestic purposes. It behaves as a fast-acting [[neurotoxin]] in insects. It is easily degraded on [[soil]] and plants but can be effective for weeks when applied to indoor inert surfaces. It is a non-systemic and non-volatile insecticide that acts by contact and ingestion, used in agriculture and in pest control products. Exposure to sunlight, water and oxygen will accelerate its decomposition. Cypermethrin is highly toxic to fish, bees and aquatic insects, according to the National Pesticide Information Center (NPIC) (previously National Pesticides Telecommunication Network) in the USA.<ref>{{Cite web |date=5 Nov 2024 |title=Cypermethrin |url=https://npic.orst.edu/factsheets/cypermethrin.pdf }}</ref> It is found in many household [[ant]] and [[cockroach]] killers, including [[Raid (insecticide)|Raid]], [[Scotts Miracle-Gro Company|Ortho]], [[Henkel North American Consumer Goods#Brands|Combat]], [[ant chalk]], and some variants of [[Baygon]] in [[Southeast Asia]].

==Uses==
Cypermethrin is used in agriculture to control [[ectoparasite]]s which infest cattle, sheep, and poultry.<ref>{{cite web |url=http://www.fao.org/docrep/w4601e/w4601e07.htm |title=Cypermethrin |publisher=FAO}}</ref>

==Human exposure==
Cypermethrin is moderately toxic through skin contact or ingestion. It may cause irritation to the skin and eyes. Symptoms of dermal exposure include numbness, tingling, itching, burning sensation, loss of bladder control, incoordination, seizures and possible death. Excessive exposure can cause nausea, headache, muscle weakness, salivation, shortness of breath and seizures.{{cn|date=July 2025}}

Pyrethroids may adversely affect the central nervous system. Human volunteers given dermal doses of 130{{nbsp}}μg/cm{{sup|2}} on the earlobe experienced local tingling and burning sensations. One man died after eating a meal cooked in a 10% cypermethrin/oil mix that was mistakenly used for cooking oil.<ref>{{Cite book|title=Pesticides and Neurological Diseases|last=Ecobichon|first=Donald J.|publisher=CRC Press|year=1993|isbn=978-0-8493-4361-2|pages=306}}</ref> Shortly after the meal, the victim experienced nausea, prolonged vomiting, stomach pains, and diarrhea which progressed to convulsions, unconsciousness and coma. Other family members exhibited milder symptoms and survived after hospital treatment.

It may cause allergic skin reactions in humans.<ref>{{cite web | url = https://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/cypermet-ext.html | title = Cypermethrin | publisher = Extension Toxicology Network}}</ref>

In humans, cypermethrin is deactivated by enzymatic hydrolysis to several carboxylic acid metabolites, which are eliminated in the urine. Worker exposure to the chemical can be monitored by measurement of the urinary metabolites, while severe overdosage may be confirmed by quantitation of cypermethrin in blood or plasma.<ref>R. Baselt, ''Disposition of Toxic Drugs and Chemicals in Man'', 8th edition, Biomedical Publications, Foster City, CA, 2008, pp. 389-391.</ref>

==Study in animals==
Cypermethrin is very toxic to cats which cannot tolerate the therapeutic doses for dogs.<ref>{{Cite journal|last=Linnett|first=P-J|date=2008-01-01|title=Permethrin toxicosis in cats|journal=Australian Veterinary Journal|language=en|volume=86|issue=1–2|pages=32–35|doi=10.1111/j.1751-0813.2007.00198.x|pmid=18271821|issn=1751-0813}}</ref> This is associated with [[UGT1A6]] deficiency in cats, the enzyme responsible for metabolizing cypermethrin. As a consequence, cypermethrin remains much longer in the cat's organs than in dogs or other mammals and can be fatal in large doses.

In male rats cypermethrin has been shown to exhibit a toxic effect on the [[reproductive system]] by Elbetieha et al. 2001.<ref name="Koureas-et-al-2012">{{cite journal | last1=Koureas | first1=Michalis | last2=Tsakalof | first2=Andreas | last3=Tsatsakis | first3=Aristidis | last4=Hadjichristodoulou | first4=Christos | title=Systematic review of biomonitoring studies to determine the association | journal=Toxicology Letters | publisher=Elsevier | volume=210 | issue=2 | year=2012 | issn=0378-4274 | doi=10.1016/j.toxlet.2011.10.007 | pages=155–168| pmid=22020228 }}</ref> In another result, after 15 days of continual dosing, both [[androgen receptor]] levels and serum [[testosterone]] levels were significantly reduced. These data suggested that cypermethrin can induce impairments of the structure of [[seminiferous tubules]] and [[spermatogenesis]] in male rats at high doses.<ref>{{cite journal |pmid=22147539 |year=2011 |last1=Hu |first1=JX |last2=Li |first2=YF |last3=Li |first3=J |last4=Pan |first4=C |last5=He |first5=Z |last6=Dong |first6=HY |last7=Xu |first7=LC |title=Toxic effects of cypermethrin on the male reproductive system: With emphasis on the androgen receptor |doi=10.1002/jat.1769 |journal=Journal of Applied Toxicology |pages= 576–585|volume=33|issue=7 |s2cid=22178796 }}</ref>

Long-term exposure to cypermethrin during adulthood is found to induce dopaminergic neurodegeneration in rats, and postnatal exposure enhances the susceptibility of animals to dopaminergic neurodegeneration if rechallenged during adulthood.<ref>{{cite journal |pmid=20371137 |year=2012 |last1=Singh |first1=AK |last2=Tiwari |first2=MN |last3=Upadhyay |first3=G |last4=Patel |first4=DK |last5=Singh |first5=D |last6=Prakash |first6=O |last7=Singh |first7=MP |title=Long term exposure to cypermethrin induces nigrostriatal dopaminergic neurodegeneration in adult rats: Postnatal exposure enhances the susceptibility during adulthood |volume=33 |issue=2 |pages=404–15 |doi=10.1016/j.neurobiolaging.2010.02.018 |journal=Neurobiology of Aging|s2cid=207158692 }}</ref>

If exposed to cypermethrin during pregnancy, rats give birth to offspring with developmental delays. In male rats exposed to cypermethrin, the proportion of abnormal sperm increases. It causes genetic damage: chromosomal abnormalities increased in bone marrow and spleen cells when mice were exposed to cypermethrin.<ref>{{cite journal|year=1993|title=Induction of chromosomal aberrations and sister chromatid exchange in vivo and in vitro by the insecticide cypermethrin| journal= Journal of Applied Toxicology | volume = 13 | pages = 341–345| author=Amer, S.M.|doi=10.1002/jat.2550130508|pmid=8258631|issue=5|s2cid=41816737|display-authors=etal}}</ref> Cypermethrin is classified as a possible human [[carcinogen]], because it causes an increase in the frequency of lung tumors in female mice. Cypermethrin has been linked to an increase in bone marrow [[micronuclei]] in both mice and humans.<ref>{{cite journal|year=1985|title=Cytogenetic effects of pesticides. III. Induction of micronuclei in mouse bone marrow by the insecticides cypermethrin and rotenone| journal= Journal of Mutation Research |volume = 155 | pages = 135–142|author1=Amer, S.M.  |author2=E.I. Aboulela|doi=10.1016/0165-1218(85)90132-6|pmid=3974628|issue=3}}</ref>
 
One study showed that cypermethrin inhibits “gap junctional intercellular communication”, which plays an important role in cell growth and is inhibited by carcinogenic agents.<ref>{{cite journal|year=1993|title=Effects of pyrethroid insecticides on gap junctional intecellular communications in Balb/c3T3 cells by dye-transfer assay | journal=Cell Biology and Toxicology | volume = 9 | pages = 215–222| author=Tateno, C.|doi=10.1007/BF00755600|pmid=8299001 |last2=Ito|first2=Seiichi|last3=Tanaka|first3=Mina|last4=Yoshitake|first4=Akira|issue=3|s2cid=10055706 |display-authors=etal}}</ref> Studies have shown that residue from cypermethrin can last for 84 days in the air, on walls, the floor and on furniture.<ref>{{cite journal|year=1993|title=Cypermethrin in the ambient air and on surfaces of rooms treated for cockroaches| journal=Bulletin of Environmental Contamination and Toxicology | volume = 51 | pages = 356–360|author1=Wright, C.G. |author2=R.B. Leidy |author3=H.E. Dupree Jr.  |name-list-style=amp |doi=10.1007/BF00201752|pmid=8219589|issue=3|bibcode=1993BuECT..51..356W |s2cid=37107396}}</ref>

==Environmental effects==
Cypermethrin is a broad-spectrum insecticide, which means it kills beneficial insects as well as the targeted insects.<ref>{{cite journal|year=1992|title=Effects of forest spraying with two application rates of cypermethrin on food supply and on breeding success of the blue tit (Parus caeruleus)| journal=Environmental Toxicology and Chemistry | volume = 11 | issue = 9 | pages = 1271–1280|author1=Pascual, J.A.  |author2=S.J. Peris | doi = 10.1002/etc.5620110907|bibcode=1992EnvTC..11.1271P }}</ref> Fish are particularly susceptible to cypermethrin,<ref>{{cite journal|year=1982|title=Aquatic toxicology of cypermethrin. I. Acute toxicity to some freshwater fish and invertebrates in laboratory tests| journal=Aquatic Toxicology | volume = 2 | issue = 3 | pages = 175–185 | author=Stephenson, R.R.|doi=10.1016/0166-445X(82)90014-5|bibcode=1982AqTox...2..175S }}</ref><ref>{{Cite journal|last1=Ranjani|first1=T. Sri|last2=Pitchika|first2=Gopi Krishna|last3=Yedukondalu|first3=K.|last4=Gunavathi|first4=Y.|last5=Daveedu|first5=T.|last6=Sainath|first6=S. B.|last7=Philip|first7=G. H.|last8=Pradeepkiran|first8=Jangampalli Adi|date=2020-02-07|title=Phenotypic and transcriptomic changes in zebrafish (Danio rerio) embryos/larvae following cypermethrin exposure|journal=Chemosphere|volume=249|article-number=126148|doi=10.1016/j.chemosphere.2020.126148|issn=1879-1298|pmid=32062212|bibcode=2020Chmsp.24926148R|s2cid=211134591}}</ref> but when used as directed, application around residential sites poses little risk to aquatic life.<ref name=npic>{{cite web | url = http://npic.orst.edu/factsheets/cypermethrin.pdf | title = Cypermethrin | publisher = National Pesticide Information Center}}</ref> Resistance to cypermethrin has developed quickly in insects exposed frequently and can render it ineffective.<ref>{{cite journal|year=1991|title=Responses of populations of the tobacco budworm (Lepidopterea: Noctuidae) from northwest Mexico to pyrethroids | journal=Journal of Economic Entomology | volume = 84 | issue = 2 | pages = 363–366 | author=Martinez-Cabrillo, J.L.|display-authors=etal|doi=10.1093/jee/84.2.363 }}</ref>

==References==
{{reflist|2}}

==External links==
* [http://npic.orst.edu/factsheets/cypermethrin.pdf Cypermethrin Fact Sheet - National Pesticide Information Center]
* [http://extoxnet.orst.edu/pips/cypermet.htm Cypermethrin Pesticide Information Profile - Extension Toxicology Network]
* {{PPDB|197|Name=cypermethrin}}
* {{PPDB|24|Name=alpha-cypermethrin}}
* {{PPDB|682|Name=zeta-cypermethrin}}

{{Insecticides}}
{{Xenobiotic-sensing receptor modulators}}

[[Category:Neurotoxins]]
[[Category:Organochlorides]]
[[Category:Endocrine disruptors]]
[[Category:(cyano-(3-phenoxyphenyl)methyl) 2,2,3-trimethylcyclopropane-1-carboxylates]]
[[Category:Pyrethroids]]