I know that their so called "bamboo" fabric is not bamboo at all. It is RAYON from bamboo. This means the mill made rayon from processing the bamboo tree and in the end there is NO bamboo left in the final product. This manufacturing practice is extremely toxic to our environment. I refuse to buy rayon from bamboo because of this.
Rayon is considered a hybrid material. It falls between natural and synthetic. There is other vegetation used to make rayon (other forms of it) as well but I am not familiar with that process or toxicity.
For more information about RAYON and how it came to be visit:
swicofil dot com/viscose
The history behind it and how it got the name "rayon"...very interesting read.