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2020/09/18 How green are compostable plastics? (part 3 of 3)

How green are compostable plastics?

Source from: https://renew.org.au/renew-magazine/reuse-recycling/how-green-are-compostable-plastics/

More on alternative plastics

Bioplastics
The term ’bioplastic’ is commonly used to describe plastic made from organic materials like plants, rather than fossil fuels. There are a variety of bioplastic materials in production. These include plastic made from a combination of starch and biodegradable polyester, cellulose-based plastic, protein-based plastic and aliphatic biopolyesters, often produced from corn or dextrose. It’s important to note that these materials are only biodegradable if they have been designed to be.

The sustainability of these materials varies. Much like biofuels, bioplastics require land dedicated to growing crops to produce plastic rather than food, can contribute to deforestation and may involve the use of pesticides. Many bioplastic products on the market are single-use items that can be just as harmful to the planet as plastics made from traditional carbon sources. Because of these issues, the experts we spoke to say the most sustainable carbon source for new plastics is old plastics, in the form of recycling.

Oxo-degradable plastics
Oxo-degradable plastic (often just called degradable plastic) includes a catalyst which allows it to degrade when introduced to certain temperatures, air or light for a period of time, with the intention that it will degrade faster in landfill or in the environment, where most plastic ends up. This plastic is usually not made from plant-based carbon, and it is specifically not biodegradable. Its degradation process is abiotic, occurring without the help of bacteria or fungi. Some plastic is also marketed as oxo-biodegradable. These products claim to degrade both biologically and abiotically, but most likely take longer to degrade than compostable plastics and may generate microplastics.
 
Case study: Raising the bar

When Ellen Burns started her Ballarat-based healthy snack bar company, We Bar None, she wanted to apply her dedication to sustainability not just to the product, but to the packaging as well. She began looking for home-compostable packaging for her bars immediately. The process was more difficult than she expected.

“I looked into a few suppliers that claimed they had compostable packaging,” Ellen says. “But I found out their adhesives were made from fossil fuels and they weren’t certified compostable.”

Finally, after an 18-month search, Ellen stumbled upon PA Packaging Solutions, the first Australian company to provide certified home-compostable packaging to businesses. Ellen began working with them and inadvertently became the first business in Victoria, and the third in the whole country, to use home-compostable packaging.

When Ellen first began using the compostable packaging, she was keen to test it out herself. She buried some of the packaging in plain dirt in her yard in chilly Ballarat and found it was gone in under two months. Now, she puts the packaging in her own home compost all the time. But she hasn’t had any issue with the packaging—which has a 12-month guarantee, the same as her bars’ use-by date—failing on her. Even samples she kept of the first bars she received with the compostable packaging nearly two years ago still have their packaging fully intact.

In order to inform her customers about how to dispose of the packaging, Ellen has printed instructions on the wrappers. She also focuses on selling to stockists who emphasise sustainability to customers, including a few who sell no plastic products, and working with initiatives like Zero Waste Victoria to encourage changing the culture around single-use plastic.
Ellen hopes that other businesses will see that using home-compostable packaging is possible and affordable.

“I was happy to be the first business in Victoria to use home-compostable packaging, but I am surprised to still be the only business in Victoria after two years,” she says.
Ellen says she has heard from several large Australian businesses who are currently trialling using home-compostable packaging on their products, but it’s more challenging to make that shift at a large company where many people are involved in decision-making. Still, Ellen looks forward to no longer being on the cutting-edge.

The home-compostable wrappers when first placed in dirt (top) and after two months.