Editing Ethanol (section)

== Natural occurrence ==
Ethanol is a byproduct of the metabolic process of yeast. As such, ethanol will be present in any yeast habitat. Ethanol can commonly be found in overripe fruit.<ref>{{cite journal | vauthors=Dudley R | title=Ethanol, fruit ripening, and the historical origins of human alcoholism in primate frugivory | journal=Integrative and Comparative Biology | volume=44 | issue=4 | pages=315–323 | date=August 2004 | pmid=21676715 | doi=10.1093/icb/44.4.315 | doi-access=free}}</ref> Ethanol produced by symbiotic yeast can be found in [[palm wine|bertam palm]] blossoms. Although some animal species, such as the [[pentailed treeshrew]], exhibit ethanol-seeking behaviors, most show no interest or avoidance of food sources containing ethanol.<ref>{{cite web | title=Fact or Fiction?: Animals Like to Get Drunk | last=Graber | first=Cynthia | name-list-style=vanc | year=2008 | url=http://www.scientificamerican.com/article.cfm?id=animals-like-to-get-drunk | website=Scientific American | access-date=23 July 2010}}</ref> Ethanol is also produced during the germination of many plants as a result of natural [[anaerobiosis]].<ref>{{cite journal | doi=10.1007/BF02922229 | last1=Leblová | first1=Sylva | last2=Sinecká | first2=Eva | last3=Vaníčková | first3=Věra | name-list-style=vanc | title=Pyruvate metabolism in germinating seeds during natural anaerobiosis | year=1974 | journal=Biologia Plantarum | volume=16 | issue=6 | pages=406–411 | bibcode=1974BioPl..16..406L | s2cid=34605254}}</ref>

Ethanol has been detected in [[outer space]], forming an icy coating around dust grains in [[interstellar cloud]]s.<ref>{{cite journal | doi=10.1016/j.chemphys.2007.02.018 | title=One possible origin of ethanol in interstellar medium: Photochemistry of mixed CO<sub>2</sub>–C<sub>2</sub>H<sub>6</sub> films at 11 K. A FTIR study | vauthors=Schriver A, Schriver-Mazzuoli L, Ehrenfreund P, d'Hendecourt L | journal=Chemical Physics | volume=334 | issue=1–3 | year=2007 | pages=128–137 | bibcode=2007CP....334..128S}}</ref>
Minute quantity amounts (average 196 [[parts per billion|ppb]]) of endogenous ethanol and acetaldehyde were found in the exhaled breath of healthy volunteers.<ref>{{cite journal | vauthors=Turner C, Spanel P, Smith D | title=A longitudinal study of ethanol and acetaldehyde in the exhaled breath of healthy volunteers using selected-ion flow-tube mass spectrometry | journal=Rapid Communications in Mass Spectrometry | volume=20 | issue=1 | pages=61–68 | year=2006 | pmid=16312013 | doi=10.1002/rcm.2275 | bibcode=2006RCMS...20...61T}}</ref> [[Auto-brewery syndrome]], also known as gut fermentation syndrome, is a rare medical condition in which intoxicating quantities of ethanol are produced through [[endogenous]] [[fermentation]] within the [[digestive system]].<ref>{{cite web | url=https://www.npr.org/blogs/thesalt/2013/09/17/223345977/auto-brewery-syndrome-apparently-you-can-make-beer-in-your-gut | title=Auto-Brewery Syndrome: Apparently, You Can Make Beer In Your Gut | first=Michaeleen | last=Doucleff | name-list-style=vanc | publisher=NPR | date=17 September 2013}}</ref>