The Poisoner's Handbook by Deborah Blum Page A

assistant medical examiners in the Brooklyn office did an autopsy. It hinted at cyanide, which was known to cause a kind of chemical suffocation and would explain the blue look of oxygen deprivation. But cyanide from where? It killed quickly, too quickly for them to have imbibed it elsewhere and then strolled back home. Police searched the apartment again, once more failing to find a trace of the poison.
    “Mr. and Mrs. Jackson met their deaths by poisoning, but whether the drug was self-administered or sent to them is impossible just now to determine,” the medical examiner’s office announced. “The poison might have been administered in food or drink.” The doctor conducting the autopsy had removed both stomachs, placed them in specimen jars, and sent them from Brooklyn to Manhattan for analysis in Gettler’s laboratory. Until those results came in, investigators could “not determine what caused the death of the couple.”
    But, truth to tell, they rather hoped it was something else, something less ugly than cyanide.
     
     
    CYANIDES POSSESS a uniquely long, dark history, probably because they grow so bountifully around us.
    They flavor the leaves of the yew tree, the flowers of the cherry laurel, the kernels of peach and apricot pits, and the fat pale crunch of bitter almonds. They ooze in secretions of arthropods like millipedes, weave a toxic thread through cyanobacteria, massed in the floating blue-green algae along the edges of the murkier ponds and lakes, and live in plants threaded through forests and fields.
    Humans recognized early the murderous potential of cyanide-rich plants. Scholars have found references to “death by peach” in Egyptian hieroglyphics, leading them to believe that those long-ago dynasties carried out cyanide executions, perhaps by making a potion from poisonous fruit pits. Centuries later cyanide became more readily available in large and lethal quantities. That happened, in part, due to some experiments by a German painter who in 1704 was only trying to improve the colors on his palette.
    The artist, one Heinrich Diesbach, was a born experimenter. He spent hours in the laboratory of a Berlin chemist, trying to create a new shade of red paint. He swirled together wilder and wilder mixtures, eventually mixing dried blood, potash (potassium carbonate), and green vitriol (iron sulfate), then stewing them over an open flame. He expected the flask to yield a bloody crimson, but instead a different brilliance appeared—the deep violet-blue glow of a fading twilight. Diesbach called the vivid pigment Berlin blue; English chemists would later rename it Prussian blue.
    Almost eighty years later a Swedish chemist mixed Prussian blue with an acid solution, heated the witchy, foaming result, and produced a colorless gas, undetectable but for a faint smell of bitter almonds. The gas easily condensed into a clear liquid that, even diluted with water, was an exceptionally potent acid. That corrosive liquid became popularly known as Prussic acid, although scientists preferred to call it hydrocyanic acid (from the Greek words hydro for water and kyanos for blue).
    The gas was hydrogen cyanide (HCN), a deceptively simple, spectacularly lethal bundle of hydrogen, carbon, and nitrogen atoms. It could be chemically treated to produce powdery white poisonous salts, usually potassium cyanide (KCN) or sodium cyanide (NaCN). As a group, the three cyanides quickly showed themselves valuable in industrial products. Hydrogen cyanide was used in pesticides, explosives, engraving, and tempering steel, as a disinfecting agent, in creating colorful dyes, and even in making nylon. Sodium cyanide became a favored tool of the mining industry, used to etch away useless rock and extract the gold contained inside. Potassium cyanide was also used in mining, as well as in photography, electroplating, and metal polishing.
    Alexander Gettler, tracking cyanide problems in New York, kept a list of accidental poisonings, such