Last spring, I went with my younger son to see the James Bond movie Skyfall. He loved it. I obsessed over one of the major plot points. A chemical one, of course. The villain - a twisted former spy played by Javier Bardeem - was seeking revenge for what he perceived as a betrayal by his agency. According to the story line, he'd been captured, left to be tortured, and when he tried to end it with his cyanide capsule, the poison had dissolved his jaw, disfiguring him instead of killing him.
The poison, he said, was hydrogen cyanide. That can't be right, I said to my son. I believe his response was something along the lines of "Mom, knock it off." Only possibly not quite as polite as that. So I let it go but, yeah, while muttering "But I know I'm right" to myself in a slightly sulky way. So when the talented chemistry blogger, See Arr Oh, organized a Chemistry in the Movies blog carnival this week, I decided this was my moment. (It's actually a terrifically fun blog carnival, with some very smart science bloggers deconstructing movies from Evolution to The Absent Minded Professor). Thislink will get you to many of the posts or you can track them on Twitter at #ChemMovieCarnival.
But about Skyfall and the old cyanide pill story. Cyanide is a famously fast-acting poison due to its ability to induce extreme chemical suffocation of cells and to disrupt enzymatic processes. It's probably most lethal in the gaseous form of hydrogen cyanide (HCN), which the Nazis infamously employed in their concentration camp gas chambers. At a high dose, about 3000 ppm in the air, it can kill in one-to-three minutes. When we swallow cyanide, it's usually as one of the two cyanide salts, potassium cyanide (KCN) and sodium cyanide (NaCN). Sodium cyanide is slightly more toxic but either of these will kill in a trace amount - somewhere between 100-300 milligrams - in five minutes or so. If you want watch the real thing in action - not that I'm recommending it - last year an ex-banker, shortly after being convicted of malfeasance, killed himself with potassium cyanide, acquired on-line, in the courtroom. The website LiveLeaks hasposted a video of the incident.
So cyanide is fast and it is, as I've written before, reliably lethal. It was the poison found, earlier this year, in the body of a murdered Chicago lottery winner. There's a history - usually dated back to World War II - of spies carrying suicide pills, just in case they were captured. These were reportedly calledL-pills (L for Lethal). The International Spy Museum, in Washington D.C.,displays eyeglasses that contained a tiny L-pill compartment - the captured spy could supposedly casually chew on the temple (or arm) of the glasses and release the poison. The Encyclopedia of Espionage cites the case of a CIA mole in the Soviet Union, who eluded prison or worse by biting the cyanide loaded tip of a fountain pen.
If I'm following the Skyfall story right, though, the fictional spies of the British spy used the old fashioned cyanide-in-a-glass-capsule-hidden-in-a-tooth scenario. The idea was that the spy could crunch down if needed; if the capsule worked loose and was accidentally swallowed, the glass would contain the poison. My guess is that this would be usually sodium or potassium cyanide, mostly because they are the versions usually found in pill or capsule form.
But, in the movie scenario, it's identified as hydrogen cyanide. And according to the script, it's not lethal but corrosive. So - since my son wouldn't put up with me doing it - let's pick that apart here. Although hydrogen cyanide (HCN) is best known as a lethal gas (it actually has a chemical warfare classification), it can also be found in liquid form, where it is usually referred to as Prussic Acid or hydrocyanic acid. This is what I suspect the Skyfall scriptwriter grabbed onto when he chose it for his destructive suicide pill. It's worth noting that KCN and NaCN are considered mildly corrosive salts and tend to cause distinctive lesions the intestinal walls.
But, of course, they don't have that "acid" nomenclature. The problem is, though, that the word acid doesn't often equal to "melt your bones." Most acids are far less destructive. Think of citric acid in fruits like oranges and limes. Or acetic acid, the primary constituent in vinegar. Hydrocyanic acid is more potent than those but it's also classed as a weak acid. (Or at least I think of it as potent because of the following effects but, as Alex Berezow of RealClearScience reminded me, on the acid-scale it actually ranks below acetic and citric acids). If you look it up, you'll find that mixed with other substances, hydrocyanic is implicated in causing stress-fractures in metal and if it's stabilized with sulfuric acid - a famously strong formulation - the combination can be corrosive to steel. In other words, "improbable" is the best word for the melt-my-face scenario in Skyfall. Or perhaps "impossible."
But, to give my son the last word here, there's also a problem with the obsessive chemistry writer. It turns out she's more than capable of ruining a good movie plot.
Images: Model of the "cyanide-damaged teeth", courtesy of the International Spy Museum and its exhibit: Exquisitely Evil: 50 Years of Bond Villains 2) Poster for Skyfall/Empire Design/Wikipedia
