Sustainable Leather Industry

A Sustainable Leather Industry People need energy to sustain their lives, and proper nutrition to obtain that energy. Among many different food sources, animal-based foods are significantly richer in nutrients compared to plant-based foods. Among animal-based foods, red meat in particular is highly nutritious and provides iron, zinc and B vitamins that our bodies require^1,2. Following the slaughter of animals raised for meat, an important waste/by-product of the meat and meat products industry releases a valuable and organically natural material: leather. Leather is the largest organ covering the bodies of all living creatures, with versatile properties and functions. If this natural material is discarded as waste to the environment, it can cause various health and environmental problems. The leather processing sector, a labor-intensive industry, transforms this natural material that most people would not want to touch into leather—a semi-finished product with added value—and thus performs a circular economy function³. People cannot avoid paying a higher price for products made from leather compared to their alternatives. Raw hides used in the manufacture of leather products are subjected to a series of successive and complex chemical and mechanical processes in leather processing facilities, commonly known as tanneries; raw hide undergoes a process in which it is transformed into a resistant, flexible and soft, non-perishable and stable material resistant to microorganism effects and mechanical deformation. In addition, it gains hydrothermal stability, good breathability, durability and high strength⁴. This natural material, depending on the characteristics specific to the animal species whose body it covered, is used in the manufacture of a wide range of different leather goods across a broad product range. Whether tanned leather, parchment, vellum, leather treated with liquid or solid fat, or raw hide, the widespread emergence of these animal skin products over time proves the lasting utility and desirability of animal hides as a material. Traditionally, all of these products have been grouped as leather. In fact, the animal slaughtered for meat continues to live through its skin. The leather processing industry, serving a circular economy function, is one of mankind's oldest pursuits that emerged alongside hunter-gatherer societies^5,6. As humanity developed, throughout history and as it is today, animal raw hides have transformed into a material that can be used for changing purposes ranging from clothing to footwear, from automobile/furniture upholstery to bags, wallets, belts, sports equipment to technical leathers. This production process comprises numerous operations that can be grouped as pre-tanning, tanning, post-tanning and finishing processes. The fundamental purpose of these processes is not to waste the value of a waste/by-product. It is to transform it into a product with added value. As a result, today the global leather products market size has reached USD 440.64 billion. Today, the most important issue for the leather industry is sustainability. In an established industry like leather with a complex global supply chain, it is highly important to internalize sustainability and its implementation. However, sustainability, defined as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs," should not be perceived merely as environmentalism. Sustainability has social equity and economic development pillars. Research on the leather industry mostly evaluates sustainability through the environmental pillar because the industry particularly draws attention to its environmental problems. Environmental sustainability corresponds to the "planet" dimension of sustainability, meaning the need to live within the boundaries of the biophysical environment to continuously benefit from ecosystem services such as renewable and non-renewable resources and waste absorption capacity provided by the environment. Therefore, the primary objective of the industry and the main subject of scientific studies conducted in this context is "environmentally friendly" sustainable leather production. It should be noted here that leather processing is one of the industrial sectors with high potential to pollute the environment due to high-volume solid, liquid and gas emissions, and consequently the leather industry has focused on environmental sustainability⁷. There is no doubt about this. However, by utilizing a material that, when released to the environment, could cause more serious environmental problems and issues affecting human health, the leather processing industry also has a protective effect on the environment and human health. Furthermore, essentially every type of waste resulting from leather production has the potential to be converted into a useful product with present-day knowledge and technology. The social sustainability of the leather industry is equally important as environmental sustainability. Social sustainability encompasses full compliance with product safety regulations, health and safety compliance and commitment to animal welfare principles. As years have passed, sustainability reporting conducted in this scope has gained importance in industrial contexts. Previously, the need for sustainability action and reporting stemmed from the need to meet legal and regulatory compliance requirements. Today, business stakeholders such as suppliers, customers and investors are the main driving forces for communicating sustainability credentials⁸. Furthermore, one of the sources that provides organizations with additional competitive advantages is transparently disclosing sustainability credentials⁹. Sustainability reporting has been found to provide organizations with various benefits. Such benefits contribute to enhancing the reputation of organizations and attract investors¹⁰. Among social sustainability practices are health and safety, employee development, workplace diversity and equal opportunity, obligations and protection regarding employee rights, participation of local communities, work-life balance, occupational safety, child labor issues and animal welfare¹¹. Findings and measurements on the leather industry mostly focus on environmental and economic sustainability issues, while the social sustainability pillar remains more in the background and with limited metrics—most often at the level of "yes-no" criteria. Therefore, there cannot be genuine progress and development in sustainability. Strategies developed for sustainability must take all three pillars into account because the absence of even one will hinder full sustainability development.   References 1. Geiker, N.R.W, et al., 2021, Meat and Human Health - Current Knowledge and Research Gaps, Foods, 10(7) https://doi.org/10.3390/foods10071556. 2. Sharma, S., Sheehy, T. and Kolonel, L.N., 2013, Contribution of meat to vitamin B12, iron and zinc intakes in five ethnic groups in the USA: Implications for developing food-based dietary guidelines. Journal of Human Nutrition and Dietetics, 26(2), https://doi.org/10.1111/jhn.12035. 3. Dixit, S., et al., Toxic Hazards of Leather Industry and Technologies to Combat Threat: A Review, 2015 (January 2015), Journal of Cleaner Production, Vol. 87:30-49. https://doi.org/10.1016/J.JCLEPRO. 2014.10.017 4. Keserwani, P., Jahan, S. and Keserwani, K., 2015, A review on Leather Processing. International Journal of Applied Research, Vol. 1, pp. 977-982. 5. Khan, I.N., History of Leather. Academia. [Online] 28 April 2023. https://www.academia.edu/22929924/HISTORY_OF_LEATHER . 6. Kurian, J. and Nithya, N., 2009, Material Flows in the Life Cycle of Leather, Journal of Cleaner Production, 17(7):676-682. https://doi.   Assoc. Prof. Fazlı Akyüz Department of Textile, Clothing, Footwear and Leather, Leather Technology Program Istanbul University Technical Sciences Vocational School