Vegan shoes are footwear made without any animal ingredients or byproducts, but while such shoes are billed as cruelty-free, are they really any better for the planet?

Shoes can be made with a variety of materials that come from animals, including leather, silk, fur and wool. However, most arguments over ethical footwear often focus on leather.

The environmental case for vegan leather is similar to eco-arguments for vegetarianism. Raising animals for their skin involves clearing trees for pastures, as well as energy-intensive feeding and the use of antibiotics that find their way into the food chain.

Animal hides must be chemically treated, or tanned, to prevent them from deteriorating. Chemicals such as hydrogen sulfide, ammonia and chromium are often used, and they can leach into soil and water in high enough levels to be carcinogenic.

Leather tanneries are ranked among the top 10 toxic-pollution problems worldwide by the New York's Blacksmith Institute, and the EPA has designated many former tanneries as Superfund sites. Overseas, the tanning industry has drawn concern from environmental groups and the United Nations, especially in developing countries.

However, synthetic leathers are often petroleum-based, and they also require toxic chemicals in production.

Some faux leathers are even made of polyvinyl chloride, or PVC, which contains phthalates, chemical additives linked to a variety of health problems.

Certain vegan leathers are cork- or kelp-based, and many mainstream leather alternatives are a blend of cotton and polyurethane. While polyurethane is far from eco-friendly, it’s less problematic than PVC.

But the question over what material makes the greenest footwear is more complicated than whether natural or synthetic materials are used.

"Natural fibers and synthetics have their own problems," Huantian Cao, a professor in the Department of Fashion and Apparel Studies at the University of Delaware, told Mother Jones.

One the one hand, petroleum is a depleting and polluting resource. However, on the other hand, producing materials like cotton involves using lots of water, as well as pesticides and fertilizers. Less than 1 percent of the world’s cotton is grown organically.

Still, some vegan shoe companies, such as Kailia, do use organic cotton. Others, like Cri de Couer, use materials like post-industrial polyester and reclaimed soles to make their footwear.

While many of the synthetic materials used to make vegan shoes are derived from petroleum, some companies have established closed-loop recycling programs that allow consumers to return worn-out shoes. Parts of those shoes are then used to create new ones.
 

"Recycled polyester, old tires and fishing nets can be reused through upcycling to create new eco-friendly shoes, said PETA manager Danielle Katz. "Synthetic materials can be directly produced and cut out to fit the exact needs of companies — without many leftovers like in the leather business."

However, according to The Vegetarian Site, vegan shoe companies often have production headquartered in Asia where little is known “about labor conditions or if the final product is truly vegan.”

The website encourages eco-conscious consumers to do their research and purchase vegan shoes made by retailers in countries with strong labor laws, such as the U.S. or Europe.

PETA maintains an updated list of companies that are either vegan or sell vegan shoes.

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