All our materials respect the environment, and all our cotton products use organic cotton. However, some of our products are made using wood pulp fibres such as Modal and Tencel. For some of our products, we also use recycled polyester. These products are certified OCS Blended when they are mixed with organic cotton. However, when they are used 100% in the product, they are not certified because there is no certifying body for these materials. You can find all of these certifications on each product sheet.