Sneakers have quickly become a fashion staple. For some, sneakers are a lifestyle. For others, sneakers are purely for comfort and protection. However, despite the aesthetic of the sneaker, most shoes in the market are not biodegradable and made from materials like ethylene vinyl acetate, also known as EVA.

The shoe industry discovered the soft, flexible foam during the running boom in the early 1970s. Quickly after, EVA foam revolutionized the midsoles of runners' shoes, and was highly regarded for its buoyancy, waterproof resistance and ability to protect runners’ joints against impact.

Once EVA was introduced in the runners footwear market, the foam quickly gained popularity. According to Sneaker Factory, EVA midsoles are the most common in the industry, especially in athleisure footwear.

Despite EVA’s popularity, the industry has been grappling with ways to be more sustainable. In a study conducted by Aston Baby, 39% of companies in the shoe manufacturing industry had started implementing, or already had, a sustainability program set in place in 2019. The following year, in 2020, that number increased to 44%.

Shoe designer Micheal Weyrauch has worked in the footwear industry for over 10 years with companies such as Converse, Nike and Clarks. He understands the need to use more sustainable materials in shoe designs but admits it will be a difficult transition for companies to let go of EVA.

“Once you see the scale of the business and of the manufacturing and the way they've been doing it for 25, 30 years, 40 years, no one wants to change that,” says Weyrauch. “And it takes a huge investment to change all that, and who's going to invest in that, you know?”

Although EVA isn’t the only material that can be used to design shoes, it is the most popular thanks to its shock-absorbing abilities and for the level of comfort it provides consumers. According to Plastic Insights, EVA sales have increased worldwide by 2.67 billion dollars since 2015 and sales are only expected to grow.

Investing in sustainability efforts can be tricky for manufacturers. According to a US Consumer Sustainability Survey in 2019, 62% of consumers were making purchases based on price point. However, over 20% of Gen Z consumers would rather purchase sustainably despite price point.

“Yeah, the ideas are there,” Weyrauch says. “The willingness to give up, the old way of developing products and engineering products is not there.”

Researcher Otávio Bianchi, Professor at the Federal University of Rio Grande do Sul in Brazil, specializes in EVA research. He agrees that there is a lack of interest in companies shifting their focus to more sustainable practices. “What amazes me is that in the companies I visited, nothing is done because the soles are cheap,” said Bianchi. “Deep down, wearing shoes in this way does not generate a circular economy.”

According to Bianchi, despite EVA being non-biodegradable, companies can opt to recycle the EVA insoles by mechanically grinding the EVA material, then reusing the pellets that it spits out.

Companies like Nike have already started mechanically grinding rubber, EVA foam and end of life shoes. On their website, they breakdown the materials being recycled, how those materials are separated and howthey are repurposing the recycled materials. According to Nike, 130 million pounds of Nike Grind material have been recycled to date.

Los Angeles Times senior feature writer and shoe enthusiast Adam Tschorn owns 80 pairs of Vans. Over the pandemic Tschorn, who frequently covers fashion sustainability, bought a pair of the Nike Space Hippies.

“The twice a year fashion cycle has become four times a year, and it's like, buy more and more and more,” says Tschorn. “And so, the big problem is that everything about fashion is predicated on using up resources.”

Major shoe manufacturers like Nike, Adidas and Yeezy are leading the way when it comes to sustainability. Yeezy released its popular slip-on foam runner made from repurposed EVA and algae material. Nike released the Space Hippie sneaker made from all recycled materials and Adidas has been manufacturing shoes from recycled ocean plastic. Despite prominent sneaker brands making a push for sustainable practices, the use of EVA material is still prominent throughout the industry. Manufacturers find it challenging to find sustainable practices that work with their business models.

“Working on innovation teams, you know, big companies want to deal in the billions, maybe the high millions, but in the billions,” Weyrauch says. “So if it's not at that scale, they're not going to pursue it, because the dollars and cents aren't there. So it's chasing the dollar.”

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Manufacturing a sustainable shoe without material like EVA foam can be difficult on both the aesthetics and performance front. With steep price points on sustainable midsole material, manufacturers struggle to deliver a product that checks off sustainability, performance and aesthetics.

“The hand feel has to be there to hold the value of $150, right? Shoes are now $150 to $200,” Weyrauch says. “So if you feel like you're spending that money, and it doesn't feel like it [or like a high quality shoe], you're going to revert back to EVA.”

The Space Hippie is Nike’s attempt at reinventing sustainability footwear by using ground up EVA foam material. According to the Nike website, the Space Hippie was designed with a combination of 2% Nike grind rubber and foam materials, and retails at $224.

For Tschorn, the Space Hippie doesn’t feel any different from any other Nike shoe he owns. However, he wonders if companies who are deciding to move in a more sustainable direction are truly concerned about the impacts of non-biodegradable products like EVA or are being influenced by profit.

According to Statista, in 2018 the athletic footwear industry generated 16.55 billion dollars making the United States the leading footwear industry in the world.

“If we all really cared about the planet, we would only have one pair of shoes, one outfit, and you know we would wear it until it was threadbare,” Tschorn says. “But it is as much, if not more, in my opinion, a business decision than it is a pure save the planet move.”

The conversation in the shoe industry to pivot from materials like EVA is happening. However, the urgency to pivot into a fully sustainable industry is lacking. On average, Americans throw away 300 million shoes a year, according to the US Department of the Interior, which later results in millions of shoes out in landfills.

“I'm not trying to be cynical,” Tschorn says. “It's laudable and we only have one planet so far to live on, but I think they're moving perhaps quicker as a result of business, bottom line business, as much as to save the planet.”