Episode 6: Are Compostable and Biodegradable the same thing?




Compostable, Biodegradable, Design, Sustainability, Fashion, Circular Economy, Organic Cotton.



Welcome to the Fashion Unearthed podcast. If you need help navigating the fashion industry sustainably, you have come to the right place. I'm your host Belinda Humphrey and my hope is to simplify the fashion industry so that businesses can make the best decisions for people, planet and product.


Hello, and welcome to episode six of the Fashion Unearthed podcast. How's everyone doing out there? I think the last podcast I recorded I talked hopefully about being out of lockdown, which is not the case. I'm in Melbourne and our restrictions recently got increased. So I don't want to jinx it this time and just say that wherever you are in the world, and whatever situation you're dealing with, I hope you're finding a little bit of what you need in each day.


So in this week's episode, I wanted to talk about something I see popping up, particularly in the packaging space, but more and more in apparel product innovation, and it probably fits into conscious creation, but like a lot of things, it's also linked to, I guess, a regenerative planet as well. Today, I wanted to get back to nature a bit and talk about the difference between compostable and biodegradable. You might have seen an ad for a compostable t shirt and next minute seen a biodegradable coffee cup and thought isn't that the same thing? They all break down? Well, even though they are often used interchangeably, they aren't the same thing. I also wanted to touch on why it's being talked about more and how you could actually make something that could be compostable.


Okay, so as I got into researching this and double checking everything, I was reminded just how complicated some of the information is out there and how hard it is to just get a straight answer. And putting this together actually took longer than I thought. But I'm guessing you know that and that's why we're here to get a simple answer and practical straightforward information to create your product. So I've done my best to do exactly that.


Right let's start with a definitions. The Cambridge definition describes compostable as something that is compostable can be used as compost when it decays. Their definition of biodegradable is able to decay naturally and in a way that is not harmful. To be honest, I was a bit disappointed. This was not a clear cut answer on the difference and I thought no wonder everyone's confused. But in my research, I often came across the phrase, "All compostable items are biodegradable, but not all biodegradable products compostable".


Thankfully, I eventually found an article by Ocean Watch Australia that broke down the main differences and they said that they were related to three areas, one, their own production materials, two, how they decompose and three the residual elements after decomposition.


Firstly, compostable products are made with organic elements or plants that degrade with time and produce humus upon completion, which is the richest and most important part of all soils. This means that compostable products do not add any toxic elements to the environment after degradation. However, it is important to note that compostable products need a specific environment to degrade, which includes warm temperatures, nutrients, moisture, and plenty of oxygen. And according to worldcentric.org, for a product to be labelled as compostable, the materials must disintegrate by 90% within 90 days of being in a commercial facility. In addition, they must create zero toxicity during the degradation process.


So moving on to biodegradable, the Ocean Watch article describes it as often being used in plastics and refers to any materials which break down and degrade in the environment. This could be plastics but also include plant based materials like corn oil or starch. However, there is the potential for some product to leave toxic waste behind, they will not always assimilate back into the earth. Essentially biodegradable means that it will break down but not potentially into something that is a beneficial product like a fertiliser, that could improve soil health.


So why are we seeing the term compostable being used for packaging and even garments? Well, according to McKinsey, consumers are highly aware of sustainability issues with their concerns accelerating which suggests that this is a drive for businesses to respond to their needs. And in turn, consumers are looking for these labels because they want to do the right thing. But from what I read what to do after purchasing the product can be the missing link. For example, many items that are compostable in soil such as tree trimmings, food waste and paper will not break down in landfill because this environment lacks the light water and bacterial activity required for the decay process to begin.


There was actually a study done called the garbage project, which was conducted by a group at the University of Arizona in America. The project unearthed from landfill hotdogs, corn cobs and grapes that were 25 years old, and still recognisable, as well as new Papers dating back to 1952, that was still easily readable.


Which brings me to another point that even if an item is compostable if a customer doesn't have a compost or access to a commercial composting facility, these items despite the best intentions could still end up in landfill. To add to that some products can only break down in commercial composting facilities, with one reason being that they can reach higher temperatures than at home composters. Also, composting items at home requires a little human intervention in turning the soil to promote oxygen, keeping them deep enough to get to a required temperature and making sure labels or non compostable trims are cut off.


Another point to consider is that even if something is natural, such as linen, there could be doubt over dyestuffs or printing materials which could leach into the soil. So a consumer would want to be very certain of all components before composting at home, particularly if the soil is going to be used for growing food.


So that's probably the most meaty part done, we've covered the definitions and some of the reasons why this terminology is popping up more in the marketing messages, as well as some of the finer points of how to actually close the loop once it gets into the hands of your customer.


So finally, I wanted to touch on some things to consider if you were to design a compostable item in this example and apparel item. This process should start with an understanding of all the materials that are needed to create your item, you will want to break down everything that goes into your garment and the steps and processes it goes through. If you're wanting to make a T shirt that is compostable, you have to consider your material choices based on having it go back into the earth. You're basically designing for the end of life, which is another principle of the circular economy.


Let's use the fabric component. If you're using cotton, the starting point should be organic cotton. Remembering back to Episode Three of the podcast, organic cotton and specifically GOTS accredited cotton is created using no harmful chemicals or pesticides. So it is a good blank canvas to start from. Then after that you would need to look at what are the stages the fabric might go through? Is it being dyed? What is the dye made of? What kind of finishes or washes are you putting on the fabric. And assess if there is anything toxic or harmful that you wouldn't want to be breaking down in someone's home compost.


Then you would analyse and assess everything else that goes into your garment and the process that goes through. The next step would be actually composting those garments to make sure that what you are claiming to a customer is true.


In summary, I want to say that although a complicated space navigate, much like most of the fashion industry, I really like the potential of designing something that is compostable. It makes you consider all the things that are going into your garment and points you towards making choices that will not harm the soil. We need healthy soil to survive and many other organisms futures depend on it too. And designing with this mindset also moves us closer towards a circular economy.


So that's it for this week. I'd love to know what you thought about this week's episode. You can DM me on Instagram or send me an email at info@belindahumphrey.com and you will find the links to the articles I've referenced in the show notes over at belindahumphrey.com/podcast. and if you're liking the podcast, I would love it if you took five seconds to either hit the stars or a little bit longer to leave a quick review on Apple. It really helps the podcast get out there. Thanks so much for listening. See you next time.


Thanks for listening to the Fashion Unearthed podcast. If you want to get in touch head over to belindahumphrey.com or you can find me on Instagram @belindahumphrey_


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