Hey there,
Good call on leaving it on the floor. I had it up on a shelf,
consequently right next to a heating vent. That could have been a very
steamy situation.
Yerba mate, as far as I have experienced, is just a type of green tea,
big with indigenous populations in South America. It is considered
somewhat of a stimulant, in that it has as much caffeine as other
green teas. But the antioxidants are said to be good for vitality, so
many know it as a tonic and drink it religiously. That is the first I
have heard of the "carcinogen thing", but usually Wiki is at least
somewhat on point. Perhaps I will re-think using it as the base of my
'bucha.
If my SCOBY grows, it's first baby will have your name on it. : )