Contact Baryshnikov, yes the famous Dancer.
His activerwear brand of Organic cottons set the standard a few years back, perhaps they can give you some good leads and info about it.
He did mostly t-shirts, tanks, draw cord pants and shorts. Not Cheap. $$$$
HERE IS THE LABEL (no i'm not a label collector...lol)
Yes, more and more people are going to want to "go green". Target stores are even going to quit selling vinyl items.
Vinyl is so toxic.
check it out at wikipedia