Polyester, nylon, acrylic and other synthetic fibers—all plastic byproducts—make up 60% of the materials used in clothing. Even if wearers aren’t tossing their shirts or pants into the ocean when they’re done with them, the plastics in our clothing still make their way there. With each wash, fibers shed from the clothing and are drained through waterways into the ocean. “Think about how many people are washing their clothes on a daily basis, and how many clothes we all have,” says Imogen Napper, a marine scientist at the University of Plymouth. A study she co-authored found that individuals generate 793 pounds of shed plastic throughout the year. “A large proportion will get caught by the sewage treatment works, [but] even that small proportion that does fall through is going to accumulate,” she continues. Read more about the issue on Vox.