Potassium ferrocyanide . . .

I’m not a chemist, but this is what I dug up from the web:

Considered a harmful irritant chemical compound if ingested, inhaled, or applied to skin, and may cause serious injury, or death.

As with all things, this fact is heavily dependant upon concentration of the dose. Various poisons are used daily as common cures and treatments for different ailments, not the least of which is “small-dose” radiation therapy. Taken in moderation, X-ray therapy has been shown to be beneficial to the human body, while heavy doses are known to be lethal.

For spills involving potassium ferrocyanide, SCBA, or an MSHA approved respirator, and chemical suit is strongly recommended.

A yellow prussiate of potash, consisting of lemon-yellow monoclinic crystals or powder, it is soluble in water, and begins to lose crystal-water at 70 degrees C, becoming completely anhydrous at 100 degrees C. It can be decomposed into potassium cyanide when strongly incandesced and forms very toxic cyanide when combined with certain acid(s).

Potassium ferrocyanide is commonly used for the production of colorants, coatings, printer’s inks, and is used in metallurgy and pharmaceuticals.

"If this substance had been put in the water network it appears that it would not have been capable of causing any damage whatsoever," said Emilio del Mese, a government official.

Very true, however, I would have to say these folks were very likely up to no good, and chose potassium ferrocyanide as simply a “safe”-compound way to transport and store an otherwise highly toxic, potentially lethal chemical.

As with any news story, not all the facts are released, so we have no idea what true potential existed -- if any. Was there a certified, or at least competent, chemist in the suspected terrorist group, and did they have, or have the ability to obtain, the required elements that would transform a potassium ferrocyanide compound to a more pure, more dangerous form?

Dan