PLA IS NO PLAY --> Polylactic acid (PLA), a plastic substitute made from fermented plant starch (usually genetically modified corn) is quickly becoming a popular alternative to traditional petroleum-based plastics. But is it all that safe for for the environment?
It's marketed as being a. 100% biodegradable AND b. compostable. But before we delve into why it's neither a. nor b. let's do a quick 101 on how we can actually biodegrade and compost something. Here are the facts:
* Biodegradable means that a product can be broken down without oxygen and that it turns into carbon dioxide, water, and biomass.
* Compostable means it requires specific conditions to decompose.
To either biodegrade or decompose you need to have specialised end of life facilities to 'facilitate' these processes. Since these processes are still very unknown to most and since we do not have the right facilities in Australia to take biodegradable and compostable materials at end of life, most will throw these out into the recycling bin which in turn contaminates the process and thus, all recycling will end up in landfill.
Biodegradable plastics are made with 5% cornstarch or vegetable oil, and they cannot be recycled because the starch or oil additive compromises the quality of recycled plastics.
As PLA is made from renewable sources, such as starch (e.g. corn, potatoes, etc.), soy protein, cellulose, and lactic acid, most of which are genetically modified, it can be composted if 3 criteria are met -
1. The PLA fully disintegrates
2. No toxic residues are left
3. The compost supports plant growth
This rarely happens, as we don't have the right conditions to support this at home and certainly we do not have these facilities as yet in Australia.
So basically, PLA being advertised as biodegradable and/or compostable is just that, an advertisement and nothing more. We end up contaminating the recycling process by throwing biodegradable products into the recycling bin, so we double up in the landfill.