Shoes That Could Help Save the World

The shoe industry has a big carbon footprint, thanks in part to the fact that many shoe parts—including plastic soles, logos and shoelace tips—are made from petroleum. Retail startup Allbirds is testing an eco-friendly alternative: SweetFoam, a new material made from parts of sugarcane that would otherwise be discarded (thereby releasing climate change–causing carbon dioxide into the air). Allbirds launched SweetFoam earlier this year in a line of flip-flops; it plans to start using the material across its entire product line soon—including its popular wool sneakers, which have sold more than 1 million pairs since their 2016 debut. And in an effort to encourage its competitors to follow suit, the San Francisco–based company has made the technical know-how behind SweetFoam “available to anyone who wants it, without question,” says co-founder Joey Zwillinger. —Justin Worland