What is the Sustainably Sourced Knit version made from and does it have any harmful materials?

The Sustainably Sourced Knit version is made with 100% Tencel™ Lyocell fibers. As with all Ergobaby products, the materials used in production are carefully sourced and thoroughly tested to be free of potentially harmful substances. Additionally, the fabric of the Sustainably Sourced Knit version is Oeko-Tex Standard 100 Certified and is safe for babies. To attain Oeko-Tex Standard 100 certification, the fabric has been tested and certified to be free from harmful levels of more than 100 substances known to be harmful to human health.