NOT Good stuff to eat (turns to hydrogen cyanide gas is the stomach from
HCL in there) or to breathe, but as an bottle of powder on a shelf, not
that bad. Potassium Cyanide as a solid isn't readily absorbed through
the skin nor cause systemic posioning from skin exposure.
Hydrogen Cyanide is the bad actor form of cyanide. When inhaled either
by hydrogen gas being present or formed from the acid reaction with
postassium cyanide is highly toxic. One of the worst industrial
poisining accidents on record is from a plating shop where in trying to
clean out the sludge from a plating tank containing cyanides, someone
poured a gallon of muriatic acid (concentrated HCL) into the tank. The
hydrogen bonded with the CN to form HCN or hydrogen cyanide and the
postassium and the chloride formed sodium-free salt.
Like almost all chemical compounds, it can be used safely, with knowledge
and the proper equipment.
Potassium ferricyanide is not the same bad actor potassium cyanide is and
needs less stringent precautions.
Howard Etkind
Etkindh@ucunix.san.uc.edu