Most of the talk about kitchen sponges is around the amount of bacteria they can harbor. Sure, it's a very good point, but what about the environment?

How often do you change your kitchen sponge - once, twice a week? Imagine that being repeated millions of times each week around the world. It's a lot of waste, especially given that so many sponges are made from plastics, making them yet another item in our home that's derived from oil.

While changing your sponge regularly is good hygienic practice, try to purchase ones that are made from only from cellulose fiber - and the cellulose is sourced from plantation forests or recycled.

There's an added danger with many synthetic sponges these days; often they are impregnated with chemicals such as Triclosan. Triclosan is an antibacterial and antifungal agent and is registered with the Environmental Protection Agency as being a pesticide. It's also used in many antibacterial soaps, deodorants, toothpastes and cosmetics.

Aside from increasing evidence linking triclosan to health problems, it is also believed to destroy fragile aquatic ecosystems; especially algaes that other animals may depend on - either directly or indirectly.

As sewerage and waste water treatment plants cannot remove triclosan and the compound remains stable for long periods of time; it's posing an increasing problem in our waterways - it's now one of the most common man-made chemicals found in U.S. streams.

Any sponge pack that states is anti-bacterial or destroys odors is probably best left on the supermarket shelf as it's likely to contain triclosan or something equally damaging to the environment.

To help keep your "green" cellulose sponge free of nasty bacteria, try to keep it as dry as possible between uses. You can sterilize them by soaking for a few minutes in boiled water, or try a dilute bleach/hydrogen peroxide solution.

Just on bacteria - we seemed to have developed quite a paranoia about these critters. Not only are there good bacteria, but in order to develop resistance to some of the less desirable ones, we do need some exposure to them. While good basic hygiene practices should never be forsaken, all we're doing with disinfecting everything we touch is weakening our immune system and producing more robust bacteria.