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Ana Ramos PhD, Research and Development Scientist at BenchSci
Over the past decade, evidence of petroleum-based plastics as a major contributor to pollution and environmental disruption has mounted. As we all take steps to reduce our carbon footprint and environmental impact, many of us are trying to minimize our consumption of plastics. However, adopting a plastics-free lifestyle can be challenging. One way we can support meaningful change is to look to alternative materials such as bioplastics and biodegradable plastics.
But while the idea sounds simple enough, if you find yourself confused about the difference between bioplastics and biodegradable plastics, you are NOT alone! It is not intuitively easy to discern the differences or similarities between the two plastics and, adding to the challenge, they are sometimes marketed as the same thing! So what do you need to know?
Bioplastics VS Biodegradable Plastics
The terms bioplastics and biodegradable plastics are often used interchangeably, which is very misleading because they are, in fact, different types of plastic. On the one hand, bioplastics are made from biomass (e.g. wood, natural fibers) or produced by microbes. Biodegradable plastics, on the other hand, are plastics – bioplastics or other - that can be degraded by microbes. Therefore, while all bioplastics are made from natural sources that are typically more sustainable than petroleum-based plastics, not all bioplastics are biodegradable.
If you have started to look for alternative materials to replace traditional plastics, you may have already come across two of the most common types of bioplastics –nanocellulose and PHAs. Both can be obtained from various natural sources, but my favorite process to source them is through bacterial fermentation – yes, the same process used to make yogurt. Nanocellulose can be found in various forms, as its chemical structure can exist in different shapes and lengths allowing it to be used in a variety of products, including foods, biomedical materials, cosmetics, and even adhesives [reviewed in 1]. Similarly, PHAs (which stand for polyhydroxyalkanoates) are a type of bioplastic commonly used to replace petroleum-based plastics used in packaging solutions such as polyethylene [reviewed in 2].
Read the Label
Both nanocellulose and PHAs are biodegradable bioplastics, which has made them ideal candidates to improve sustainability. However, remember that not all bioplastics are biodegradable. For example, bio-PET, another bioplastic you might be familiar with, is chemically identical to petroleum-based PET, which is commonly used to make plastic bottles. Unfortunately, in the same way PET is not biodegradable, bio-PET is also NOT biodegradable (even though bio-PET is made from biomass [reviewed in 3]). With this in mind, it is important that, as consumers, we pay attention to both the label (i.e. does the product use a bioplastic?), and the type of plastic used. Both pieces of information can help you make a more environmentally-focused decision (I generally do a quick search on the internet to find out if a material is biodegradable or not).
Are biodegradable bioplastics the solution to plastic pollution?
Bioplastics are produced using more sustainable building blocks than petroleum-based plastics. Many production systems even go as far as using organic waste to feed bacteria for the production of bioplastics; a great Canadian example of this approach is Genecis, a startup company that designs microbes that consume food waste to produce PHAs. Innovations like Genecis’ have made me reimagine the future of my organic waste bin when a rotting banana peel can be used to make a fork!
While bioplastics and biodegradable plastics are a more sustainable alternative to petroleum-based plastics, simply substituting all plastics for their more sustainable counterparts would not be enough to eliminate plastic waste. In fact, in October of 2020 Environment and Climate Change Canada shared their plan to eliminate plastic waste by 2030, where they share that “a key part of the plan is a ban on harmful single-use plastic items where there is evidence that they are found in the environment” .
To reach this goal we all need to play our part! I invite you to keep in mind the tips to reduce municipal waste shared by the Government of Canada ; reducing our use of plastics is a much healthier alternative than recycling or using bioplastics. However, for those times where avoiding the use of plastics is not possible, opting for a biodegradable bioplastic over a conventional petroleum-based counterpart is certainly more environmentally friendly.
Learn more about Microbes
High school students are invited to join Let’s Talk Microbes, on Tuesday, November 23rd, This virtual panel of experts will discuss how the science of genomics is building our understanding of microbes – from health to food, to the environment, to the very future of antimicrobials. This Let’s Talk Science Symposium fuels critical thinking about leading-edge technology, and helps prepare high school students to meet the needs of tomorrow.