PLA is a form of plastic that is made from corn. Many local shops and stores now carry containers and cups made from PLA in an attempt to find a more environmentally conscious choice than conventional plastic. Regular plastic lives forever. (click here to learn more about regular plastic). PLA on the other hand is considered a compostable and biodegradable resource. It is often referred to as carbon neutral because is comes from carbon abosorbing plants. PLA can be made from wheat, beets, potatoes and corn. The current manufacturer of PLA, Natureworks, is owned by Cargill, the worlds largest corn merchant. Thus PLA is made from genetically modified corn. There are definite upsides to PLA. The manufacturer of PLA, Natureworks claims that producing PLA uses 65 percent less energy than producing conventional plastics and it generates 68 percent fewer greenhouse gases, and contains no toxins. Take note that PLA is considered COMPOSTABLE. This doesn't mean it will compost in your backyard compost pile. Well, it will eventually but it will take a looonnng time. In a commercial composting facility using a constant 145+ degree temperature PLA plastucs will completely compost in 45 days. There are only about 100 or so commercial composting facilities in the United States. In a landfill PLA takes anywhere from 100-1000 years to decompose. Still better than conventional plastic which NEVER goes away. Since PLA is made from corn it can be incinerated without the release of any toxic fumes.
The most important thing to know about PLA is that it is NOT RECYCLABLE. Every time someone throws a PLA cup into a plastic recycling bin it will contaminate the regular plastic recycling process. So do not put your PLA cup in the recycling bin. Your not doing Mother Earth or her inhabitants any favors by doing so. PLA when properly disposed of in the waste basket PLA is a step in the right direction but not a big enough step.
The bottom line is that consumers need to think more about the packaging that comes with all the stuff they buy. Choose products with less packaging and give your local stores and restaurants feedback that you want less packaging. The best choice is to bring your own cup with you to the (local fair trade) coffee shop. When you have a choice, choose metal silverware instead of plastic and real plates or paper over plastic or styrofoam. If you don't have your own cup opt for paper over plastic. PLA is not the answer to plastic cups and mass consumption.
To learn more you can visit:
Corn Plastic to the Rescue, from Smithsonian.com
Alternatives to Petroleum Based Plastics

(Photo credit BEC, Courtesy Flickr)