View source for Chemistry:Allethrins

{{short description|Class of synthetic chemicals used as insecticides}}
[[Image:Allethrin 2D.svg|thumb|right|300px|Allethrin I (R = −CH<sub>3</sub>)<br>Allethrin II (R = −COOCH<sub>3</sub>)]]
The '''allethrins''' are a group of related synthetic compounds used in insecticides. They are classified as [[Chemistry:Pyrethroid|pyrethroid]]s, i.e. synthetic versions of [[Biology:Pyrethrin|pyrethrin]], a chemical with insecticidal properties found naturally in ''[[Biology:Chrysanthemum|Chrysanthemum]]'' flowers. They were first synthesized in the United States by Milton S. Schechter in 1949. Allethrin was the first [[Chemistry:Pyrethroid|pyrethroid]].

They are commonly used in [[Biology:Ultra-low volume|ultra-low volume]] sprays for outdoor [[Biology:Mosquito|mosquito]] control, and in many household insecticides such as RAID, as well as [[Chemistry:Mosquito coil|mosquito coil]]s.

==Chemical structure==
Allethrin I and allethrin II differ by having a [[Chemistry:Methyl group|methyl group]] and a methyl ester, respectively, on one terminus.  Each of these allethrins consists of the eight possible stereoisomers. A partly enantiopure variant of allethrin I, consisting of only two stereoisomers in an approximate ratio of 1:1, is called [[Chemistry:Bioallethrin|bioallethrin]]. The same mixture of isomers, but in an approximate ratio of 3:1, is known as esbiothrin.

==Toxicity==
Chronic exposure to allethrins alters the plasma biochemical profile of humans and may have adverse health effects.<ref>{{cite journal |last1=Narendra |first1=M. |last2=Kavitha |first2=G. |last3=Helah Kiranmai |first3=A. |last4=Raghava Rao |first4=N. |last5=Varadacharyulu |first5=N.C. |title=Chronic exposure to pyrethroid-based allethrin and prallethrin mosquito repellents alters plasma biochemical profile |journal=Chemosphere |date=September 2008 |volume=73 |issue=3 |pages=360–364 |doi=10.1016/j.chemosphere.2008.05.070|pmid=18657844 |bibcode=2008Chmsp..73..360N }}</ref> [[Chemistry:Bioallethrin|Bioallethrin]] has been shown to cause oxidative damage, cellular toxicity and necrosis of human lymphocytes studied in vitro.<ref>{{cite journal |last1=Arif |first1=Amin |last2=Quds |first2=Ruhul |last3=Mahmood |first3=Riaz |title=Bioallethrin enhances generation of ROS, damages DNA, impairs the redox system and causes mitochondrial dysfunction in human lymphocytes |journal=Scientific Reports |date=December 2021 |volume=11 |issue=1 |pages=8300 |doi=10.1038/s41598-021-87799-3|pmid=33859309 |pmc=8050322  }}</ref> It is highly toxic to fish and aquatic invertebrates. At normal application rates, allethrin is slightly toxic to bees.<ref>{{cite web | url = http://pmep.cce.cornell.edu/profiles/extoxnet/24d-captan/allethrin-ext.html#5 | title = Pesticide Information Profile - Allethrin | publisher = pmep.cce.cornell.edu}}</ref> Insects subject to exposure become paralyzed (nervous system effect) before dying. Allethrins are toxic to cats<ref>{{cite web | url = http://www.peteducation.com/article.cfm?c=2+1677&aid=2252 | title = Pyrethrin and Permethrin Toxicity in Dogs and Cats | publisher = peteducation.com | access-date = 2013-05-12 | archive-url = https://www.webcitation.org/6Gst21cUu?url=http://www.peteducation.com/article.cfm?c=2+1677 | archive-date = 2013-05-25 | url-status = dead }}</ref> because they either do not produce, or produce less of certain isoforms of [[Biology:Glucuronosyltransferase|glucuronosyltransferase]], which serve in hepatic detoxifying metabolism pathways.<ref>{{Cite journal | last1 = Court | first1 = M. H. | last2 = Greenblatt | first2 = D. J. | title = Molecular genetic basis for deficient acetaminophen glucuronidation by cats: UGT1A6 is a pseudogene, and evidence for reduced diversity of expressed hepatic UGT1A isoforms | journal = Pharmacogenetics | volume = 10 | issue = 4 | pages = 355–369 | year = 2000 | pmid = 10862526 | doi=10.1097/00008571-200006000-00009}}</ref>

==Notes==
{{reflist}}

==References==
*Oregon State University (1996). [http://extoxnet.orst.edu/pips/allethri.htm Allethrin]. Retrieved October 26, 2005.
*Illinois Department of Public Health  [http://www.idph.state.il.us/envhealth/factsheets/pyrethroid.htm Pyrethroid Insecticides Fact Sheet]. Retrieved October 26, 2005.
*[[Organization:World Health Organization|World Health Organization]] (WHO)  [http://webarchive.loc.gov/all/20041227231112/http://www.who.int/whopes/quality/en/dAllethrin_spec_eval_March_04.pdf d-Allethrin]. Retrieved October 26, 2005.
*Jim E. Riviere & Mark G. Papich Eds.: Veterinary Pharmacology and Therapeutics. Iowa State University Press, 2009. {{ISBN|9780813820613}}. (p.&nbsp;1194)

==External links==
*[http://npic.orst.edu/factsheets/pyrethrins.pdf Pyrethrins and Pyrethroids Fact Sheet - National Pesticide Information Center]
*[http://extoxnet.orst.edu/pips/allethri.htm Allethrin Pesticide Information Profile - Extension Toxicology Network]

{{insecticides}}

[[Category:Pyrethroids]]
[[Category:Enones]]
[[Category:Cyclopentenes]]

{{Sourceattribution|Allethrins}}