-sponges- - -KINGDOM OF JOGA-

*a ‘sponge’ is a ‘tool’ / ‘cleaning aid’ made of ‘soft porous material’*

Typically used for cleaning impervious surfaces, sponges are especially good at absorbing water and water-based solutions.

Originally made from natural sea sponges, they are most commonly made from synthetic materials today

Etymology

The word comes from the Ancient Greek term σπόγγος (spóngos),[1] which in turn is probably derived from a mediterranean pre-indo european substrate

History[edit]
The first references of sponges used for hygiene dates from the Ancient Greece. Competitors of the Olympic Games bathed themselves with sea sponges soaked in olive oil or perfume before competing. In the book Odyssey by the Greek poet Homer, the god Hephaestus cleans his hands, face, and chest with a sea sponge, and the servants in the Odysseus palace also used sea sponges to clean the tables after the meals the suitors of Penelope had there. The Greek philosophers Aristotle and Plato also mentioned sea sponges in both scientific and historic contexts in their works.[2][3] 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.[4]

Ancient Romans also used sea sponges extensively for hygiene and other uses. The belief that sponges had therapeutic properties led to its usage in medicine for cleaning wounds and treating disease.[2]

Sea sponges were used as tampons by women throughout history[citation needed] and are still used as a cheaper and more eco-friendly alternative to fibre ones.[5] However, researchers do not recommend using sea sponges as tampons, as they may contain dirt and microorganisms, especially if poorly sanitized.[6][7]

In the New Testament, a Roman soldier offers Jesus Christ a sponge soaked in vinegar on the tip of his spear (some versions say staff) for Jesus to drink during his crucifixion.[3][8]

Synthetic sponges were made possible to be manufactured only after the invention of polyester in 1941 and the commercial production of polyurethane foam in 1952.[9][10]

Material[edit]
Synthetic sponges can be made of polyester, polyurethane, or vegetal 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.[11][12]

Vegetal cellulose sponges made of wood fiber are more used for bathing and skin cleaning, and are usually tougher and more expensive than polyester sponges.[citation needed] They are considered more eco-friendly than polyester sponges as they are biodegradable and made of natural materials.[11][13]

Harboring bacteria[edit]

A sponge can be a medium for the growth of harmful bacteria or fungi, especially when it is allowed to remain wet between uses.[14]

Cleaning[edit]
Several methods have been used to clean sponges. Studies have investigated the use of the 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 Bacillus cereus spores required four minutes.[15] 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.[16] A 2009 study showed that the microwave and the dishwasher were both effective ways to clean domestic sponges.[15]

In economy[edit]
Caribbean and Mediterranean developing countries are the largest sponge exporters, whereas the largest importers are developed European and North-American countries. Tunisia is the world’s main sponge exporter, exporting 90% of its sponge production. France is the main importer, being supplied by Tunisia, but France’s sponge demand has fallen in recent years.[17]

Main sponge exporters (in metric tons exported)
Exporters 1981 1982 1983 1984 1985 1986
Tunisia 74 71 84 81 91 88
Cuba 36 33 38 33 41 41
France 25 26 33 31 35 30
Greece 32 42 36 27 32 22
Bahamas – 8 21 8 3 14
Turkey 11 8 7 8 1 1
Egypt 5 4 4 2 4 8
Japan – 6 4 1 1 6
Philippines 9 4 5 6 6 4
Libya – – – 6 3 –
TOTAL 192 202 232 213 245 225
Gallery[edit]

Macro photograph of the porosity in a synthetic cleaning sponge

Natural sponges for sale in Crete

Plant fiber sponge: A luffa sponge whose coarse texture helps with skin scrubbing and exfoliation

A close-up of one corner of a urethane abrasive sponge with a top layer used for more intense dish scrubbing

A close-up of a synthetic sponge’s openings

A souvenir made out of an artificial sponge