Changing Markets new report Spinning Greenwash: How the fashion industry’s shift to recycled polyester is worsening microplastic pollution reveals that recycled polyester generates 55% more microplastic particles during washing than virgin polyester, which is less brittle. These particles are also nearly 20% smaller, allowing them to travel more widely through the environment and pose greater risks. A single laundry cycle can release up to 900,000 microplastic fibres, and once they’re in the environment, they become one of the most pervasive forms of pollution—contaminating soil, air, water, wildlife, and even human organs.

The study of 51 garments from five major brands, includes T-shirts, tops, dresses and shorts sold by Adidas, H&M, Nike, Shein and Zara. The study is the first to compare brands for microplastic pollution, Changing Markets believes.