Why Degradable Plastic Doesn’t Always Break Down
While biodegradable plastic sounds like a great idea, does it actually work?
Nearly every material will break down eventually. Given natural environments such as seawater, soil and landfill, single-use biodegradable plastic products could biodegrade within a few months to years. That’s much quicker than synthetic plastics which take hundreds of years. However, exactly how long these biodegradable plastics take to breakdown depends on a variety of factors such as temperature and the amount of moisture. While compostable plastics may appear to break down quickly in the compost pile at home, the bacterially created “polyhydroxyalkanoates” utilised in single-use cutlery do need some specialised conditions in order to decompose effectively, such as a microbe-rich industrial composting environments.
Adding to this misconception, biodegradable plastics are not necessarily ‘bio-based’. This means that there is no stipulation that biodegradable plastics are derived from renewable, organic sources such as plants. So while bioplastics aren’t always biodegradable, biodegradable plastics aren’t always made from plant-based materials.
We can break this down further, with three distinct degradable plastic types: biodegradable, certified-compostable and oxo-degradable. While often confused with biodegradable and compostable, oxo-degradable materials comprise their own distinct category. They are not bioplastic nor a biodegradable plastic, but actually a conventional plastic mixed with an additive to imitate biodegradation. Chemicals derived from petroleum are commonly used in creating these ‘degradable’ products. It is common to see polyethylene used in flexible film packaging such as plastic bags, as it belongs to the largest family of polymers produced worldwide. These so-called ‘oxo-degradable polymers’ – that is, plastics that breakdown through an oxidative process – are an excellent illustration of why the subject is so difficult and confusing and there is mounting evidence that oxo-degradable plastics are not suitable for long-term reuse. These materials are non-recyclable and can be incredibly problematic to compost.
For a range of reasons, the European Commission has banned oxo-degradable plastics through the European Single-Use Plastics Directive. Oxo-degradable plastics break down into micro plastics, causing devastating and irreparable environmental and human pollution worldwide. Micro plastics are left in the environment indefinitely.
The tricky thing with ‘going-green’ is that there will always be a range of companies ready to take advantage of the consumer trend. Oxo-degradable plastics are a fine example of this, causing more harm than good. Proper education, certification and standards could go a long way in ensuring that only recyclable or biodegradable products are available on the market, communicating a more transparent process and goal for consumers. Initiatives such as the Plastic Packaging Tax can spread awareness and a sense of responsibility, but overall, compostable and recyclable products seem like the more reliable route.
Head over to our shop to browse our eco-friendly range of products and learn more about how you can move towards greener packaging goals in your business today.