Biodegradable means that the substance breaks down or changes state chemically from what it is now to something else. We hope that the new substance is less polluting to the environment than what it was originally. An example is foam plastic made from corn starch that breaks down to carbon dioxide, nitrates and a trace of minerals. Non-biodegradable substances remain in the environment without changing chemically or change at a very slow rate thus can cause harm to the environment. An example is plastic jugs used to hold pesticides as well as many other plastics.
The utility depends on what use you may have for the item. If the item needs to last a long time and not deteriorate then non-biodegradable may be the answer. If the item is not needed past packaging and getting to its destination, then biodegradable may be best, especially for the environment.
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