There are three types of environmentally friendly plastics:
- Bio-plastics made from natural materials such as corn starch. Unlike traditional plastics and biodegradable plastics, bio-plastics generally do not produce a net increase in carbon dioxide gas when they break down (because the plants that were used to make them absorbed the same amount of carbon dioxide to begin with). Another good thing about bio-plastics is that they’re compostable: they decay into natural materials that blend harmlessly with soil.
- Biodegradable plastics made from traditional petrochemicals, which are engineered to break down more quickly. They contain additives that cause them to decay more rapidly in the presence of light and oxygen (moisture and heat help too). Unlike bio-plastics, biodegradable plastics are made of normal (petrochemical) plastics and don’t always break down into harmless substances: sometimes they leave behind a toxic residue and that makes them generally (but not always) unsuitable for composting.
- Recycled plastics which are simply plastics made from recycled plastic materials rather than raw petrochemicals.