The humble flip-flop is the world’s most popular shoe.
About 3 billion new pairs of these little plastic sandals are made globally every year. Eventually, they wind up as non-biodegradable trash in landfills, rivers and oceans.
It’s a surprisingly big environmental footprint for something that seems so inconsequential.
“One of the largest pollutants in the ocean is polyurethane from flip-flops and other shoes that have been washed or thrown into rivers and flow into the ocean,” says Stephen Mayfield, a UC San Diego professor of biology.
Mayfield, along with chemist Skip Pomeroy and their students at UC San Diego, may have found a solution.
Building on their earlier success in using algae oil to make the world’s first sustainable surfboard, they’ve developed a process that transforms algae oil into a flexible foam that can be fashioned into footwear. The result is Triton Soles, a flexible yet durable flip-flop adorned with a trident logo and a simple strap.
Mayfield, Pomeroy and fellow professor Michael Burkart plan to scale their algae innovations through a startup company, Algenesis Materials, which employs some of their lab students and provides them with the opportunity to experience what Pomeroy calls “project-based learning.”
“Our plan is that in the next year, you’ll be able to go into the store and buy a flip-flop that is sustainable, biodegradable and invented by students at UC San Diego,” Mayfield said.
How it works:
The Triton flip-flops, shoe soles and other polyurethane products the scientists make from living algae oil are “sustainable” because the carbon to construct them was pulled from the atmosphere, rather than underground oil reserves. And, says Mayfield, the flip-flops are 100 percent biodegradable (a first!). They'll degrade in a compost pile in about three months.