Editing Pyrethrin (section)

{{short description|Class of organic chemical compounds with insecticidal properties}}
[[File:Pyrethrin.svg|thumb|[[:en:Skeletal structure|Chemical structure]] of some pyrethrins: pyrethrin I (R=CH<sub>3</sub>), pyrethrin II (R=CO<sub>2</sub>CH<sub>3</sub>)]]

The '''pyrethrins''' are a class of [[organic compound]]s normally derived from ''[[Chrysanthemum cinerariifolium]]'' that have potent [[Insecticide|insecticidal]] activity by targeting the nervous systems of [[insect]]s. Pyrethrin naturally occurs in chrysanthemum flowers and is often considered an [[organic horticulture|organic]] insecticide when it is not combined with [[piperonyl butoxide]] or other synthetic [[agricultural spray adjuvant|adjuvants]].<ref name="xerces.org">Mader, Eric, and Nancy Lee Adamson. "Organic-Approved Pesticides."Organic-Approved Pesticides (n.d.): n. pag. The Xerxes Society. The Xerces Society for Invertebrate Conservation, Oct. 2012. Web. 10 Mar. 2015. <http://www.xerces.org/wp-content/uploads/2009/12/xerces-organic-approved-pesticides-factsheet.pdf {{Webarchive|url=https://web.archive.org/web/20150319214346/http://www.xerces.org/wp-content/uploads/2009/12/xerces-organic-approved-pesticides-factsheet.pdf |date=2015-03-19 }}></ref> Their insecticidal and insect-repellent properties have been known and used for thousands of years.

Pyrethrins are gradually replacing [[organophosphate]]s and [[organochloride]]s as the pesticides of choice as the latter compounds have been shown to have significant and persistent toxic effects to humans. They first appeared on markets in the 1900s and have been continually used since then in products such as bug bombs, building insect sprays, and even to spray animals so that they do not get infectious diseases.<ref>{{Cite web |title=Pyrethrins General Fact Sheet |url=http://npic.orst.edu/factsheets/pyrethrins.html |access-date=2022-09-26 |website=npic.orst.edu}}</ref>