PLA (Polylactic acid) comes from fermented plant starch (mostly from corn), and is often referred to as corn starch plastic. It is becoming popular very quickly, because corn-based plastic is a more environmentally-friendly alternative to traditional plastics, which are petroleum-based. Many countries are starting to ban plastic grocery bags altogether, like Ireland, China, Uganda, and South Africa, because it is exactly these plastic bags that are responsible for the skyrocketing levels of so-called “white pollution” worldwide. Corn starch plastic is deemed to be a biodegradable replacement, which is quite viable in our world today. (To read about oxo-biodegradable plastics, click here). Let’s examine the advantages and disadvantages of implementing corn-based plastics in every-day use.

Advantages
1.Comes from corn, which is a renewable resource
2.Does not contain toxins
3.Producing this kind of plastic creates much less greenhouse gas emissions than conventional plastic production (a reduction of 68 percent)
4.Corn starch plastic can be composted in facilities for industrial composting
5.65 percent less energy is needed to produce corn-based plastic than to produce conventional plastic
6.PLA plastic is competitive with conventional plastic in terms of cost, since petroleum prices are only going up
7.PLA is more safe, since there is no danger of explosions in its production (as is the case with using petroleum)

Disadvantages
1.Although PLA is compostable, there are very few facilities where this can actually be done (in the USA only about 113 sites for this exist)
2.Most likely consumers will not compost corn starch plastics properly, and just put them in regular recycling. This could contaminate the recycling stream
3.Composting PLA in large quantities could undermine conventional composting, since the polymer contained in corn-based plastic makes regular compost more acidic.
4.Since there is a lack of adequate infrastructure to compost PLA, most of it will probably still go into landfills.
5.MRFs – Material Recovery Facilities – are responsible for paying for sorting and disposing of PLA
6.Because PLA is derived from corn, there are moral issues with it being used for packaging, since there are people in the world dying of hunger
7.PLA is mostly produced from genetically modified corn

(To read get some eco-friendly home tips, click here). So, what we can conclude is that corn starch plastic may sound promising as an alternative to regular plastic, but it is by far not an optimal solution to the overall problem of pollution. A much better alternative is to simply take reusable bags with you to the grocery store and switch to reusable containers for storing food at home. The underlying problem is not so much the plastic itself, but our bad habits of using it and disposing of it almost unconsciously. Eliminate one-time, ‘immediate-gratification’ plastic use, and you are on track to a better environment.
For more information on bioplastics, go to:
http://en.wikipedia.org/wiki/Bioplastic
http://www.worldcentric.org/biocompostables/bioplastics

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