UC San Diego hopes to stomp out plastic pollution with these $135 shoes made from algae

Stephen Mayfield has explored replacing petroleum products with algae-based concoctions for two decades, having suffered a previous setback with efforts to engineer biofuels.

Now the longtime UC San Diego scientist believes he may finally have a recipe for success with a new line of biodegradable shoes. The endeavor, equal parts chemistry and capitalism, isn’t only about selling eco-friendly footwear.

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The 66-year-old biochemist’s ultimate goal is perfecting and popularizing his patented polyurethane foams made from genetically engineered algae. He hopes his petroleum substitute will eventually be used in everything from the cushions in car seats to waterproof jackets and travel bags, perhaps even, one day, car tires.

While such products are technically feasible today, making something that’s competitive in a consumer market is the real trick, he explains. He said numerous companies, most notably the Carlsbad-based Reef sandals, have recently started to express interest in adopting his new technology.

“That’s the little victory if I sell shoes,” Mayfield said. “The big victory is if everybody on the planet who sells shoes has to use this material.”

Mayfield launched his footwear line, Blueview, this spring. The endeavor is the result of more than six years of research backed by an enthusiastic team of academics and investors.

The group has shown in recently published studies that the casual loafers — made with hemp, eucalyptus yarn and plant-based soles — will break down not only in compost piles but in the ocean. They found that out, in part, by immersing several shoes under the Scripps Pier for months at a time.

Blueview shoes been have shown to biodegrade within a year on land or two years in the ocean.

Blueview shoes, on display at UC San Diego, been have shown to biodegrade within a year on land or two years in the ocean.

(John Gastaldo/For The San Diego Union-Tribune)

The most recent findings, published September in the journal Science of the Total Environment, are “exciting,” said Katrina Knauer, a leading researcher at the National Renewable Energy Laboratory in Denver.

“Many argue that imparting biodegradability to materials such as polyurethane shoes will promote littering and that we should only be designing for recyclability,” Knauer said. “However, even if we have a perfect recycling infrastructure, we would still experience loss of plastic materials to the natural environment due to the inherent lightweight, small-format nature of these materials and, let’s face it, human behavior.”

Such breakthroughs are only the beginning for Mayfield. His research company Algenesis Materials is increasingly focused on making consumer-grade foams that not only quickly biodegrade but thrive in an industrial setting.

Blueview’s manufacturing is done in Indonesia, where profitability is measured in minutes. If a foam takes too long to set in a mold, it doesn’t matter how good it is for the environment. It won’t be cost-competitive.

Right now, Mayfield said his foam is about 35 percent more expensive than petroleum-based equivalents. However, soles are only a small factor in the overall cost of his shoes, which retail for $135 a pair. Researchers said the shoes should last as long as a traditional sneaker, from two to four years on average.

“We specifically picked a market where we knew we could get entry, where we wouldn’t price ourselves out,” he said.

Research continued Thursday morning at UC San Diego’s Applied Physics and Mathematics building, where Mayfield’s employees tested mixtures of algae to create different foam variations. In one room, bright green liquids swirled under fluorescent lights in glass beakers sitting on motorized, gyrating platforms.

“This is the raw material,” Mayfield smiled, kneeling down to admire the samples. “All of these guys we’ve engineered to make one component or another of our polyurethanes.”

Gordy Scofield, polymer engineer for Algenesis, works on making algae-based foams in a lab at UC San Diego on Sept. 29, 2022.

Gordy Scofield, polymer engineer for Algenesis, works on making biodegradable, algae-based foams in a lab at UC San Diego.

(John Gastaldo/For The San Diego Union-Tribune)

Across the hall, Gordy Scofield, a former UC San Diego master’s student-turned-polymer engineer for Algenesis, timed a mixture to see how quickly it would congeal into a foam.

“I’m testing how fast it reacts, how fast it could be pulled out of a mold in a production setting,” explained the 27-year-old, wearing a white lab coat, his long hair in a bun.

Mayfield watched over Scofield’s shoulder, narrating with a practiced mix of technical jargon and folksy salesmanship. He said the polyurethane foam, while completely biodegradable, still requires the use of some petroleum-based ingredients, something they hope to remedy in coming years.

“Gordy is a cook,” he said excitedly, “a plastics chef. You have two basic things, an isocyanate and polyol. Flour and eggs. How many things can you make with that? Hundreds.”

Then Mayfield abruptly excused himself for a meeting between the company’s investors and its marketing team. “This is going to be a duke out,” he chuckled, slipping out the door.

Stephen Mayfield has created biodegradable shoes made from plant-based polyurethane foams.

Stephen Mayfield wears a pair of his biodegradable shoes made from plant-based polyurethane foams.

(John Gastaldo/For The San Diego Union-Tribune)

Mayfield has lots of practice balancing science and commercial pursuits.

He and several colleagues launched an effort in 2007 to create biofuels from algae under the name Sapphire Energy. The project attracted more than $100 million from investors, such as Bill Gates. The company employed about 150 people at its peak, selling green crude oil to a refinery in Texas.

However, biofuels never proved economically competitive with conventional petroleum, especially after the U.S. fracking boom started producing a flood of cheap oil and gas.

“Around 2014, when the price of oil tanked, we saw that we needed to make other co-products,” said Ryan Simkovsky, a biologist and vice president of scientific affairs for Algenesis. “One of the biggest polluting industries out there is the fashion industry, so we wanted to make an impact in that way.”

Mayfield’s most recent scientific paper notes that about 17.6 billion pounds of plastic enter the ocean every year. That’s resulted in trash gyres, such as the 618,000-square-mile Great Pacific Garbage Patch. It’s also led to the proliferation of toxic microplastics that have shown up in everything from fish to human blood.

The negative impacts of plastic production are well documented. Pollution produced while drilling and refining petroleum not only are warming the planet but also have been linked to cardiovascular disease, respiratory conditions and cancer.

The Washington D.C.-based Plastics Industry Association did not return a request for comment for this story.

In the last half-century, humans have created a whopping 6.6 billion tons of plastic waste, according to a 2017 paper from UC San Barbara published in the journal Science Advances. Only about 21 percent has been recycled or incinerated, the other 79 percent ending up in landfills or natural environments such as the ocean.

Mayfield has seen such pollution firsthand while surfing in the Maldives several years ago. On the coral islands off the coast of India, he repeatedly found beaches covered in used plastic bottles and old flip-flops. He said that experience helped motivate his most recent endeavor.

“Every single island we pulled up to, without exception, the beaches were covered with plastic stuff,” he said. “I was like, ‘How sad is that?’ Look what we’ve done to this planet.”

Much of the research in the United States on reducing plastic pollution has in recent years focused on how to replace or recycle single-use plastic bags. But Mayfield said much of those efforts are still a decade from being economically viable, and he wanted to have a more immediate impact.

“We just decided that was shoes,” he said. “If we could make compostable, biodegradable shoes that would actually do something for the planet.”

Mayfield believes that if he can prove his foam is cost-competitive with petroleum products, eventually the private sector will feel pressure from consumers and perhaps lawmakers to help spur future innovations.

“Let’s start with something that doesn’t bankrupt us and then work to solve the bigger problem,” he said.