I have been using Corn Cob Litter for almost two years now - and I do not
see any reason that someone would think it is bad for the ferrets' sinuses.
I pour it into the litter boxes and it doesn't raise any dust (unlike cat
litter).  It is absorbent, the "smell" factor is way down, it is reasonably
priced, etc.  I do know they make scented and "natural" varieties - I use
the natural as I have allergies to scents.  In the entire time I have used
this my ferrets have never had sinus problems of any kind.  If there really
is a problem with it I would like to hear of personal experience or a
study, rather than just a blanket statement by someone that it is bad.
 
Karla
Meep and Daisy
[Posted in FML issue 2942]