Vegetable Tanned Leather vs. Vegan Leather

Vegetable tanned leather and vegan leather may sound similar, however, the two terms don’t overlap in the same way they do in reference to one’s diet. Vegetable tanning is the process of turning an animal hide into leather by treating the hide with natural tannins derived from trees. Our vegetable tanned leather is made using tannins from Quebracho and Mimosa trees, both of which are native to the Andean region. Check out our write up on vegetable tanned leather to learn more about the history and craft behind the process. At Alta Andina, we start with high-quality cowhides, which have fewer marks and scratches than cheap cowhides, and use only full grain leather. Our naturally dyed, full grain, vegetable tanned leather is safe for the environment, leatherworkers, and you––our clients. Vegan leather, on the other hand, is made from materials other than animal hides. A majority of vegan leather is made from polyurethane, which has its fair share of negative environmental externalities and effects on human health. However, vegan leather can also be plant based. Exciting developments have recently been made in the areas of mycelium leather and cactus leather. 

Cactus leather

Plant Based Vegan Leather: Mycelium & Cactus Leathers

Mycelium leather is a material that has been grown from mycelium cells to resemble leather. Mycelium is the vegetative body of the fungus, the threads that branch out under soil, and can produce mushrooms. The interwoven threads of the mycelium grow in a way that emulates its natural root system underground. The threads produce a web-like structure that also resembles the fibers of cowhide leather, which run from the corium, through the junction, and up to the outer grain. On cowhide leather, these fibers are most tightly woven at the grain, which is why the grain gives leather its strength and durability. Our full grain leather leaves the grain untouched, protecting the integrity of the leather. Read about what sets our full grain leather apart, and what some companies do to make their cheap leather appear high-quality. 

Mycelium Leather

Mycelium leather derives its strength in other ways. It produces a mycelial mat made up of its own interwoven threads. By growing mycelium leather in a lab, many factors can be manipulated to create a specific texture, thickness, or size of the mat itself. Thus, it has a more durable, rigid, and leather-like feel than other plant based or synthetic leathers. Moreover, with so many species of fungus, there are seemingly endless possibilities for the specific qualities and attributes of a mycelial mat. The mycelial mat, like a cowhide, must be tanned to produce leather. However, companies are keeping the methods of their treatment processes proprietary, so the impacts are largely unknown. While mycelium leather is a more sustainable alternative to polyurethane leather, it has been noted that “some of the industry are cheating a bit because they incorporate a felted polyester and make it into a composite leather.” (10) Incorporating polyester into mycelium leather greatly adds to its environmental footprint, as polyester is one of the leading contributors to microplastic pollution. Read our blog post on microplastic pollution, or what we’ve dubbed The Synthetic Epidemic.

Cactus Leather

Cactus leather is another sustainable, plant based alternative to cowhide leather. The cactus plant is a particularly sustainable crop as it can be grown using only rainfall, without any additional irrigation. Moreover, leaves are removed from the plant when they are ready to be processed, and grow back in a matter of months, creating a continual cycle of harvesting without replanting. The cactus plant can produce for as long as a decade before it dies and needs to be replaced. Once the leaves are harvested, they must be dried before processing, which can be done in the sun naturally. When treated, cactus leather has a soft, malleable texture, but can easily rip or tear as a result. Cactus leather does not serve as a replacement for vegetable tanned leather because it lacks the strength and longevity. However, it provides a sustainable alternative to chrome tanned and polyurethane leathers, as both are already weaker materials. The chrome tanning process starts with a cowhide, and after tanning, becomes formless and floppy. Polyurethane leather is thin and malleable, and also lacks any rigid form. Thus, cactus leather serves as the perfect sustainable replacement as it is free of the toxic chemicals associated with the nefarious industries of chrome tanned and polyurethane leathers.

Synthetic Vegan Leather: Polyurethane Leather

Polyurethane leather, often referred to as “pu leather” is so prevalent in the leather sector these days that a search for leather coasters will yield as many products made with pu leather as cowhide leather. Companies intentionally try to confuse their consumers with terms like “genuine pu leather,” blurring the lines as much as possible between their product and an actual leather product. The low cost of pu leather items provides much of their appeal—the price of polyurethane leather is cheap, too cheap. The true cost of producing polyurethane leather is not quantifiable without considering its degradation of our environment, and its adverse health effects. 

Polyurethane leather originates from fossil fuels, as oil is the base of plastics and synthetic materials like polyurethane. A myriad of chemicals are added to oil in order to achieve the specific tactile qualities of the desired synthetic material or plastic. Phthalates, for example, are used to give plastics their elasticity and strength. Phthalates have an alarming effect on human health. We absorb phthalates from the plastics around us. Common plastic packing for food and drink containers can contain phthalates that leach these chemicals into what we eat and drink. It has also been found that we absorb phthalates by breathing air that contains particulate matter of the dangerous chemical. Phthalates are endocrine disruptors, which are linked to different types of cancer, obesity, and impacts on male fertility. Moreover, phthalates are passed from mother to child in the womb, crossing the placenta. As shocking as that list is, it hardly does justice to the scope of the problem. 

While polyurethane leather has qualities such as its resistance to water that some tout, we’re strongly opposed to propping up polyurethane leather for many reasons. Primarily, polyurethane is a petroleum product, and in order to combat climate change, our reliance on fossil fuels must change. Our fossil fuel dependence includes the excessive global use of plastics. The chemicals used to make plastics, and specifically the chemicals used to make polyurethane, are a threat to human health and the environment. 

Our Bottom Line

At Alta Andina, we don’t use virgin plastics in our supply chain, or in our products, or our packaging. We do however utilize recycled plastic in our eco-friendly pouches, which are made by weaving together recycled plastic thread and upcycled cotton. Our vegetable tanned leather is safe for the environment, and free of the hazardous chemicals and fossil fuel derivatives used to make chrome tanned leather and synthetic polyurethane leather. Using sustainable materials and limiting our sourcing and manufacturing to the Andean region means that we can reduce the environmental impact of our products through both transportation, and production. We’re excited about the potential of plant based leathers, and are actively working to incorporate them into our ethical and sustainable supply chain, based entirely in the Andes. 

Sources

1. https://desserto.com.mx/home
2. https://www.osha.gov/SLTC/isocyanates/
3. https://www.nytimes.com/2017/08/16/health/male-sperm-count-problem.html
4. https://www.vogue.com/article/reishi-launch-vegan-sustainable-faux-leather-alternative
5. https://www.bbc.com/news/business-49550263
6. https://www.mycoworks.com/
7. https://boltthreads.com/technology/mylo/
8. https://www.fastcompany.com/40562633/this-leather-is-made-from-mushrooms-not-cows
9. https://sustainablebrands.com/read/chemistry-materials-packaging/how-gap-mycoworks-thousand-fell-are-edging-fashion-closer-to-circularity
10. https://www.nytimes.com/2020/09/16/science/fungus-leather.html?referringSource=articleShare
11. https://www.cdc.gov/biomonitoring/Phthalates_FactSheet.html#:~:text=Phthalates%20are%20a%20group%20of,dissolving%20agents)
12. https://www.niehs.nih.gov/research/supported/assets/docs/j_q/phthalates_the_everywhere_chemical_handout_508.pdf
13. https://www.niehs.nih.gov/research/supported/translational/peph/podcasts/2015/mar23_phthalates/index.cfm