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Re: to squabble or not..

At 10:14 PM 04/09/2001 +0000, you wrote:
>I got the same thing Richard.
>R.
  Mark answered this already.
  I don't want to further this issue. A book I've found helpful in
understanding chemical hazards is_The Dose Makes the Poison_ 2nd ed.
M.Alice Ottoboni, Phd., 1991, Van Nostrand Reinhold  ISBN 0-422-00660-8
While it does not discuss the hazards of specific chemicals it does give
some guidance as to how to evaluate hazards.
  I have not found a good, reliable, source of specific hazard information.
MSDS are often aimed at industrial users.
  Obviously some sustances used in alternative photography must be handled
with extreme care. Even in conventional photography there are some
compounds which are hazardous if handled carelessly. It would be useful to
have a source of factual information. That would help in deciding if some
substance was really just too hazardous to take a chance on. 
  I am convinced that Mercury and mercury compounds fall into this
catagory. It is also obvious (or should be) that concentrated acid, of any
sort, is very hazardous and should handled with specific precaucations and
very great respect. There are some acids, maybe Hydroflouric, which are
probably too hazardous for a home lab.
 I am not sure where Potassium dichromate fits in here. It is obviously
hazardous, but it is also at the heart of several alternative processes.
 I suspect that warnings are in order but that they should be accompiannied
by some realistic assesment of the hazard and practical advise as to how to
deal with it. The sort of warning which makes you feel that a small bottle
in the next county is reason to run for the hills is not very helpful. 
  Bob Maxey may be right about dichromate, I'm far from an expert and can't
argue the point. I would like to know, however, just what sort of
precautions I would have to take to use the stuff safely if I wanted to
try, say, gum printing or carbon printing or some other process which
depends on dichromate sensitizing. If his warnings are valid there is
excellent reason to stay away from the stuff. 
  
----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com