While Polylactic Acid (PLA) is made from renewable and natural materials such as corn, this does not automatically mean it is sustainable and can be recycled. PLA is known to be ‘compostable’ but there is a big difference between a product being ‘compostable’ and ‘recyclable’.
Compostable plastics are designed to be broken down in a different way and should be disposed of through organic waste bins. They decompose into nutrients that can be added back into the soil as fertiliser. Whereas the recycling process does not return materials to the earth and instead takes materials and converts them into new usable materials. We further explore the differences between compostable and recyclable in this article.
With the new plastic tax bill coming into place next month, you may be wondering why PLA does not qualify. Read on to find out the truth about PLA and its sustainability.
The misconceptions of PLA
Around the world, PLA has been advertised as a renewable, biodegradable, plant-based alternative to petroleum-based plastics. Due to PLA being made from fermented starch, the plastic was said to be “carbon-neutral” and “non-toxic”, so many businesses made the switch from their petroleum products.
With reducing plastic consumption in mind, PLA seemed to be a win in terms of sustainability and became a popular alternative. Unfortunately, as more information has come to light, it became apparent this is far from the truth.
The environmental problems with PLA
When taking a look further into PLA plastics, many environmental issues revealed that zero waste was a complicated and unattainable path. The biggest problem with PLA is the very specific conditions needed in order for it to be properly composted.
Instead of being recycled with regular plastic materials, PLA needs to be sorted separately and brought to a ‘closed composting environment’ as otherwise it contaminates the recycling stream. However, when sent to industrial composting facilities it is then essential that PLA plastics are heated to 140 degrees and exposed to special digestive microbes that can biodegrade.
So, with the demanding conditions for biodegradation and the fact that it biodegrades very slowly, combined with the increased pressure on consumers to ensure their PLA waste is being sent to the right facility, makes it practically impossible for the products to complete their life cycle as marketed. It’s thought that because of these difficulties, PLA plastics more often than not end up in landfills or oceans – so not as sustainable as it may seem!
There is also the issue that many big cities do not even have the correct industrial facilities for the process, which leads to the PLA being discarded into landfills. Analysts have even estimated that a PLA bottle could take anywhere from 100 to 1,000 years to decompose in a landfill, and if that isn’t bad enough, as it decomposes it releases methane – a gas 23 times more potent than Carbon dioxide.
There are other factors to consider as to why PLA is not as sustainable as first thought. For example, the fertilisers and pesticides used to grow the plants that make up PLA could release more pollutants. The fertilisers used to grow PLA feedstock are also responsible for a large amount of GHG emissions. Not only that, but the amount of water needed to make PLA is 38% more than polypropylene and 10% more than PET.
Reference swiftpak.co.uk