White sneakers look great with nearly everything on nearly everybody, so it’s no surprise they’re having a fashion moment. Adidas sold eight million pairs of their iconic Stan Smiths in 2015 (and that doesn’t include the lookalikes).

Nearly 800,000 Australians buy a pair of sporting shoes in any four-week period. This amounts to a staggering 10.4 million pairs sold every year. Globally, Nike sells 25 pairs of sneakers every second.

But have you ever considered the environmental impact of your favourite sneakers? From materials to manufacturing, they have a hidden cost – but it is possible to find shoes that don’t cost the Earth.

Free Article: The environmental impact of footwear and footwear materials

A pair of runners produces 13kg of CO₂

While little research has been done on the environmental impact of fashion, one study has found that the production of a pair of running shoes emits 13kg of carbon dioxide. The production of the materials involved, including leather, nylon, synthetic rubber, plastic and viscose, also takes an environmental toll.

Sneakers have a high carbon footprint as, unlike other types of shoes, they typically have many distinct parts. This involves steps like injection molding, foaming, heating, cutting and sewing.

Where the shoes are made is also a factor. Overwhelmingly, the world’s sneakers come from China: in 2016 they represented 76.8% of the the global footwear manufacturing market. China’s factories are largely reliant on fossil fuels, increasing their environmental impact.

Making a shoe

So let’s give your sneakers a quick look. The story behind the primary materials of leather, synthetic leather and rubber have a greater environmental cost than you think.

Leather

Leather tanning as an industry is environmentally costly. Facilities need large amounts of water for treatment, and generate significant amounts of solid and liquid waste, which impacts soil and water health.

It’s also costly to human health, using toxic chemicals and heavy metals like chromium that have been linked to cancer in leather workers.

Finally, the majority of leather is cowhide, which has a large environmental impact. The beef industry is the largest driver of deforestation globally. It is responsible for 65% of greenhouse gas emissions from livestock.

As an alternative: Look for chrome-free leather, vegetable tanned leather or leather alternatives like Piñatex, which is made from pineapple leaves.

Synthetic leather

Synthetic leather, which is used in the liner of most sneakers (as well as vegan footwear) may be more eco-friendly than leather, but it’s still not perfect. It’s typically made from plastics like polyurethane and PVC, which contain their own harmful chemical ingredients. And unlike leather, it’s not biodegradable.

As an alternative: Look for vegetable tanned leather, Piñatex, recycled PET or textiles like hemp, jute, wool, or organic cotton.

Rubber

Most sneakers use synthetic rubber in the soles. They are made from petroleum byproducts and are treated with chemical compounds. Like other synthetic materials, manufacturing rubber uses energy and water and creates waste. Chemicals can also leach from the shoe as the sole wears down.

As an alternative: Look for natural or wild rubber, which can be cultivated to aid against deforestation.

By Lisa Heinze, PhD candidate Sustainability, Fashion & Everyday Life, University of Sydney. This article was originally published in The Conversation under a Creative Commons Attribution No Derivatives license. Read the original here.

Chapter 14 The environmental impact of footwear and footwear materials from Handbook of Footwear Design and Manufacture is available to read for a limited time on ScienceDirect now.

The environmental impact of a product throughout its life-cycle is a significant issue. Complex products such as footwear require many different materials and manufacturing processes, all of which have an effect on the overall environmental impact of the product. This chapter reviews the state of research in this area, looking at the effect of footwear materials, production and disposal on the environment and focusing on life-cycle assessment as a means of measuring this impact.

Want to read more?

Handbook of Footwear Design and Manufacture

• Discusses foot anatomy in detail and considers its implications for footwear design
• Looks at design issues from foot and footwear drawing templates to shoe last design and footwear manufacture
• Specific chapters focus on the footwear business, advertising and the environmental impact of footwear manufacture

The book is available now on ScienceDirect.  Want your own copy? Enter STC317 at the checkout when you order on Elsevier.com to save up to 30%