Sponge (tool)

A sponge is a tool, implement, utensil or cleaning aid consisting of porous material. Sponges are used for cleaning impervious surfaces. They are especially good absorbers of water and water-based solutions.

Sponges are commonly made from cellulose wood fibres, or foamed plastic polymers. Some natural sponges are still sold for the same purpose, although most natural sponges are now used either as body/facial sponges or as decorating tools used for sponge painting.

There are three other categories of available synthetic sponges, low-density polyether (known as the rainbow packs of non-absorbent sponges), PVA (very dense, highly absorbent material with no visible pores) and polyester.

Polyester sponges are also sub-divided into a variety of types, some being reticulated (artificially broken-in) for ease of use. Other types are double-blown polyester, meaning that they have a high water retention ability, approaching or equalling PVA, but with visible pores and more flexibility of applications.

Harboring bacteria

Kitchen sponges can serve as a medium for the growth of harmful bacteria or fungi, especially when the sponge is allowed to remain wet between uses. Some manufacturers treat sponges with anti-microbials to prevent this. To kill the bacteria on a sponge, one can fully soak it in clean water, then microwave it on high for two minutes. Care must be taken to ensure the sponge is wet, or otherwise the sponge will catch fire during microwaving. cite web|title="MSN article|url = http://www.msnbc.msn.com/id/16796327/wid/11915773&GT1=8921|accessdate=2007-01-25]

Bug Sponge

The 'bug sponge' was the brainchild of Ian Harold Brown of the 3M labs in St Paul, MN. This sponge featured rigid polyether reinforced with an abrasive and hard-wearing polyethylene compound to effectively remove dried-on insect residue from vehicle windshields. Since its introduction in 1974, the bug sponge has been one of 3M's least known success stories.

Tool use by bottlenose dolphins

The use of natural sea sponges as a tool has been observed in Bottlenose Dolphins in Shark Bay. A dolphin will keep a marine sponge on its rostrum, presumably to protect it when searching for food in the sandy seabed.cite journal | author=Smolker, R.A., "et al." | title=Sponge-carrying by Indian Ocean bottlenose dolphins: Possible tool-use by a delphinid }| Journal=Ethology | Year=1997 | Volume=103 | Pages=454-465] The behaviour, known as "sponging", has only been observed in this bay, and is almost exclusively shown by females. This is the only known case of tool use in marine mammals besides Sea Otters. A study in 2005 showed that mother dolphins probably teach the behaviour to their daughters.cite journal | author=Krutzen M, Mann J, Heithaus MR, Connor RC, Bejder L, Sherwin WB | title=Cultural transmission of tool use in bottlenose dolphins | journal=Proceedings of the National Academy of Sciences | volume=102 | issue=25 | year=2005 | pages=8939–8943 | doi=10.1073/pnas.0500232102]

ee also

*Sponge rubber ball

References