The impact of vegan vs real leather explained
By Nynke Eggen, founder of The Sustainability Club
& Lisa Eggen, founder of Lisa Marin
We receive many questions about vegan leather. What is vegan leather? Why use vegan leather instead of real leather? Is vegan leather more sustainable than real leather? First, let us explain that the only thing that makes vegan leather ‘vegan’ is that the material does not come from animal origin. In other words, that there are no animals used, harmed or killed to create it. However, leather alternatives can still have a big impact on the environment. If something is vegan, that does not necessarily mean that it is also sustainable! There are crucial differences in the environmental impact of the different types of vegan leather. Let us break it down for you.
Images by Desserto, Ananas-nam, Stella McCartney
Many people are aware that the heavy chemicals that are used in the tanning process of leather are polluting to the environment, fewer people realize that leather also plays a huge role in the deforestation of the Amazon.
The big misconception about leather is that it is a natural material and therefore it is biodegradable. Unfortunately, in most cases this is not true.
Research has shown that synthetic leather has only a third of the environmental impact of cow leather.
Times are changing. Many promising materials are being developed to become the new sustainable alternative to real leather.
The environmental impact of real leather
We will not go into the animal welfare issues of leather. We feel that organizations like PETA have done a great job of making this public knowledge. But the production of leather is not only unethical in regard to animal welfare, it is also very bad for the environment. Here’s why:
Heavy chemicals (such as chromium) are needed for the tanning process and to dye and finish the leather. These toxins are harmful for people that have to work with them. There is a correlation between leather workers and their life-expectancy, they usually live less long than their families. Another negative impact of these toxins is that they pollute the soil and rivers when unfiltered wastewater is poured into the environment.
High energy and water use is needed in the processing of leather. One ton of hide (skin) generally produces 20 to 80 m3 of wastewater. With solid wastes representing up to 70% of the wet weight of the original hides, the tanning process represents a considerable strain on water treatment installations.
Leather plays a huge role in the deforestation of the Amazon. Cattle ranching for the production of meat and leather in the largest driver in deforestation in the Amazon countries, accounting for 80% of current deforestation rates.
Image via Unsplash
There are ways to process leather with a reduced impact. By using modern tannery machines for example, water consumption can be reduced by 50% compared to a conventional process. Another technique to process leather in a more natural way, without the use of chromium is ‘vegetable tanning’. These processes are less harmful for workers and for the environment. However, there are still chemicals involved, deforestation is still an issue and animals are still being killed. Globally, conventional (chrome) tanning remains the most widely used method (80-95%).
But real leather is biodegradable, right?
An argument that is often made in favor of leather is that it is a natural product and can therefore biodegrade, making it a ‘waste free’ material. Unfortunately, this is not true in most cases. As leather is most often chrome tanned, the material contains a lot of heavy chemicals. This makes the leather unfit to return to the soil safely. In other words, conventional leather is not biodegradable. There are examples of biodegradable leather. This is leather that is treated with a bio-based tanning process (vegetable tanning). This can in some cases even be compostable.
Going for a vegan option is an ethically and environmentally friendly alternative to genuine leather. Synthetic leather has only a third of the environmental impact of cow leather! Not only that, the report Pulse of the Fashion Industry published by the Copenhagen Fashion Summit in 2017 has found cow leather to have the highest environmental impact of all material groups. Therefore, it is prudent to stop using genuine leather and shift to vegan options instead.
Image from the Pulse of the Fashion Industry report
As we mentioned, ‘vegan’ leather only means animal- or cruelty-free leather. There are still big differences in environmental impact. We have split the most common leather alternatives in three categories and ranked them from high-impact to low-impact.
“PVC is the single most environmentally damaging of all plastics.” – Greenpeace
PVC - The most polluting option is PVC. This material contains many harmful chemicals and is petrochemical based; a non-renewable resource. During the production process, dioxins are released which are toxic to humans and animals. Dioxins remain in the environment long after PVC is manufactured. Through its entire lifespan PVC releases toxic fumes (including dioxins), exposing its user to potential health risk. When PVC ends up in a landfill it does not decompose like genuine leather and can release dangerous chemicals into the water and soil. Burning it is also not a good option, as it then releases even more toxins. All in all, not a sustainable option! Luckily, PVC is being faced out or even banned by many brands.
PU - Polyurethane is currently a more popular leather-alternative in the fashion industry. The manufacturing of PU is cleaner than PVC, but chemicals still need to be used. PU is also petroleum based (non-renewable). There are alternatives to conventional PU: water-based and solvent-free PU. It’s a chemical story, but the bottom line is that there are fewer harmful chemicals needed, and the energy needed for the production can also be lower. PU is applied as a coating on a fabric backing to create the leather look effect. Using a recycled material as a backing can help to minimize the impact of the material.
Bio-based materials - The cleanest or ‘most sustainable’ leather alternatives are made from natural resources. Think about materials like cork, paper, pineapple leaves (Piñatex), apple waste, cactus, mango waste etc. Bio-based means that the material is (partly) derived from biomass (plants). This is favorable to petroleum-based materials because bio-based resources are renewable. Many bio-based leather alternatives are finished or combined with non-biodegradable components like PU, to increase the strength and durability of the material. Unfortunately, this means that the entire material is no longer biodegradable. However, the manufacturing of these materials requires less energy, water and/or chemicals and the materials are usually developed with sustainability in mind. Most of these innovative materials also have a circular component, meaning that they are partly made from waste.
Example: One example of a new bio-based leather alternative is apple leather. This is the material that we have used for the vegan bag collection of Lisa Marin. To make apple leather, waste from the food processing industry in Italy is combined with PU and applied on a backing material made from cotton and polyester.
Image by Lisa Marin
Between the different bio-based materials there are many distinctions in origin, production process and impact. Because these materials are so new, there are no life-cycle assessments (LCAs) available to compare energy footprint, lifespan and after-life. So, we will have to wait to see which of these materials comes out on top as an environmentally friendly alternative to leather.
The future of bio-based leather
There are more exciting innovations happening in this field. Bio-fabricated leather is a promising new material group that is cultured in a lab or brewery. Most of these materials are so new that they are not yet commercially available. Mushroom (or mycelium) leather, is an example of vegan leather that is grown in a lab. Mycelium leather is not yet available on industrial scale. The vegetarian fashion brand Stella McCartney is investing in the development of a new mycelium material and will most likely use it in her bag collection once the material is fully developed.
Bioengineering is also being practiced by Modern Meadows, a well-known startup within the field. They have modified yeast to spit out collagen, this is done in a brewing process similar to beer brewing. The collagen in then moulded, tanned and dyed into a vegan leather alternative that can be fine-tuned to exact specifications on texture, thickness, stretch and colour.
Other promising new leather alternatives are Mirum - a 100% bio-based, fully biodegradable and circular alternative to leather and Reishi - a 100% bio-based mycelium leather alternative that is lab-grown. They should be getting ready to hit the market this year.
Support positive change
Not all vegan leather options on the market are perfect when it comes to environmental impact. As we explained, some vegan leathers contain petroleum-based components for example. However, we would like to argue that new initiatives need to be supported. It will take some work to achieve ‘perfect’ material that is climate neutral, made from renewable resources and fully biodegradable or closed loop. Demand drives innovation and investment. Both are needed to achieve a high standard in environmentally friendly materials. So, if there is more demand for vegan ‘leather’ products, more time and resources will be spent on innovation. If we support innovation and sustainable development, the fashion industry will move forward in a sustainable direction.
Let’s do this
We can imagine, that with this information you would like to take action right away and start using vegan leather instead of real leather. But where to find the right vegan leather for your product?
Some materials, like Piñatex® by Ananas Anam and MuskinTM by Life Materials are easy to order online and have much information available on their website. This is not the case for all however, and some manufacturers are so overwhelmed by all the enquiries that they are not taking any new requests. The Sustainability Club has mapped out all the bio-based leather alternatives that are available or in development. We also have swatches available in our Sustainable Fabric Library. You can contact us if you need advice, or if you would like us to help you to find the right vegan leather for your products.
Image by The Sustainability Club
Pulse of the Fashion Industry, Copenhagen Fashion Summit, 2017
Sustainable Material Guide, Modint, 2016
The True Cost, documentary, 2015
Circular Design sprint, Circular Fashion, 2020
Dioxins and their effects on human health, World Health Organization, 2016
PVC: The Poison Plastic, Greenpeace, 2013
Fashion’s long hunt for the perfect vegan leather, Vogue business, 2019