JL, << HCN is the active ingredient is Zyklon B (and is a poison). >> Liza: >what is Zyklon B? Sorry for the typo. I meant: "HCN is the active ingredient in Zyklon B". Zyklon B is a gas that was used by the Nazis (and also an insecticide, I think). The other components of Zyklon B were just carrier substances; what actually killed was HCN. JL << Apricot kernels don't contain HCN, but its cyanogenic glycosides *release* HCN when in contact with the stomach acids. >> Liza >Thanks for the explanation. Do you happen to know the chemical formula for >this reaction? I don't... sorry. Best wishes, Jean-Louis [log in to unmask]