Bioplastics & Plastic Degradation
Bioplastics are just plastics made from plants. Bioplastics may or may not be biodegradable, may or may not be toxic.
Plastic is the result of a complex process called polymerization. The building blocks for this process are atoms of carbon and hydrogen. The strong polymer bonds do not easily degrade, which is why plastic is strong yet flexible, and does not corrode or biodegrade. Polymer bonds can be created from oil, gas, or plant materials. The use of plant materials does not imply that the resulting polymer will be better. You could make non-biodegradable and toxic plastic out of organic corn!
There is a lot of chemistry and additives involved in making plastic, and the industry formulas are not transparent. Some bioplastics (not all), are biodegradable and/or compostable. Currently there are not independent standards for what “biodegradable plastic” means, and some plastics that claim to be ‘biodegradable’ or ‘compostable’ may take many years to decompose or may require special high-heat composting facilities (which are uncommon).
Some of these “biodegradable plastics” decompose extremely slowly in regular conditions, and even more slowly in the ocean. And even biodegradable plastics require the use of plasticizing chemicals, which may be toxic and harmful to the environment, or to human health.
If properly designed, biodegradable plastics have the potential to become a much preferable alternative to conventional plastics. At a minimum, these bioplastics must be:
- derived from non-food, non-GMO grain
- compostable and biodegradable
- free of toxins during the manufacturing and recycling process
- manufactured in a sustainable way (water, land and chemical use are considerations)
- recyclable in a cradle-to-cradle cycle
Still, even with the advent of a new-generation bioplastic, manufacturing single-use disposable objects, such as bags and bottles may be preferable but ultimately may not be a sustainable solution. With almost 7 billion people in the planet, a throwaway culture addicted to disposable plastics is likely to continue harming our environment, whether these are made out of oil, or of plants.
We believe that rethinking our habits and our uses of plastic is as important as rethinking the material itself.
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- Study: Bioplastic goods not eco-friendly, UPI, August 2009
- Will My Plastic Bag Still Be Here in 2507?: How scientists figure out how long it takes your trash to decompose, Slate Magazine, June 2007
- Plastic water bottle-makers sued by California over green claims, LA Times, October 2011
- The Promise and Pitfalls of Bioplastic, Time, May 2010
- Study Says Bioplastics Not Necessarily Greener - Environmental Building News, December 2010
- Bioplastics Not So Green - Discovery News, December 2010
- Bioplastics Worse for Atmosphere than Ordinary Plastics - The Green Optimistic, October 2010
- Bioplastics Demand Will Grow, but Not All Bioplastics Created Equal - Plastics Today, January 2011