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Everything that is made in nature is capable of biodegrading back into nature to produce new substances or materials from the old. Biodegradable products can be broken down efficiently if given the appropriate environment to do so. The process in its natural form is perfect and omnipresent. Human participation in this process creates certain materials incapable of decomposing. The biodegradability of an item relies on three major factors. First, anything that is made up of natural substances or materials will return to the earth in some way, providing it has not been altered by manmade substances. The microorganisms responsible for the breakdown procedure do not exist for unnatural materials. Biodegradable products must also break down within a reasonable period of time. Finally, the substance or material must break down into a form that is not harmful to the ecosystem such as water, carbon dioxide, and natural minerals.