Review: Leather sustainability, an industrial ecology in process

Leather production is a historic industry that still has an economic influence throughout the world. Leather making is done following a sequence of complex chemical and mechanical steps, using energy, quantity of water and chemicals, and generating waste. For several decades, many organizations have been working toward a cleaner tannery industry resulting in better practices, saving energy and water, and increasing wastewater treatment efficiency. Solid waste management remains a big issue. Another question posed today is the use of chromium in tanning. It is why a lot of research is now dedicated to metal-free tanning solutions. Chromium alternatives exist but none can actually rival all the advantages of chromium and a balance must be found with environmental issues. To measure the environmental performance of leather, several tools are available. The LWG (Leather Working Group) audit is one of them. On the side of consumers, some reliable leather ecolabelings exist. Finally, life cycle assessment (LCA) is the most exhaustive tool for characterizing leather's environmental performance. Numerous LCA studies done in the past two decades underline the difficulty in obtaining general results, considering the large variety of processes used depending on tanneries, localization, and raw materials. In addition, the data available for LCA are still poor in regard to the specific data needed for leather chemicals. The best methods associated with new technologies, audit, and labeling lead leather production into a cleaner and environment-friendly industry.