The msds sheets show propylene glycol as much less toxic than ethylene glycol:

http://www.jtbaker.com/cgi-bin/msds-s.pl?searchdata=L715
http://www.jtbaker.com/msds/p6928.htm

Marshall

BROOKS BRADLEY wrote:

>                         Dear Yvonne,
>                     Are you SURE you want to include this glycol-based
> compound in a medical protocol that would introduce it into the body
> systems?
> In animal experiments, ethylene glycol has demonstated to be quite
> lethal....and I am informed that the propylene-derivative is not far
> behind.  These compounds have the capability of causing complete renal
> shutdown--- in canines---especially.....and I suspect in humans as well.
> There is NO known antidote for expressing "antifreeze poisoning" of this
> type.  In fact, heartless "dog poisoners" have used this heinous method for
> killing many innocent pets in the past.  Dogs will readily consume this
> substance....especially because of its pronounced sweet taste.  I would
> advise you to thoroughly research this matter before introducing propylene
> glycol into the body-----either topically or internally.
>                                 Just a caution.  Sincerely,  Brooks Bradley.
>
> Yvonne and Mickey - BIO-SIL wrote:
>
> > Hi all!
> >
> > I've been asked a question which I cannot answer.  Can anyone assist me
> > please?
> >
> > .. and the question is:
> > Can one mix Colloidal Silver with propylene glycol??
> >
> > Many thanks!
> > Yvonne :o)
> >
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