In our 2021 sustainability framework, we defined two goals: 1) using better materials and 2) keeping our product away from landfills. As part of using better materials, we committed to prioritizing Leather-Working-Group-certified (LWG) leathers starting with our SS21 collection. As we launched the first products of this collection on February 17, 2021, we are proud to announce that all our SS21 leathers are from Italian tanneries that are LWG-Gold certified.

The Leather Working Group is the only organization that assesses environmental impact holistically

How is LWG-certified leather better than regular leather? The Leather Working Group is “a multi-stakeholder group dedicated to pushing for environmental best practice throughout the leather supply chain.”1 The Leather Working Groups audits the environmental impact of tanneries and certifies those which comply with their protocols. The certifications span Gold, Silver, Bronze, Pass (non-medal), and Fail. Our tanneries are all certified at the highest level – LWG Gold, meaning they achieve the highest score bracket.

The LWG protocol is a comprehensive assessment of the most relevant dimensions of impact: management of restricted substances (esp. chrome-6), energy consumption, water usage, air and noise emissions, solid-waste management, and liquid-waste management.2

The Leather Working Group’s protocols assess chrome management and therefore certify non-toxicity

Of the above, chrome management was the most important item on our list. Most of our leathers are chrome-tanned. We chose this tanning method for its advantages over the alternative, i.e. vegetable tanning: 1) many colors, including white, are only achievable with chrome tanning, 2) chrome tanning uses significantly less water and energy because it’s faster, 3) the leather is softer and can be thinner, allowing for a more comfortable product, and 4) chrome-tanned leather is water-resistant.

The Leather Working Group is “a multi-stakeholder group dedicated to pushing for environmental best practice throughout the leather supply chain.”

There are two prevalent variants of chrome: chrome-3 and chrome-6.3 Both work as tanning agents. However, while chrome-3 is essential for us humans to metabolize carbohydrates, proteins, and fats, and therefore an essential dietary element (I take it regularly as a supplement), chrome-6 is toxic and can cause respiratory illnesses including respiratory cancer.

Notably, chrome-6 is a big issue in countries other than Italy, where industrial regulation and oversight is weak. Most Italian tanneries have solid processes and prevent the appearance of chrome-6 even without LWG certification. Our goal at Koio, and with our commitment to better materials, however, was to make sure that we avoid chrome-6 in the tanning process. The Leather Working Group assesses the management of chemicals including chrome, so any certified tanneries are doing an excellent job in keeping the chemical environment safe and free from chrome-6.4

The health risks of chrome-6 are only proven for inhalation and oral intake.5 That means it’s primarily a concern for workers at tanneries and the immediate environment of the tannery if wastewater contains chrome-6. This, of course, is reason enough to try and eliminate chrome-6 from the production process. At the same time, we’re glad to make sure that there will be no chrome-6 on our skin as we’re wearing LWG-certified leathers.

Thanks to LWG’s protocol, Koio can be certain that our leathers are non-toxic, use less energy, and consume less water. This is the most impactful step that we can take at this point to make our shoes more environmentally friendly. This is, however, just the beginning of our journey. We’ll keep researching new methods and materials, and will continue to evolve our sustainability activities as technology progresses.

Words by: Johannes Quodt


1 https://www.leatherworkinggroup.com/
2 https://www.leatherworkinggroup.com/contentfiles/Sample-921.pdf
3 https://www.epa.gov/sites/production/files/2016-09/documents/chromium-compounds.pdf
4 https://www.leatherworkinggroup.com/news/latest-news/minimising-the-risk-of-chromium-vi-formation-in-leather
5 https://cfpub.epa.gov/ncea/iris2/chemicalLanding.cfm?substance_nmbr=144