In this interview, Sean from Gumdrop explains how the company has created a fully closed‑loop system for collecting discarded chewing gum through branded Gumdrop bins, encouraging consumers to dispose of gum properly and returning full bins for free post‑service. The collected gum is processed into a proprietary GumTech polymer, which has been used to develop the Gumboot (a PVC‑free Wellington boot) and the Gumshoe, a shoe whose sole pattern maps Amsterdam’s streets and is made from gum collected in the city. Sean discusses the material’s customizable properties—hardness, wear resistance, flexibility—to meet different product requirements, and the challenges of matching or surpassing virgin‑material performance. He also reveals a new GumTech yarn, a monofilament fiber made from recycled gum and polymers, with potential applications in footwear uppers and textiles. Beyond product development, Gumdrop offers the iCubed consultancy service to help other businesses implement circular, closed‑loop models. The conversation touches on the broader sustainability context: chewing gum is the world’s second most common litter, costing the UK £60‑£150 million annually; gum takes many years to decompose because it is now a synthetic polyisobutylene polymer. Sean emphasizes that true sustainability requires firm management commitment, supply‑chain scrutiny, willingness to innovate, and a mindset rather than a single goal. The interview highlights the novelty of turning waste from the food industry into fashion products, the durability and recyclability of the resulting items, and the economic and environmental benefits of the closed‑loop approach.
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Woo!
Woo! Woo! Everybody get up! It's not just the chewing gum litter that we're addressing here, it's behavioural change as well. People are encouraged to drop their chewed gum into the bins. When the bins are full, the full bins are sent back to us free post under the membership program, and the bin and its contents are fully recycled and turned back into more bins. So it is truly a fully closed loop and the world's first for dealing with chewing gum waste.
Fantastic, fantastic. We're going to come on to how this applies to the fashion industry. Obviously, you have now made a shoe, but it does raise an interesting point of changing consumer behavior.
Indeed, it certainly does. There's clearly a drive from a lot of manufacturers now to incorporate Recycl8 into their products, and it's, it's becoming more and more of an issue, particularly for some of the big manufacturers. It's a target for them. So there's the corporate social responsibility aspect of things in terms of a cleaner environment and, and cleaning up, which we help to address through the Gumdrop bin. But in terms of sustainability, what you're looking at is you're looking at, you're supply chain and you're looking at your raw materials and how sustainable are they. So it makes sense, doesn't it, to be using as much recyclate as you can in your product.
Yeah, absolutely. It must be quite hard to separate because obviously not everyone puts the right thing in the right bin.
No, that's absolutely true. And what we— we end up with some quite interesting things in our bins. We do end up with cigarette butts in there, We even end up with coins, would you believe? Wow. So people throw away money, albeit money of very low denomination, but it does appear in our bins and our process deals with that. We do separate it at the early stage in our process.
That's almost ironic in a way, they're throwing away money and you're taking actually their chewing gum and turning that into products as well.
Well, I must say we're not making a huge amount of money from discarded money. It's, yeah, it's It's present in some of the waste, but not all of it.
Yeah. So the chewing gum you've now turned into a shoe.
We developed some time ago a compound which was suitable for footwear, and we developed the Gumboot, which is a Wellington boot. Took us about 3 years to develop the compound for that, to give us the properties that we needed. But the Gumboot is our replacement for a standard PVC Wellington boot. and it offers a number of advantages. One, because clearly we're using recycled material, and two, because we achieve a lower density, so we can get a 30% higher yield from a given quantity of our Gum-Tec material than you would get from a standard PVC.
Okay.
So that was our, that was our intro, if you like, to footwear. Since then, we've done other projects. We partnered with Barker Shoes in the UK to produce a recycled crepe sole for their brogues.
Okay.
And then came the Gumshoe project. And Gumshoe is the result of the collaboration between I Amsterdam, which is a city campaign based in Amsterdam, and Gumdrop, obviously, and Leo Burnett, which is a division of the Publicis Group, an ad agency.
Okay.
And the Gumshoe actually is, is is designed to, it's designed to highlight the gum litter problem in Amsterdam. The tread pattern on the sole of the shoe is actually a map of the streets of Amsterdam, and the soles are made with gum that was collected on a campaign in Amsterdam. The initial run of the Gumshoe was 500 pairs, and they sold out remarkably quickly before they properly come to market, in fact.
I'm sure. With soles of shoes, footwear, durability is a big thing.
Of course.
So I assume that it's particularly durable as well.
It is durable. Typically what we have to do with any new project and any new product that we go into is we have to look at what our customer requires in terms of physical properties, and then we have to match those. So our Gum-Tech material, it is varied according to the application. So you might require something which is a bit harder, something which is a bit more wear-resistant, something which is a bit more flexible. And this is quite a challenging part of each new project that we face because we have to sometimes understand a new sector, a new product, a new application, And we have to tailor our compound to either match and replace an existing compound which is made from virgin material, or it would be just a fresh project. So we're developing, you know, it's a clean sheet of paper, as it were, but we still have to deliver the properties that the customer requires.
Yeah. Is there any other— I mean, you've made shoes from it. Could you make any other maybe textiles from it?
Indeed. In fact, a very recent development for us is a project that we're currently working on to create a GumTech yarn. And this is a monofilament fiber made using our GumTech technology, using recycled chewing gum and recycled polymers. And this is showing quite a lot of promise. It will take color and it can be air jet entangled to produce fluffier, larger diameter yarn.
Okay.
And we're very hopeful that we might be able to get this into the uppers of footwear and possibly into textiles.
Okay, I was going to say, what kind of applications could you make from that yarn?
Yeah, well, you know, many and varied. I mean, we're open to suggestion. We're, as I say, we're at the very early stages of this, so we're, you know, we're quite excited about it, but there's some work to do yet.
I bet, I bet. Naturally, I assume that your background isn't in fashion.
No, indeed, my background isn't. Anna's closer than me in that she's a designer. Yeah, so that's really, you know, quite close, I guess, to fashion. My background's in fact in the food industry.
Okay.
Operations management, and I'm in sort of process engineering, or was in process engineering and operations management, and my qualifications are in fact in maths. Okay. So it's a foray into, you know, a completely different sector for me, but For us as a recycling business, there's a commonality, and recycling is recycling no matter what sector you're looking at. It's just how you apply it. So it's really about looking at, you know, the different waste streams, understanding the best way of dealing with them, and encouraging people to be responsible about it. Through our experience and the knowledge that we've built up in developing Gumdrop to its current state, We've also launched our iCubed program, which is a consultancy service, because we found that we were being asked quite a lot by different businesses how to go about producing circularity in their business model. And we've, you know, we've launched a service to help those people, to help our clients in terms of introducing the circularity, the closed-loop process wherever possible into their supply chain.
Yeah, it's very important, and especially for the fashion industry right now. It's an industry that's under a lot of heat for being not very sustainable in its practices. I think sometimes unfairly so. I think a lot of industries, I mean, you mentioned the food industry, certainly a lot of waste there as well. And so every industry has a lot to learn. But in terms of closed loop, it's something that many companies are investigating, seeing what they can do to have more circular business models.
Exactly, yes. And, you know, we find ourselves looking at various different problems and challenges, which we find really quite stimulating. We like trying to help. Not only does it help our customers, but it helps us with our message as well for Gumdrop. For sure. In terms of sustainability, you know, what you're looking for in a business to actually deliver that in your business model is you're looking for a commitment to look at all of the aspects of the business, to introduce sustainability wherever you can, to closely examine what you do. And that requires, you know, a forensic amount of detail sometimes.
Absolutely, absolutely.
You're looking at sourcing, as I mentioned earlier, raw materials, you're also taking an overview of the entire supply chain. You're looking at other businesses and other sectors to see how they do it, what they're doing, can you harvest anything from them and their experience and their models. And you're also looking for, you know, an enlightened management team who will support sustainability initiatives in terms of training and in terms of financial support. Because you have to realize that the sustainable option isn't always the most cost-effective one.
Yeah, I think companies have to be prepared to lose maybe a little bit on the bottom line.
They do.
At least in the first instance.
Exactly, because as it becomes more of a way of life, the cost will come down.
Absolutely. It's interesting that you're taking a waste product from a completely different industry and putting that into a fashion product, because we see people with circular models in fashion taking waste textiles and turning that into new fashion, whereas you're taking waste from a completely other sector and turning that into fashion.
Indeed, and we're introducing our Gum-Tech compounds into other sectors too, so it isn't just fashion, it isn't just footwear. There are many different applications that we're currently looking at, some quite exciting projects in the pipeline.
Excellent, well, looking forward to hearing about those. With regards to the shoes, there are more ways that you can be circular in that you're making shoes, which are also a piece of fashion that can be thrown away or discarded and fall into that bracket of the sort of irresponsible consumer behaviours with regards to their clothes.
Indeed, and what we do at Gumdrop is we strive to make sure that everything that we produce, all of our materials and any products that we go into, are themselves recyclable. So our GumTech, our GumTech compounds contain 100% recycled polymers, and we're making sure that the end product containing our material is also recyclable. And so we actually offer a free post service at Gumdrop to take back any of the products that we go into, that we make, that have our Gumdrop logo and GumTech logo on. They can come back to us to be recycled back into material again. So we certainly don't want to be adding to the pile of the mountain of plastic waste which is out there.
Absolutely. So do you have any insight into the manufacturing process? Because it can be quite intensive to make shoes and collect all this gum and turn it into a product.
Sure. Well, of course, all processes require energy, don't they? But what we've done with our GumTech compounds is we've made sure that we're as efficient as we possibly can be. And going back to the production of the compound, we are better than virgin compounds. We're not using virgin materials, so there is less of an impact in terms of the life cycle analysis of our materials. And as I mentioned before, what we also do in terms of the finished articles that contain our compounds, we make sure those are recyclable so they can come back to us free post.
Yeah, yeah, very good. Do you have any interesting sort of facts or figures about this industry?
Yeah, well, you know, it wasn't until 2005 that chewing gum was actually designated as a litter, believe it or not. And as already mentioned, it is the second most common litter across the world. In the UK, we spend, depending where you look, somewhere between £60 and £150 million a year dealing retroactively with chewing gum problem in terms of chewing gum on the streets and chewing gum litter in general. Um, yeah, it's, it's a, it's a lot of money. Um, in, in our, you know, in our compounds, we use, um, we use less oil than they use in creating compounds from, from virgin materials. We are fully closed loop, and we offer our end-of-life recycling sort of promise.
Yeah, um, because how long does it take for a chewing gum to decompose?
I mean, very, very many years. Um, chewing gum, um, it used to be made from a natural gum, was the basis of chewing gum, called chicle, which came from Mesoamerican trees. Um, where we're at now, because of the scale of the industry and demand, um, for the chewing gum product, um, is The base for chewing gum is a synthetic, it's a synthetic polymer, which is polyisobutylene, okay, or PIB rubber.
Okay.
Now this is a petrochemical origin. Yeah. And it's typically found in things such as inner tubes for tires, football bladders, electrical insulation tape, the insulation on electrical wires. It's also found in barrier films because its barrier properties are very high. It's found in, let me think, it's found in sealants, and it's also found in adhesives and also two-stroke lubricants.
I want to finish on more of a wider sustainability angle here, because naturally, as we mentioned earlier on, the fashion industry is going through big changes at the moment, is using technologies, whether they are digital or analog, to become more sustainable. From your perspective, what does it take for a company to be truly sustainable?
Yeah, as I've kind of touched on, I think it requires a complete commitment. It requires a company to be open-minded, to not see barriers, to sort of really try to innovate and to look at their waste streams and their supply chains through a different set of eyes, if you like. And really consider and be creative in terms of what those waste streams could or might be able to be used for. And that requires a commitment at management level in terms of training and funding and time indeed, because if you're not giving people the time to actually consider and address this issue, it won't be addressed properly. So it needs a very, very firm commitment I think in terms of all of those things to be able to be truly sustainable. And nobody's going to get it right straight away. It's an ongoing process and there will be aspects due to a lack of technology perhaps that we simply can't address at the moment because the technology is actually not there. But for sure, there are many different materials that are going to, you know, going unused and in the worst case going to waste, which might otherwise be recycled, not necessarily into the same business but possibly into another. And it's all about looking for those applications and uses to become more generally sustainable.
Yeah, so it's not really a goal per se, more of a mindset?
I think so, and you've got to have that mindset to achieve the goals that that come along the way.
Yeah, absolutely. Sean, thank you so much for joining us.
