A new type of plastic made from corn starch could solve some of the material’s most egregious crimes
On the heels of our reporting about Canada’s probable move to ban BPA plastics comes a story about researchers working at Missouri University of Science and Technology to develop hybrid plastics that would biodegrade in landfills within four months. As our editor Nicole Dyer pointed out in a comment to the BPA post, the larger and more important issue facing plastics is their propensity to stick around forever. As we pointed out in our article about the waste gyre in the Pacific Ocean, plastics will eventually photodegrade into microscopic bits, but those polymer molecules will forever be inorganic toxins. The Missouri S&T scientists are working to change that by focusing their attention on a biodegradable polyester.
Polylactic acid is a polyester derived from corn starch which decomposes and mineralizes into water and carbon dioxide when composted. It’s already being used in some brands of compostable “plastic” bags. The team is working to blend the acid with other bio- and oil-based polymers to find the right kinds of resins for commercial use. They’re also looking at repurposing waste materials resulting from biodiesel refinement—anything that can be culled from renewable sources. Whether this is a long-term solution remains to be seen.
Via PhysOrg
Seattle follows in the steps of eco-friendly San Francisco with a restriction on plastic shopping bags
Seattle is poised to join the ranks of San Francisco and Ireland by imposing restrictions on the use of disposable shopping bags. The City Council vote on the proposal—expected to pass by a wide margin—will occur this summer and would take effect at the start of 2009. While Ireland and San Francisco have banned plastic bags outright, Seattle’s proposal will instead impose a twenty-cent fee on every paper or plastic bag used by consumers at the point of sale. (The proposal also bans styrofoam food containers.)
The debate over which bag is more environmentally friendly has recently come to an impasse. People long assumed paper was the logical choice because the bags could be readily recycled and would naturally degrade. Plastic, while inexpensive to manufacture and transport, will never biodegrade (and may very well end up floating in the Pacific ocean.) Unfortunately, paper’s benefits at the end of the line are largely outweighed by the disproportionally large amount of water and energy needed to make them in the first place. Not to mention, both will take up landfill space if simply tossed in the trash.
All these factors combined to be the impetus for Seattle’s mayor, Greg Nickels, to introduce the fee proposal.
Via NY Times
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- Tags: Bag Fee, Environment, Plastic Bags, San Francisco, Seattle
