Leather as we know it today, uses as tanning agents, heavy metals (such as chrome, aluminum, titanium, zirconium), glutaraldehyde, phosphonium, or in a more classic way, vegetable tannins. The global technological evolution run at a frenetic level in every sector; every single minute in the world, is born a new idea to improve the conditions of human existence and by consequence the health of the planet.
It is unimaginable that leather should not follow the same technological development, since it is a product of natural origin: