Growing environmental concerns have driven a surge in bioplastics, but unclear labelling for disposal is creating challenges, according to a new report from Australia's national science agency, CSIRO.
The State of bioplastics in Australia report found consumer confusion over bioplastics, with many bioplastic items ending up in landfill or contaminating recycling and composting streams.
Plastics derived from fossil fuels account for 3 per cent of greenhouse gases. With global plastic production currently sitting at 460 million tonnes and estimated to double by 2040, demand for sustainable and bio-based alternatives is increasing.
Bioplastics is a term that refers to plastics made from petro-chemical-based or renewable natural materials. Not all bioplastics are environmentally degradable, however, many are, with low carbon, biodegradable and compostable options available.
Dr Albert Ardevol, CSIRO's Plastic Packaging Research Lead, said bioplastics offer a promising solution to reduce fossil fuel dependency, mitigate plastic pollution, and optimise material circulation.
"Bioplastics cover a wide range of polymer types and uses, but there is confusion around terminology and how to process bioplastics after use," Dr Ardevol said.
"Australia doesn't have standardised labelling so it's hard for consumers to understand the different types of materials and how they integrate into existing waste management systems.
"Bioplastics are often a more sustainable alternative. However, if disposed of incorrectly, bioplastics can contaminate recycling and waste streams.
"A large portion of bioplastics end up in landfill, where they can decompose and release methane emissions. This negatively contributes to waste and climate change, and does not achieve circularity."
Global bio-based plastic production has more than doubled since 2010. Close to half of the 2.18 million tonnes of bioplastics manufactured in 2023 was for packaging, the most prevalent type of plastic pollution.
The uptake of bioplastics is currently limited by high production costs, with most bioplastics in Australia imported from Thailand and Brazil.
"Bioplastics make up only 1 per cent of plastic used in Australia which provides a significant opportunity to create commercial opportunities, while reducing impacts on the environment," Dr Ardevol said.
"Polylactic acid (PLA) is predominantly used in Australia for packaging but the majority ends up in landfill, which highlights the need for improved waste management and recycling infrastructure.
"Polyhydroxy acids (PHA) offers good commercial viability for single-use products as it can break down in various environments.
"Bioplastics can also replace conventional plastics in horticulture, agriculture and biomedicine, such as mulch film ."
Dr Deborah Lau, CSIRO's Ending Plastic Waste Lead, said establishing design standards will help further the bioplastics industry in Australia.
"Bioplastics need to be designed and considered within the broader plastic waste system," Dr Lau said.
"Raw materials used for bioplastics production in Australia are mainly sugarcane, corn sugar, and starches for PLA, bio-polyethylene (BioPE) and PHA, and some need specialist waste management facilities.
"As they are not accepted in most existing waste collection streams, capacity and infrastructure for processing bioplastics needs to be developed.
"Addressing some of the complex challenges across the plastics supply chain will help expand the bioplastics industry in Australia, such as developing new products that overcome environmental, economic and infrastructure barriers.
"For example, CSIRO has established the Bioplastics Innovation Hub with Murdoch University to develop 100 per cent compostable plastics which could break down in both industrial and home composting facilities."
The State of the bioplastics in Australia report is part of CSIRO's Ending Plastic Waste research which aims to change the way plastics are made, used, recycled and disposed of.
