Cut the confusion on compostables

Lucy Frankel, Communications Director at compostable packaging manufacturer Vegware, applauds the University of Plymouth’s research on biodegradable carrier bags – it’s a timely reminder that each material can only be recycled in its correct facility.

The University of Plymouth’s research into biodegradable carrier bags is a timely reminder that no material is magic, and can only be recycled in its correct facility. Also, that it’s important to be clearer when using terms like compostable, biodegradable and oxo-degradable.

‘Biodegradable’ as a term is vague and has no defined timescale or conditions. Wood is biodegradable, but a log cabin can stand for generations. Instead, we should say compostable. This means that packaging can break down in under 12 weeks in composting conditions and is therefore suitable for industrial composting.

Lucy Frankel, Vegware's Communications Director.
Lucy Frankel, Vegware's Communications Director
‘Biodegradable’ is further diluted as a term by oxo-degradable plastics. Oxo-degradable plastics are conventional plastics with an additive to make them fragment into small flakes, and they are not suitable for recycling or composting.

Oxo-degradable plastics are being banned by the EU’s Single Use Plastics Directive, but are currently very widespread in carrier bags, clear cups, straws and cutlery – often confusingly marketed as ‘biodegradable’, despite the Advertising Standards Authority ruling it was misleading in the case of Ancol’s dog poo bags.

There is a lot of confusing language used around packaging, making it difficult for the public to figure out how to dispose correctly of different items after use. On-product labelling needs to recognise this, to help avoid the confusion created by compostable packaging printed with vague phrases such as ‘sustainable’, ‘eco-friendly’ and ‘biodegradable’.

Discarding a product in the environment is still littering, compostable or otherwise. Burying isn’t composting. Certified compostable materials can commercially compost with five key conditions – microbes, oxygen, moisture, warmth and time. The UK’s industrial composting facilities create these conditions for a living, and Vegware products are accepted and composted at a network of facilities around the UK, as well as some on-site composting solutions.

The benefits of choosing lower carbon, renewable, recycled or reclaimed materials apply no matter if they’re composted or not. Where suitable composting is not possible, people should put compostable products in general waste, where they perform better than conventional plastics. Incineration studies from NatureWorks show plant-based compostables produce more heat than newspaper, wood or food waste; also that it produces no volatile gases and leaves little residue. In landfill, studies show that compostable packaging is 'essentially stable' and gives off 'no statistically significant quantity of methane'. Food-contaminated disposables, of any kind, are not suitable for mechanical recycling.

With UK food waste collections increasing, I see the role for a compostable carrier bag that can be reused as a caddy liner. In Italy, all carrier bags must be compostable as part of their food waste recycling scheme. Plastic fragments contaminate the fertiliser from food waste recycling, so certified compostable bags are a practical solution.

Anyone who thinks compostable packaging has a role to play should respond to the Defra Consultation on Waste Management Collection Consistency telling them that compostable packaging should be a core material collected by all local authorities.