Adidas is one of the busiest shoemakers in the world, manufacturing over 400 million pairs per year.

It should come as no surprise that making that many shoes requires some serious resources. Fortunately, Adidas is turning to a source of copious materials for their shoes: plastic, much of which is floating around in our oceans.

Constantly creating new materials for shoes is certainly bad for the environment. However, recycling plastic that made it into the oceans is a great way to mitigate the damage caused by manufacturing while removing a seriously harmful substance from the ocean. Experts are predicting that in just three decades, there will be more plastic in the oceans than fish. Plastics are already wreaking havoc on marine life across the globe, with one study estimating that 90% of seabirds have consumed plastic waste. This plastic is harmful to both marine life and humans, both of which rely on the ocean. This is why Adidas partnered with Parley for the Oceans in 2015 with the goal of turning plastic waste that kills birds and marine animals into footwear. Since the partnership started four years ago, Adidas has made real progress. In 2019, Adidas expects to make 11 million pairs of shoes using recycled plastic.

So, how does Adidas actually stop plastic from reaching the ocean? First, Parley for the Oceans and their partners collect plastic trash from coastal areas. After the trash is sorted, plastics are sent to an Adidas processing plant, where they use the parts they can, mainly plastic bottles that contain polyethylene terephthalate (PET). All the plastics that Adidas can’t use are sent to a normal recycling facility. Once the plastics are sorted, Adidas crushes, washes and dehydrates the plastic until there’s nothing but little plastic flakes. These flakes are then heated, dried, and cooled before being cut into resin pellets. These pellets are melted to create a filament, spun into “ocean plastic.” This is the material that Adidas can use to form the upper parts of their shoes, as well as other products like jerseys.