Leather, derived from animal hides, has been utilized for centuries as an all-round material due to its availa-bility, durability, flexibility, and aesthetic appeal. However, the leather industry’s environmental impact is per-ceived as unsustainable, especially regarding water usage, pollution from tanning processes, and waste gen-eration. Lately, the sustainability of leather is put into question, with arguments for both its advantages as a durable and circular material and its aledged environmental drawbacks. This paper explores whether leather can be considered a sustainable material in today’s environmentally conscious world.
On the one hand, leather production depends from livestock farming, which provides the raw material to tanning, which ensures its existence preventing the raw material to rot. Both demand significant resources. For example, leather production is highly water-intensive and generates waste. However, many people ignore that more waste and associated sanitary concerns would be generated if these by-products would not be managed properly, adding stress to landfill burden or being incinerated, releasing harmful emissions.
However, waste reduction and eco-friendly tanning processes ensures that leather is part of a sustainable material choice.
Leather is a by-product of the meat industry, using hides that would otherwise be discarded. By repurposing these hides, the leather industry reduces waste. If approached responsibly, leather production could operate within a circular economy framework, where animal products are used efficiently.
Advances in tanning technologies offer eco-friendlier processing options. An innovation in resource effi-ciency is the use of “green chemistry” for tanning, reducing chemical pollution. Some companies are also adopting biodegradable leather finishes to ensure eco-friendlier end-of-life disposal. Similarly, water-saving techniques and closed-loop systems are being introduced to minimize resource usage and environmental impact.
The use of “green chemistry” for tanning approach employs biodegradable chemicals and seeks to replace concerning agents with renewable materials, allowing for safer recycling and disposal. Green chemistry in tanning has led to the development of bio-based polymers as tanning agents, which are derived from renew-able sources and have a reduced toxicity, improving both environmental protection and worker safety. Differ-ent options have been explored such as alginate derivatives. Algin is a carbohydrate that is abundant in the cell wall of brown algae belonging to the phylogenetic class Phaeophyceae. Lignin-based tannins can be used also. They derived from lignin, a natural polymer found in the cell walls of plants, particularly in wood and agricultural by-products. Lignin is abundant and low-cost, making it an appealing option. By using lignin, tanneries can reduce dependency on synthetic chemicals and increase sustainability, as lignin is biodegrada-ble and derived from waste biomass. An alternative approach could be Zeolite-modified biopolymers. Zeo-lites are naturally occurring minerals that, when combined with biopolymers, can enhance tanning properties.
They act as cross-linkers and help stabilize the hide’s structure. They are also known for excellent adsorption properties, which can reduce odours and residual chemicals.
As for the finishing step, traditional leather finishes—used to coat and protect the surface—often involve a thin layer of synthetic, non-biodegradable coatings, such as polyurethane, that hinders the leather’s ability to decompose at the end of its life. Natural waxes, collagen hydrolysates, and natural resins can replace syn-thetic finishes to achieve a biodegradable product without compromising quality. These finishes allow leather to maintain its aesthetic qualities while significantly lowering its environmental impact during disposal, sup-porting a more sustainable product lifecycle.
Closed-loop water recycling systems can become a reality in modern tanneries. By filtering and reusing water within the same facility, these systems drastically reduce the overall water consumption and lower the risk of eventual stress to local waterways. Some facilities can achieve zero-liquid-discharge (ZLD) processes, where all wastewater is treated and repurposed, minimizing environmental impact.
Closed-loop systems extend beyond water reuse; they aim to capture and recycle other resources as well, like energy and process by-products. For instance, tanneries can collect hair and fats removed from hides during leather production and valorise them into other materials or products, reducing thus waste and max-imizing resource efficiency. Certain by-products from the tanning process, such as limed shavings, can be repurposed for gelatine, collagen, or also biofuels.
Leather is a highly durable material. Quality leather products can last for decades, reducing the need for frequent replacements and lowering the overall demand for resources over time. This longevity makes that leather definitely has a potential to be more sustainable than synthetic alternatives. Let’s not forget that fuel-based materials contribute to microplastic pollution.
Additionally, leather is compostable and can be biologically degraded by the action of microorganisms, re-leasing finally the retained carbon dioxide, water, inorganic compounds, and biomass within a period of 35 days.
In conclusion, leather has a bright future as a sustainable material when manufactured with ethical practices, designed for waste minimization, and applying environmentally friendly tanning techniques. With its durabil-ity, flexibility, and aesthetic appeal it brings a real asset to the range of fashion materials. The leather industry is determined to shift toward sustainability and deepening circular economy advantages, with particular em-phasis on enhancing biodegradability.