View source for Engineering:Sponge (tool)

{{short description|Cleaning tool made up of porous material}}
[[File:Éponge type 3 (1).jpg|thumb|Vegetable fiber sponge: [[Chemistry:Wood fibre|wood fiber]] sponge combined with scouring pad.]]
[[File:Schwamm1.jpg|thumb|Animal fiber sponge: A Greek natural sponge.]]

A '''sponge''' ({{IPAc-en|'|s|p|ʌ|n|dʒ}} {{Respell|SPUNJ}}) is a cleaning aid made of soft, porous material. Typically used for cleaning impervious surfaces, sponges are especially good at [[Physics:Capillary action|absorbing]] water and water-based solutions.

Originally made from natural [[Biology:Sponge|sea sponges]], they are most commonly made from synthetic materials today.

== Etymology ==
The word comes from the [[Social:Ancient Greek|Ancient Greek]] term {{wikt-lang|grc|σπόγγος}} ({{grc-transl|σπόγγος}}),<ref>{{cite web|url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aalphabetic+letter%3D*s111%3Aentry+group%3D61%3Aentry%3Dspo%2Fggos|title=Henry George Liddell, Robert Scott, A Greek-English Lexicon }}</ref> which in turn is probably derived from a Mediterranean [[Social:Pre-Indo-European languages|Pre-Indo European substrate]].

== History ==
The first reference of sponges used for hygiene dates from {{wipe|Ancient Greece}}. Competitors of the [[Social:Ancient Olympic Games|Olympic Games]] bathed themselves with sea sponges soaked in olive oil or perfume before competing. In the book ''[[Religion:Odyssey|Odyssey]]'' by the Greek poet [[Biography:Homer|Homer]], the god [[Biology:Hephaestus|Hephaestus]] cleans his hands, face, and chest with a sea sponge, and the servants in the Odysseus palace used sea sponges to clean the tables after the meals the suitors of Penelope had there. The Greek philosophers [[Biography:Aristotle|Aristotle]] and [[Biography:Plato|Plato]] mentioned sea sponges in both scientific and historic contexts in their works.<ref name=":0">{{Cite web|url=https://www.seaspongecompany.com/pages/sea-sponge-history|title=The History of the Sea Sponge|last=Inc.|first=The Sea Sponge Company™|website=The Sea Sponge Company™ Inc.|access-date=2018-04-14}}</ref><ref name=":1">{{Cite web|url=http://www.kalymnos-shop.gr/en/blog/natural-sponges/natural-sea-sponges-and-sponge-diving-history|title=Natural Sea Sponges and sponge diving history|website=www.kalymnos-shop.gr|language=en|access-date=2018-04-14}}</ref> Ancient Greeks and Romans also used sea sponges tied to sticks for anal hygiene, a tool known as the xylospongium, and washed them with sea water.<ref>{{Cite news|url=https://mundoestranho.abril.com.br/historia/como-era-feita-a-higiene-bucal-antes-da-pasta-de-dente/|title=Como era feita a higiene bucal antes da pasta de dente?|work=Mundo Estranho|access-date=2018-04-14|language=pt-BR}}</ref>

[[History:Ancient Rome|Ancient Romans]] used sea sponges extensively for hygiene, as well as other uses. The belief that sponges had therapeutic properties led to their usage in medicine for cleaning wounds and treating disease.<ref name=":0" />

In the [[Religion:New Testament|New Testament]], a Roman soldier offers Jesus Christ the [[Engineering:Holy Sponge|Holy Sponge]] soaked in vinegar on the tip of his spear (some versions say staff) for Jesus to drink during his [[Religion:Crucifixion of Jesus|crucifixion]].<ref name=":1" /><ref>{{Bibleverse|Matthew|27:48|NIV}}</ref>

Synthetic sponges were made possible to be manufactured only after the invention of [[Chemistry:Polyester|polyester]] in the 1920s and the commercial production of [[Physics:Polyurethane foam|polyurethane foam]] in 1952.<ref>{{Cite web|url=http://www.vortex-power.com/eng/home2.html|title=Polyurethane Foam Kitchen Sponge. History of Origin — Vortex Power|website=www.vortex-power.com|access-date=2018-04-14}}</ref><ref>{{Cite web|url=http://www.whatispolyester.com/history.html|title=History of Polyester {{!}} What is Polyester|website=www.whatispolyester.com|language=en-US|access-date=2018-04-14}}</ref>

==Material==
Synthetic sponges can be made of polyester, polyurethane, or vegetable cellulose. Polyurethane is used in polyester sponges for their abrasive side. Polyester sponges are more common for dish washing and are usually soft and yellow.<ref name=":2">{{Cite web|url=http://www.corazzi.com/pulizia-domestic/dom-converters/sponge-scourers/polyester-sponge-and-cellulose-sponge/|title=Polyester sponge and Cellulose sponge|last=S.r.l.|first=Corazzi Fibre|website=www.corazzi.com|language=en-US|access-date=2018-04-14}}</ref><ref>{{Cite web|url=https://www.par-group.co.uk/rubber-and-polyurethane/polyurethane-engineering/polyurethane-sponge-dynathane/|title=Polyurethane Sponge - Dynathane {{!}} PAR Group|website=www.par-group.co.uk|access-date=2018-04-14}}</ref>  [[Earth:Microplastics|Microplastics]] and nanoplastics can be released from kitchen sponges during use.<ref>{{cite journal |last1=Luo |first1=Yunlong |last2=Qi |first2=Fangjie |last3=Gibson |first3=Christopher T. |last4=Lei |first4=Yongjia |last5=Fang |first5=Cheng |title=Investigating kitchen sponge-derived microplastics and nanoplastics with Raman imaging and multivariate analysis |journal=Science of the Total Environment |date=June 2022 |volume=824 |pages=153963 |doi=10.1016/j.scitotenv.2022.153963|pmid=35183629 |bibcode=2022ScTEn.824o3963L |s2cid=246994693 |doi-access=free }}</ref>

Vegetable cellulose sponges made of wood fiber are used more for bathing and skin cleaning, and are usually tougher and more expensive than polyester sponges.{{Citation needed|date=September 2020}} They are considered more eco-friendly than polyester sponges as they are biodegradable and made of natural materials.<ref name=":2" /><ref>{{Cite web|url=https://www.mnn.com/your-home/at-home/questions/whats-the-difference-between-cellulose-sponges-and-those-other-kitchen-s|title=What's the difference between cellulose sponges and those other kitchen sponges?|last=Hickman|first=Matt|date=2017-08-21|website=Mother Nature Network|access-date=2018-04-14}}</ref>

==Harboring bacteria==
thumb|right|200px|[[Bacteria from a kitchen sponge]]
A sponge can be a medium for the growth of harmful [[Biology:Bacteria|bacteria]] or [[Biology:Fungus|fungi]], especially when it is allowed to remain wet between uses.<ref>{{cite journal | url = https://www.proquest.com/openview/8508f6cdd54d5692d03ff82c87ed844f/1?pq-origsite=gscholar | volume=62 | title=Reducing bacteria in household sponges | journal=Journal of Environmental Health | pages=18–22}}</ref>

===Cleaning===
Several methods have been used to clean sponges. A 2009 study showed that the microwave and the [[Engineering:Dishwasher|dishwasher]] were both effective ways to clean domestic sponges.<ref name="sciencedirect.com"/> Leaving sponges soaking in a dilute solution of dish detergent discourages bacterial growth.

Studies have investigated the use of the [[Physics:Microwave oven|microwave]] to clean non-metallic domestic sponges that have been thoroughly moistened. A 2006 study found that microwaving wet sponges for two minutes (at 1000 watt power) killed 99% of coliforms, ''E. coli'', and MS2 phages, but ''[[Biology:Bacillus cereus|Bacillus cereus]]'' spores required four minutes.<ref name="sciencedirect.com">{{cite journal | doi=10.1016/j.foodcont.2013.07.026 | volume=35 | title=Hygiene in the home kitchen: Changes in behaviour and impact of key microbiological hazard control measures | journal=Food Control | pages=392–400| year=2014 | last1=Taché | first1=J. | last2=Carpentier | first2=B. }}</ref> After some fires were caused by people trying to replicate the results at home, the study's author urged people to make sure their sponges were wet before treatment.<ref>[http://news.bbc.co.uk/2/hi/health/6293735.stm "Microwave 'sterilisers' warning"]. 24 January 2007. BBC News.</ref> 

== Economy ==
Countries around the Caribbean and the [[Place:Mediterranean Sea|Mediterranean Sea]] are the largest sea sponge exporters, whereas the largest importers are developed [[Earth:Europe|Europe]]an and North-American countries. Tunisia is the world's main sea sponge exporter, exporting 90% of its sponge production.<ref>{{cite web | url=https://amp.theguardian.com/environment/2019/dec/20/tunisian-fishermen-driven-to-perilous-depths-by-mystery-sea-sponge-blight | title=Tunisian fishermen driven to perilous depths by mystery sea sponge blight &#124; Environment &#124; the Guardian }}</ref> {{wipe|France}} is the main importer, being supplied by Tunisia, but France's sponge demand has fallen in recent years.<ref>{{Cite web|url=https://www.fao.org/docrep/field/003/AC286E/AC286E04.htm|title=SPONGES: WORLD PRODUCTION AND MARKETS|website=www.fao.org|access-date=2018-04-14}}</ref> 
{| class="wikitable"
|+Main sponge exporters (in metric tons exported)
!Exporters
!1981
!1982
!1983
!1984
!1985
!1986
|-
|{{flag|Tunisia|1959}}
|74
|71
|84
|81
|91
|88
|-
|{{flag|Cuba}}
|36
|33
|38
|33
|41
|41
|-
|{{flag|France}}
|25
|26
|33
|31
|35
|30
|-
|{{flag|Greece}}
|32
|42
|36
|27
|32
|22
|-
|{{flag|Bahamas}}
| -
|8
|21
|8
|3
|14
|-
|{{flag|Turkey}}
|11
|8
|7
|8
|1
|1
|-
|{{flag|Egypt}}
|5
|4
|4
|2
|4
|8
|-
|{{flag|Japan}}
| -
|6
|4
|1
|1
|6
|-
|{{flag|Philippines|1986}}
|9
|4
|5
|6
|6
|4
|-
|{{flag|Libya|1977}}
| -
| -
| -
|6
|3
| -
|-
|'''Total'''
|'''192'''
|'''202'''
|'''232'''
|'''213'''
|'''245'''
|'''225'''
|}

==Gallery==
<gallery mode="packed">
Image:Sponge Macro.jpg|Macro photograph of the porosity in a synthetic cleaning sponge
File:Chania - Markthalle - Schwämme.jpg|Natural sponges for sale in Crete
Image:Luffa sponge.png|Plant fiber sponge: A [[Biology:Luffa|luffa]] sponge whose coarse texture helps with [[Biology:Skin|skin]] scrubbing and exfoliation 
Image:Spongegourd.jpg|A ''[[Biology:Luffa aegyptiaca|Luffa aegyptiaca]]'' sponge section magnified 100 times
Image:Urethane sponge2.jpg|A close-up of one corner of a urethane abrasive sponge with a top layer used for more intense dish scrubbing
Image:Spugna sintetica.jpg|A close-up of a synthetic sponge's openings
Image:Alceesponja.JPG|A souvenir made out of an artificial sponge
</gallery>

==See also==
*Dishcloth
*[[Chemistry:Ethylene-vinyl acetate|Ethylene-vinyl acetate]] – material that craft foam is made from ethylene-vinyl and acetate
*[[Engineering:Holy Sponge|Holy Sponge]]
*''[[Biology:Luffa aegyptiaca|Luffa aegyptiaca]]''
*Sponge metal
*[[Physics:Capillary action|Capillary action]]
*Shower puff

==References==
{{Reflist}}

{{Cleaning tools}}

[[Category:Cleaning tools]]

{{Sourceattribution|Sponge (tool)}}