This is the only reference I could find on CS toxicity to brain cells.  If this 
is true then do not use DMSO with CS.  It will carry it right across the blood 
brain barrier within seconds of oral or topical administration.    

If anyone has any information on this subject it would be of great help on this 
list.
Thanks....direct replies also appreciated..

 http://colloidalsilver.hypermart.net/silver/faq.html

> Silver can be toxic to nerve cells in the brain and spinal cord, but
> is normally prevented from entering those areas by the blood-brain
> barrier.