Compostable? What it exactly means?
And what the difference between Degradable, Biodegradable and Compostable?
I got in this site, the exaclty answer for what we need.
check this out:
Biodegradable products break down through the action of a naturally occurring microorganism, such as bacteria, fungi etc. over a period of time. These products are usually made from plant or animal sources. Examples of biodegradable include paper, vegetable scraps and some forms of plastics made from ingredients such as corn starch.
There are some disadvantages to biodegradable waste. When dumped in landfills, it's often dug under where the "good" bacteria can't survive in the oxygen depleted environment. It then breaks down under anaerobic conditions which creates methane, a greenhouse gas with over 62 times the GWP (Global Warming Potential) of carbon dioxide. Also, biodegrable waste can contain toxins. For example, human and animal waste, which is considered biodegradable may contain traces of all sorts of toxins such as heavy metals and pesticides depending on the person/animal's diet.
Degradable plastics are oil based and break down through chemical reactions rather than the activity of micro-organisms, so they can degrade in an anaerobic environment into water, CO2, biomass and trace elements.
This is pretty close to biodegrable plastic but "greener". According to the American Society for Testing & Materials, for plastic to be considered as compostable, it must be able to break down into carbon dioxide, water and biomass at the same rate as paper. It also needs to look like compost, should not produce any toxic material and should be able to support plant life. Compostable items are made from plant materials such as corn, potato, cellulose, soy and sugar.
So, just to resume:
Biodegradable - green, but can leave traces of toxins
Degradable - made from oil, but breaks down into harmless materials
Compostable - green from start to finish.. perhaps
So, let's get compostable stuffs now! :)