We all love the sound of a ‘biodegradable’ takeaway coffee cup. Unlike the convectional takeaway coffee cup which is layered with plastic lining, this genius invention makes us less guilty thinking once we finish drinking the coffee, it will disappear, if not instantly, should be in a few weeks.
So as the biodegradable takeaway bowl, straws, wipes, bio-glitters, bin bags, food wrap … you name it! As consumers gain more awareness and governments impose regulations on conventional plastics, the popularity of biodegradable plastics is rising, projected to be a $7.6 billion-valued market by 2027.
Most of us would have used items made out of biodegradable plastics, but have you ever wondered if they really are 'biodegradable'? What price are we paying for the word ‘biodegradable’ to appear on the packaging? Where to from here?
1. What are biodegradable plastics?
Let's start with understanding what biodegradable plastics actually are.
According to Wikipedia, biodegradable plastics are most commonly produced with renewable raw materials, petrochemicals, micro-organisms or all combined. They can be decomposed by the action of living organisms in the form of microbes into water, biomass and carbon dioxide.
Currently, polyhydroxyalkanoates (PHAs, produced in nature by numerous microorganisms) make up about 5% of biodegradable plastics; polylactic acid (PLA, derived from renewable resources such as corn starch) makes up another quarter; approximately half of all biodegradable plastics are starch-blends (meaning petrochemicals could be used).
2. Can all biodegradable plastics break down naturally and safely?
In some countries, validity can be deceiving because companies can use the word 'Bio' without proof. While the words 'degradable' or 'biodegradable' can be thrown around and make a product look compliant, unless they meet Australian Standard AS4736, they may not be able to break down fully with micro-organisms – some may contain trace of plastic. (source)
PHAs will biodegrade in ambient environments including in the ocean, whereas PLAs degrade under particular industrial composting conditions. (source)
The starch-blends, when combined with fossil fuel derived polymers such as PE (polyethylene), PP (polypropylene) and PS (polystyrene), it produces durable commodity plastics such as bio-PE or bio-PET, but they are not truly biodegradable – they are referred to as 'oxo-degradable'. These blends degrade faster than conventional plastics, however, they leave traces of plastic and harmless residues behind.
Image: Bottle made out of red algae powder and water by designer Ari Jónsson, via Dezeen.
3. How long does it take for biodegradable plastics to biodegrade?
An experiment biodegrading plastic bags, conducted by Imogen Napper at the University of Plymouth proves that there is still a lot of knowledge to be gained when it comes to breaking down even biodegradable plastics:
1. A bag labelled as "compostable": it disappeared entirely in seawater. However, in soil, it remained the same, but disintegrated when loaded with items.
2. The bags that were labelled as ‘biodegradable’, ‘oxo-degradable’ and a conventional plastic bag: remained complete in seawater and soil after three years.
One of the most common misconceptions is that biodegradable means a product will easily and quickly disintegrate. In fact, most biodegradable plastics will only do so under very specific conditions, such as being processed at an industrial composting facility.
Thin compostable plastic bags will break down fairly easily. The thicker and stronger the materials are, the harder and longer to biodegrade – some might not break down at all.
4. Can biodegradable plastics be disposed of in recycling bins?
There’s no simple answer when it comes to recycling biodegradable plastics.
Most importantly, you need to know what type of biodegradable plastics they are, otherwise you will be polluting the recycling streams.
According to allthings.bio, bio-based plastics using fossil fuel derived polymers such as bio-PE or bio-PET can be recycled. If plastic is labelled certified compostable, according to bioplastics.org.au, it will need to go to a commercial composting or a commercial organics recycling facility.
Image: from allthings.bio
5. Are my biodegradable plastics sent to the industrial composting facilities?
Technically, products certified with Australian standards AS 4736-2006 and AS 5810-2010 are accepted at commercial composting or a commercial organics recycling facility in Australia.
There are around 150 industrial composting and organics recycling facilities in Australia. In our experience living in the City of Sydney areas, the council provides green waste pickup service and is trailing a food waste collection service. We compost in our backyard and try to include certified biodegradable materials in the soil occasionally.
A realistic answer in Australia at this stage is, no. Most likely the biodegradable plastics would end up in landfills or incinerated. However, we encourage you to check with your local council, or find out from your local industrial composting facilities. Some resources are available at PlanetARK and NSW EPA.
6. Can I home compost biodegradable plastics?
Yes, if the plastic is labelled as being home compostable under the Australian Standard AS 5810-2010, then we encourage you to do so. These plastics can by identified by the ABA Home Composting Logo, which is shaped like a leaf.
7. What are the environmental impacts of biodegradable plastics?
One of the main impacts is that it creates confusion as there’s not enough awareness and infrastructure to support commercialisation. It may discourage recycling, because consumers are under the impression that products will biodegrade quickly. On the other hand, if the products are disposed of in the recycling bins, they may pollute the recycling streams.
While the market for bioplastics continues to grow by 20%-30% each year, it could also encourage more deforestation and growth of genetically modified crops.
Lastly, if tons of biodegradable plastics end up in landfill like everything else, the impact on the environment could be equally harmful, as organic wastes release methane in landfill, which is 23 times more potent than carbon dioxide.
8. Should we use biodegradable plastics at all?
The materials have great potentials in solving some of the world’s most urgent environmental problems, for example, cutting down our reliance on petrochemical products and recycling organic wastes into the products to prevent wastes ending up in landfills.
But like many other innovative solutions (even solar panels!), until we build a holistic environment for the solution – ethical sourcing of materials, consumer awareness, recycling infrastructure and so on, it’s still early to say whether it’s right or wrong to use the materials.
If you choose to use a biodegradable product, make sure you always reuse it and only throw it out when there’s no other option. Know the types of plastics you are using. Choose the certified biodegradable products. Check with your local council on their methods of disposal. Home compost the product if you can.
At ReCo, our laundry powder and dishwasher powder samples are packed in Better Packaging's home-compostable zip lock bags. We also use their mailer bag for our sample delivery instead of the conventional plastic sleeve. Better Packaging’s home-compostable products are certified to biodegrade within 180 days under Australian Standard AS 5810-2010.
We take pride in sticking to our reuse philosophy and encourage our customers to reuse these bags. It isn't until the bag is no longer usable that we encourage at home or local hub composting of the item.
We are in a time where we are all still trying to find viable and innovative solutions to tackle the environmental crisis. We are probably not in a place, where we have it right yet, but we are certainly on our way there. We can’t help to quote Citizen Wolf’s saying again, ‘Sustainability is about progress, not perfection.’ At this stage, it is, and it needs all of us to join this progress to reach perfection.
Check out our samples here.