The news is all about supermarkets switching their packaging away from plastic...but what are these other materials, how do they differ and how do we dispose of them?
Are you trying to make more sustainable choices when you shop, but so confused by all the terminology that is thrown about to try to convince you something is 'green'? You are not alone...
Packaging has become really complicated. Let’s try and cut through the terminology.
First off its important to understand that there is a difference between naming for ‘how it starts life’ and ‘how it ends life’ i.e. material vs behaviour
Plastic material is either fossil based or bio based
- Fossil based: Made from a wide range of polymers derived from petrochemicals.
- Bio based: Made using polymers derived from plant based sources e.g. starch, cellulose etc.
Fossil based plastic can be described as 'bioplastic' if made from at least 20% renewable feedstock.
Either plastic can be designed to be non-biodegradable or biodegradable as it’s the way it behaves that determines it’s classification.
Technically, all plastic packaging is degradable. The word “degradable” just means that something breaks down. However fossil-fuel-based plastic will only ever degrade to ‘micro-plastics’ i.e. smaller and smaller pieces of plastic.
Conventional fossil-based plastics are non-biodegradable. Even “photodegradable” and “oxo-degradable” are both non-biodegradable forms of plastic that have additives to make them break down faster under certain conditions: sunlight and oxidation respectively. Thus creating a worse plastic pollution – a microscopic one we can’t see – now found in every living being in every corner of the earth.
- Recycle (depending on plastic type / location for kerbside collection)
- Landfill / Incineration
Not all degradable plastics are biodegradable: When a plastic is biodegradable, it can be broken down, digested, and processed by the metabolism of micro-organisms to become part of organic living things. This returns them to nature as part of the carbon cycle of the ecology of the earth.
Only bioplastics are considered to biodegrade within any reasonable timescale. Currently there is great deal of research and debate, as different groups try to establish how quickly oxo-degradable plastics (fossil-based plastics with additives) can be reduced to a form where they are actually biodegradable.
Not all bioplastics are bio-degradable. It is also important to note that even some plastics that are made from renewable resources are processed in a way that makes them non-biodegradable.
Biodegradables are not currently collected at kerbside recycling. Currently biodegradable plastics cannot be recycled in the same way as non-biodegradable plastic.
- Landfill / Incineration
Not all biodegradable plastics by definition are compostable. When something is compostable, it means that it biodegrades, but specifically, that it will degrade within a certain amount of time, under certain conditions.
Home compostable material can go to industrial composting but not visa versa. Not all compostable plastics are created equal. While some are compostable at home, most will only break down in higher temperatures that can only be reached in industrial facilities.
Even bioplastic need specific environments to be compostable: For many types of bioplastic, it’s possible to say that it will break down “eventually”, but if you seal it in an air-tight room, it could take thousands of years. The standards organisations that regulate materials have come up with a series of tests and benchmarks, saying that if a biodegradable plastic will completely biodegrade fast enough in a certain type of environment, then it can be labelled “compostable.”
- Industrial Composting (i.e. food waste caddy)
- Home Composting (i.e. compost heap)
- Landfill / Incineration
So seek out bioplastic for composting, right?
THE CHALLENGES WITH DISPOSING OF BIOPLASTIC
Is that it doesn’t quite work as it should…
Currently this only works with packaging labelled home-compostable and you have a compost bin in your garden to put it in.
Otherwise, any compostable plastics have to go in your general waste bin which means ending up in waste to energy incineration or landfill – not the industrial composter…nor even recycled.
The reality is that any packaging gets pulled out for waste to energy incineration. Since most UK household food waste is composted at anaerobic digester plants, which work without heat or oxygen, they can’t break down solid packaging, which even includes the compostable food bag.
There are only 18 plants in the UK that accept compostable plastics, and the sad news is that, even if your food waste caddy goes to one, there’s no way to tell it isn’t fossil-based plastic, so it gets removed.
The company Vegware are working on a scheme called the ‘Composting Collective’ so large institutions and cafes can take back their packaging and pay to get it disposed of at their local ‘in-vessel composter’.
Recycling is not an option either as bioplastics reduce the quality of fossil-based plastic recycling due to the polymers and materials being different.
Currently there is no legislation on packaging labelling so companies can write what they like. This is going to change and the Government is going to be hosting a consultation on bio and compostable plastics at the end of 2019.
It’s all a bit of a mess. And we can only do our best with what we have.
The only sure way not to create waste is to avoid disposables.
Easier said than done but choosing refill shopping wherever possible can help.
(note from unpckd: sorry to be bearer of bad news but some of these facts even we weren't aware of until writing!)Sources: