BIODEGRADABLE?

In our previous article on polyester, we discussed some of the issues around the material's use as a textile medium, in particular its impacts on health. We found that breathing in microplastics shed from polyethylene terephthalate (PET) fibres and other synthetic materials has long-term impacts on lung health, and that long-term wear of the material can lead to a host of skin diseases and infections. 

Not the image of luxury that we had in mind! 

This begs the question, then, of how we can grow and evolve towards surrounding ourselves with an environment that benefits our well-being. 

Bioplastics are becoming increasingly popular among industries looking for more sustainable options. These biologically-derived materials may also have green credentials, meaning their impact to the environment (and, importantly, their impact on us) could be little to none.

However, there are complications with the production and marketing of bioplastics which need to be addressed. Considering this, we will discuss what makes a bioplastic, whether the label of ‘bioplastic’ automatically means that the item is biodegradable, and question; how do we define biodegradable? 

Bioplastics encompass any plastic-like material which are not derived from petroleum; instead they are created from renewable plants and other organic matter. Right away, this is a surefire way to avoid the environmental damage associated with locating and processing oil to make traditional plastic. When speaking of ‘biodegradable’, the Cambridge Dictionary describes the term as, ‘able to degrade naturally and in a way that is not harmful’. This essentially means biodegrading into water, carbon dioxide (CO2), methane (CH4), organic biomass (which can enrich soil) or inorganic compounds such as minerals and salts.

Setbacks surrounding bioplastics and biodegradable plastics are numerous. The first being that the concept of bioplastics being ‘greener’ than regular plastics relies on various different aspects, such as what the bioplastic is made of, and where the ingredients for the bioplastic are sourced. For instance, if ingredients are locally sourced and developed, then this cuts transport emissions. But if, for example, a bioplastic relies upon ingredients from China and production in Turkey for sale in the UK, then it’s easy to see that the carbon saved by utilising a sustainable source material is somewhat defeated by the immense transport costs, both to the environment and the economy.

Another major complication with bioplastics is the fact that not all are biodegradable. This is in part because of how they are processed. For instance, petroleum is a natural liquid from the Earth, but is manipulated artificially to produce synthetic materials. Conversely, in other cases, some petroleum-based plastics can be biodegradable, demonstrating that it is the method in which materials are processed that determines how they break down.  Biodegradation also largely depends on where the plastic is disposed of, thus whether the environment allows the conditions needed for it to degrade.

A 2019 University of Plymouth study demonstrated that a biodegradable plastic which should have been able to decompose in months in a compost bin, was still fully intact after over a year in water. Further, according to Rachel Campbell, Research Associate of University of Sydney, oftentimes, plastic described as ‘biodegradable’ is simply a material which dissipates into smaller plastic pieces quickly. This is an obvious source of microplastic build up, rather than a degradation process.

At this point, it is unclear to consumers how to navigate this confusing market when the vast majority of bioplastic and biodegradable products are sold under the guise of ‘sustainable’. To complicate matters further, currently, only about twenty-five percent of a plastic product must be bio-based in order to be called a bioplastic.

At NEÖSPHERA we consider this to be misleading and the definition of greenwashing. 

We feel altering legislation to ensure the public is aware of the exact ingredients within a material is ultimately transparent; after all, it is a legal requirement to state ingredients in food, and what goes into the environment eventually ends up inside us. Swiftly deteriorating bioplastics at least avoid exposure to hormone-dysregulating chemicals such as BPA (bisphenol A) which is a commonly found component in most traditional plastics. 

Science, climate and environment reporter Emily Chung, points out that if a biodegradable plastic is not accepted by its necessary processing plants, it is sent to an ordinary landfill where the conditions are not fit for degradation. In these conditions, even where plastic does degrade, the CH4 and CO2 is not reabsorbed into the environment but instead released into the atmosphere. Campbell explains that where these materials are able to degrade, it’s due to chemical factors; these additives are needed to encourage microorganisms to break down the material to use as an energy source.

As for bioplastics, they are composed of plant matter, which would mean an increased demand for arable land needed to produce enough plant material, as well as more fertilisers and pesticides being put into the environment.

Although there are various flaws throughout different methods and outcomes of plastics varieties, at NEÖSPHERA we ultimately believe that bioplastic development is the most sustainable method of moving forward. Where bioplastics may put further strain on this form of agricultural land use, our assertion here is that there could instead become more innovative alternatives to the way plant products are grown in the future, such as vertical farming. Also, if waste plant products from the food industry could be utilised to make bioplastics, this would be a potential route towards a circular production process, in which 100% of food bi-products are utilised for the production of new materials, therefore providing a sustainable outcome throughout. 

Bibliography

Cambridge Dictionary. (2024). Biodegradable. Available at: https://dictionary.cambridge.org/dictionary/english/biodegradable 

[Accessed: 30 May 2024]

CBC News. E. Chung (2020). Plant based? Compostable? What you need to know about bioplastics. Available at: https://www.cbc.ca/news/science/bioplastics-backgrounder-1.5485009 [Accessed: 30 May 2024]

Nature, 2021. Advancing biofabrication with synthetic biology. Nature Reviews Materials, [online] Available at: https://www.nature.com/articles/s41578-021-00407-8 

[Accessed: 19 June 2024].

NetRegs. (N.D). Treating and composting biodegradable waste. Available at: https://www.netregs.org.uk/environmental-topics/waste/reduce-reuse-and-recycle-your-business-waste/treating-and-composting-biodegradable-waste/#:~:text=If%20you%20produce%20biodegradable%20waste,and%20sludges%20that%20degrade%20easily. [Accessed: 2 June 2024]

Plymouth Marine Laboratory. (2024). What happens to biodegradable plastics if they enter the sea?. Available at: https://www.pml.ac.uk/news/What-happens-to-biodegradable-plastics-if-they-ent#:~:text=So%2C%20when%20these%20types%20of,the%20sea%20for%203%20years.%E2%80%9D [Accessed: 30 May 2024]

Science Focus. R. Campbell, Alexandra Franklin-Cheung (2024). What does biodegradable plastic biodegrade into?. Available at: https://www.sciencefocus.com/science/what-does-biodegradable-plastic-degrade-into [Accessed: 30 May 2024]