- The lack of sustainability of animal leather has been a hot topic for the fashion industry, bringing more eco-friendly natural alternatives into the limelight.
- The main advantage is the efficiency of growing mushrooms – they do not require light, they convert waste into useful materials and store carbon through accumulating it in the fungus.
- Going from a single spore to a finished “fungi leather” product takes a couple of weeks, compared with years required to raise a cow to maturity.
Seven millennia since its invention, leather remains one of the most durable and versatile natural materials. However, some consumers question the ethical ramifications and environmental sustainability of wearing products sourced from animals.
This shift in social standards is the main reason we’re seeing a wave of synthetic substitutes heading for the market.
But these materials face the same disposal issues as any synthetic plastic. So, the leather market has begun to look to other innovations. As strange as it might sound, the latest contender is the humble fungus.
Research by my colleagues and I, published today in Nature Sustainability, investigates the history, manufacturing processes, cost, sustainability and material properties of fungus-derived renewable leather substitutes – comparing them to animal and synthetic leathers.
Have you read?
- This watchmaker uses mushrooms to make leather watches
- These facts show how unsustainable the fashion industry is
How unsustainable is animal leather, actually?
How sustainable leather is depends on how you look at it. As it uses animal skins, typically from cows, leather production is correlated with animal farming. Making it also requires environmentally toxic chemicals.
The livestock sector’s sustainability issues are well known. According to the United Nations Food and Agriculture Organisation, the sector is responsible for about 14% of all greenhouse emissions from human activity. Cattle rearing alone represents about 65% of those emissions.
Still, it’s worth noting the main product of cattle rearing is meat, not leather. Cow hides account for just 5-10% of the market value of a cow and about 7% of the animal’s weight.
There’s also no proven correlation between the demand for red meat and leather. So a reduction in the demand for leather may have no effect on the number of animals slaughtered for meat.
That said, leather tanning is still energy- and resource-intensive and produces a lot of sludge waste during processing.
This gives leather a higher environmental impact than other minimally processed animal products such as blood, heads and organs (which can be sold as meat products or animal feed).
From spore to mat
These technologies take advantage of the root-like structure of mushrooms, called mycelium, which contains the same polymer found in crab shells.
When mushroom roots are grown on sawdust or agricultural waste, they form a thick mat that can then be treated to resemble leather.
Because it’s the roots and not the mushrooms being used, this natural biological process can be carried out anywhere. It does not require light, converts waste into useful materials and stores carbon by accumulating it in the growing fungus.
Going from a single spore to a finished “fungi leather” (or “mycelium leather”) product takes a couple of weeks, compared with years required to raise a cow to maturity.
Mild acids, alcohols and dyes are typically used to modify the fungal material, which is then compressed, dried and embossed.
The process is quite simple and can be completed with minimal equipment and resources by artisans. It can also be industrially scaled for mass production. The final product looks and feels like animal leather and has similar durability.
To continue reading the full article from the World Economic Forum click HERE