GOTS is a standard most companies are using to show their products are free from toxic chemicals. The problem is this standard does allow 10% synthetic in the products.

Here is the standard https://www.global-standard.org/images/GOTS_Documents/GOTS_Standard_5.0_EN.pdf

Only textile products that contain a minimum of 70% organic fibers can become GOTS certified. All chemical inputs such as dyestuffs and auxiliaries used must meet certain environmental and toxicological criteria.

I think this is a garbage standard. It means it is better than synthetic but certainly not organic in my mind. 

Go to 2.4.15 and you see all the chemicals allowed in this "organic" fiber. 

So we prefer actual test results that have no synthetic chemicals.