Mini design briefing: the biodegradable plastic debate
Facility managers beware: while biodegradable plastics present an opportunity to solve one of our most significant sustainability challenges, they’re not without controversy
London-based transport and product designers PriestmanGoode are attempting to solve a small part of a very big challenge, with their Design Museum exhibition, Get On Board: Reduce. Reuse. Rethink. The show, which runs in London until 9 February 2020, raises awareness of how much waste is generated by air travel. But more generally, 300 million tons of plastic is produced around the world every year, and it is estimated that only ten per cent of it is recycled.
In the UK alone, buying lunch on the go is now estimated to generate 11 billion items of packaging waste each year, many of them plastic. Since the vast majority of it is not biodegradable, it sits in landfill for hundreds of years. Even worse, the relatively recent identification of microplastics indicate that tiny particles end up in our food and water systems; the potential effects of this are still largely unknown.
A small ray of light
In the midst of this deluge of bad news, bioplastics – derived from plants and typically designed to be biodegradable – offer a small ray of light. Big brands are now exploring their possibilities. Ikea has announced a partnership with the industrial manufacturer Neste to introduce bioplastics into its supply chain. Lego is also experimenting with plant-based alternatives to its famous coloured building blocks. Fashion brands are such eager adopters that analysts at Global Market Insights predict that the bioplastic textile market will reach US $1.4 billion by 2025.
However, these apparent wonder materials are not free of controversy. Arthur Huang, the founder of circular-economy engineering company Miniwiz has argued that bioplastics could potentially be worse for the environment than conventional plastics.
Polylactic Acid (PLA) is the most common type of bioplastic and is made from fermented starch extracted from food crops such as corn, potatoes or sugar cane (although it can also be made from algae). This raises the obvious problem that switching to plastic made from food crops instead of fossil fuels would require large swathes of farmland, potentially accelerating existing issues around deforestation. Huang also claims that the acidity of these bioplastics could result in damage when they are composted, altering the PH of local soil and water systems.
Huang also cited a United Nations report that raised concerns that the public would make less attempt to recycle if they thought that that plastic they used would harmlessly biodegrade if discarded.
Crucially, PLA is compostable but not biodegradable. Microbes will break it down harmlessly into biomass and gas given the right conditions, but if it is simply discarded it breaks down just as slowly as conventional plastics.
It’s not as simple as a backyard compost bin either – it has to be done at an industrial composting plant. A recent study found that compostable plastic bags popular with UK retailers were perfectly usable three years after being buried in dirt. Only around 185 cities in the United States currently pick up food waste for composting, and less then half of those accept compostable packaging. Some industrial composters actively say that they don’t want it, citing the challenge of sorting it from regular plastic and the fact that it can take longer to break down than food waste.
More research needed
All of this has led to calls from experts for the urgent need to study and standardise biodegradable, compostable and bio-based plastics if they’re going to live up to their potential. This is the aim of a recent UK government initiative which put out a request for research on these emerging materials on everything from how long they take to biodegrade to their overall environmental footprint.
While there’s clear opportunity to make workplace supply chains more sustainable, there is also a need for more research to ensure that we’re not simply replacing one problem with another. In addition, we could look at the need for behaviour change initiatives – the obvious short-term solution is to drive out single-use items wherever possible.