Oh dear, you've just bought a pair of fine, perhaps second-hand footwear, turns out there's a new problem: the shoe soles! The soles of many shoes are a major environmental problem. They are often made of synthetic materials such as plastic, which contributes to the spread of microplastics in the environment. What about this?
Yikes, shoe soles releasing microplastics
Microplastics are tiny pieces of plastic, usually smaller than five millimetres, that are popping up in our environment worldwide and are a growing problem. They are created by the wearing down or breaking down of larger plastic objects, such as car tyres that lose tiny particles while driving, or by washing synthetic clothes, where millions of fibres end up in the water. Find out more in our article on synthetic clothing and microplastics. Litter that slowly crumbles is also a culprit, and to make things a tad worse, microplastics are deliberately added in a lot of make-up and personal care products to make it more spreadable or give it a coarser texture - like toothpaste. (A microplastic-free toothpaste tip is ReBloom, in case you were startled by this post by now). But even our shoe soles contribute to the microplastic problem, and not by much, it turns out.
The soles of your shoes play an important role in the spread of microplastics.
The shoe sole as a contributor to the microplastics problem
A German study concluded that wear from shoe soles ranks seventh among the major contributors to microplastics. That is more than, for example, microplastics from plastic packaging (rank eight), washing clothes (rank 10) and microplastics from cosmetics (rank 17). This is something you don't read much about, while there are alternatives. So if you have the option, preferably choose shoes with a sole made of a natural material. Ultimately, all these microplastics - including from our shoes - end up in our rivers, oceans and even in our food, with potentially harmful consequences for people and nature.
Durable shoe soles: materials, materials, materials!
We would thegreenlist.nl wouldn't be if we didn't also come up with some tips. Because yes, you can also choose shoe soles that are more sustainable. Or well, you can check what the sole is made of when buying new shoes.
- A great alternative is natural rubber. Although a sole made of rubber will also wear out over time, no microplastics enter nature like soles made of synthetic materials. Natural rubber is often extracted from the latex of rubber trees such as Veja, Vans and Wildling Shoes.
- Recycled rubber is also found underfoot. While it is great that no new raw materials have been used to make your shoe soles, it does not get rid of the microplastic problem. Unless it is 100% natural rubber that has been recycled like the hip boot brand A Perfect Jane.
- Thirdly, you sometimes come across shoe soles made of cork at sustainable brands. Cork is a renewable material derived from the bark of cork oaks. It is biodegradable and offers a sustainable option for shoe soles. Cork also has the advantage of being lightweight and offering excellent cushioning, making it comfortable to walk on such as Nae Vegan Shoes and Birkenstock and Saola shoes.
- There are also sustainable shoe companies pioneering their shoe soles. A great example is the brand Allbirds. They have developed a shoe sole made of sugarcane.
- A vegan will disagree, but a leather sole can also be a more sustainable option, especially if you want to avoid microplastics. A leather sole is completely natural and biodegradable. So if you're looking for shoes that are long-lasting and also good for the environment, a pair with leather soles is definitely worth considering. There are good labels for leather such as Blauer Engel, EU Ecolabel, the Leather Standard of Oekotex and IVN Naturleder. Then you know the leather has been tanned honestly and safely without the use of harmful chemicals. Just be careful not to slip, as leather soles can be slippery.
Buying good - virtually unworn - second-hand shoes is a nice sustainable step. But to really reduce the carbon footprint of your shoes, you should also look at the material of your shoe soles. Leave shoes with synthetic outsoles more often to avoid spreading microplastics.
Sustainable shoe soles without microplastics
When we dove into this topic, we quickly discovered that making a better choice does not have to be so difficult at all. If you're looking for new shoes, check out the more sustainable shoe brands first. A nice list of sustainable fashion brands, including shoe brands, can be found here. Often, these sustainable shoe brands already use more sustainable alternatives for their shoe soles, because they definitely do not want to contribute to the microplastics problem. Furthermore, you can find out all about the materials used, including the outsole, in the shoe brands' webshops. Preferably choose a natural sole and avoid synthetic or mixed soles. Good luck and hike!
More sustainable tips from thegreenlist.nl
- Did you know that your slippers can also be sustainable: check out the cutest sustainable slippers and slippers here.
- How do you find sustainable shoes? You can read all about eco-friendly shoes here!
- You can also easily score shoes second-hand: read how to score the coolest pre-loved sneakers here.
Sources: main image: Hicret (Pexels), skateboarder: Cottonbro Studio (Pexels), bottom shoes: Ketut Subiyanto (Pexels), black shoes with white dress: Cottonbro Studio (Pexels).
