It seems like recently we’ve been enamored of leather, and with good reason. There are some wonderful new products appearing in the marketplace, all of which carry the important attributes that a designer wants when they specify leather over man-made or synthetic materials. We even saw something that would normally be regarded as offal turned into a higher-value product (rumen leather).
But leather is a commodity that is not without its detractors. Animal rights supporters, vegans, and others who believe that animals should not be slaughtered for human use are adamantly opposed to leather. Ecologists and environmentalists sometimes oppose leather, not only because of the substantial amount of pollutants and toxins the tanning process can produce, but also because leather has a substantial ecological footprint. They argue that land, which might be better used to grow crop plants, are instead sequestered to use for animal pasturage.
Of course, in dealing with these commodities, it’s never quite as simple as ‘yes leather’ or ‘no leather.’ Leather itself is a byproduct. Leather is created with a multi-step process from the skins or hides of animals. With the notable exceptions of animals grown for the fur industry or for upholstery, very few animals are grown specifically for their hides. Instead, their hides are byproducts of the much larger food industry.
Cattle, pigs and sheep are the primary animals grown for food purposes. The process of harvesting these animals for food purposes includes removing its skin. The hides of these animals are sold to tanners and the process of converting what would otherwise be waste biomass into something useful begins. Millions of animals are slaughtered every year for food (beef, pork, lamb/mutton); if their hides were not converted into useful products, it would be difficult to dispose of the waste in any ecologically sound fashion.
While it would be easy to suggest that if people would just stop consuming meat, then there would be no need to address what to do with all of the byproduct skins. That is a facile response to an obviously bigger issue. Suggesting that animal leather should be replaced with synthetic or man-made materials is also an overly simplistic answer. Man-made materials also carry a substantial carbon footprint, as most of these synthetics require extensive oil inputs with large multipliers (from initial feedstock to finished product). Additionally, synthetic materials rarely approach the overall qualities of animal leather that designers want for their finished products.
Unfortunately, given the reality of how animals are produced for consumption, there’s no real driving market force to develop new ways of synthesizing animal leather – after all, there is already a huge glut of skins in the marketplace. While the technology does exist to grow leather in vitro, it is expensive, and there’s no market basis to develop this technology into something that will enable huge amounts of leather to be vat-grown when so much animal leather already exists.
This is a pity, since leather that is synthesized from the molecular level would be uniformly thick throughout, have no scarring from living naturally, and could have precise attributes molecularly encoded during the growth phase. Moreover, many of the steps required to tan leather wouldn’t be necessary, including all the steps required to remove non-collagen molecules from the hide.
Animal skins will continue to be a byproduct of the world’s appetite for animal flesh. We therefore need to look at different ways of handling this byproduct that is less wasteful and less environmentally harmful.