MAD MONKS, KGB AGENTS, AND SLEEPING DOGS

Grigory Rasputin, the "mad monk," was a very powerful man in the court of Tsar Nicholas of Russia. This illiterate Siberian peasant with stringy hair, tangled beard, and a strong body odor established a position for himself in the Romanov court when he apparently saved the life of Nicholas's son Alexis, who was wasting away after sustaining a minor blow to the thigh.

Alexis was a hemophiliac, thanks to a gene he had inherited from his mother, Alexandra, the grand-daughter of Queen Victoria. Rasputin told the tsarina that the way to save the boy was to keep him out of the clutches of the doctors and to pray. The advice turned out to be sound, because as soon as the doctors ceased their prodding and probing, Alexis's internal bleeding stopped. The tsarina and the tsar became indebted to Rasputin.

Rasputin's growing influence and bizarre behavior aroused a great deal of jealousy and concern among those at court. They frowned upon the monk's belief that to be absolved of sin, one must first commit a sin; the greater the sin, the greater the forgiveness when the sin was renounced. Indeed, if a young female penitent had not sinned enough, Rasputin was more than willing to help her.

The final straw for Rasputin's enemies was when the tsar began to take his advice on political matters. Under the leadership of Prince Ytissopov, these courtiers hatched a scheme to eliminate the demonic clergyman who had already developed a supernatural aura after miraculously recovering from a stabbing. The conspirators would take no chances: they would poison him with cyanide. Yussopov enticed Rasputin to a party where he was served chocolate cake laced with potassium cyanide. The cleric ate and ate, but, to the horror of the onlookers, nothing happened. Was this fiend really possessed of supernatural powers? The conspirators panicked and one of them shot Rasputin in the chest, point blank. When Yussopov bent over to see if Rasputin had finally been dispatched, the corpse got up and began to chase him. Two more shots rang out and the monk finally slumped to the ground. He was then dragged outside and thrown into the Neva River, where, according to the autopsy, he finally drowned.

Why had the cyanide not done its job? After all, it is a notorious killer. Cyanide deactivates one of the most important enzymes in the body, cytochrome oxidase. This enzyme catalyzes the prime energy producing reaction in cells - the one between glucose and oxygen - and when it is rendered inactive the body is left with no energy to run vital organs like the heart and lungs. Death rapidly ensues.

One possible explanation for the botched poisoning is that the schemers used old potassium cyanide that had become inactive, reacting over time with carbon dioxide from the air. Under these conditions, potassium cyanide slowly converts to potassium carbonate and releases hydrogen cyanide gas into the air. This theory is not as improbable as it may sound. Just a couple of years before the Rasputin incident, a Russian circus elephant had gone berserk and had had to be destroyed. The animal was very fond of cream cakes, and those charged with killing it decided to fill a hundred of these pastries with potassium cyanide. Although the elephant ate all of the cakes, it was unaffected - the unfortunate pachyderm eventually had to face a firing squad.

Usually, cyanide is a very "dependable" poison. That is why, during the Cold War, Soviet KGB agents relied on it to kill their political enemies. This came to light in 1957 when an exiled Ukrainian political leader and publisher of a Munich-based anti-Soviet newspaper was done in with cyanide. Some clever chemistry was involved. The KGB agent who was assigned the task of executing the publisher was equipped with a device that would generate hydrogen cyanide gas by mixing potassium cyanide with sulfuric acid. The gas could be directed at the intended victim's face, causing a rapid death that would be ascribed to a heart attack. (Incidentally, this is the same chemical reaction that was employed in the Nazi gas chambers, and it is still used in some American states where executions are carried out.)

Why was the KGB agent himself not affected by the gas as he carried out the assassination? He could have worn a gas mask, but this would not have been conducive to sneaking up on someone in public. There had to be another way. Soviet chemists had worked out an ingenious antidote system based on the body's mechanism for ridding itself of small doses of cyanide.

They knew that an enzyme called rhodanase converts cyanide to thiocyanate, which is excreted in the urine. This reaction, however, requires the presence of the thiosulfate ion, which is normally present in the body in very limited amounts.

The morning of the assassination, the agent consumed some sodium thiosulfate (also known as "photographers' hypo") for breakfast in order to prepare his body to handle the cyanide. Just before the fateful encounter, he crushed an ampoule of amyl nitrite in his mouth and inhaled deeply. This led to the synthesis of an altered form of hemoglobin called methemoglobin in his blood. Methemoglobin has a very high affinity for cyanide and binds the poison until it can be eliminated through conversion to thiocyanate as described earlier.

Although the chemistry is sound, this defense against the cyanide is not very reliable: the dose of the antidotes would have to be just right, since excess amyl nitrite is itself toxic. But it is interesting to note that the modern treatment for cyanide poisoning involves amyl nitrite inhalation followed by the intravenous administration of sodium nitrite (which also generates methemoglobin) and sodium thiosulfate.

This is exactly the treatment that was used several years ago on a Mexican medical student who, unable to wake up his sleeping dog, attempted mouth-to-snout resuscitation. It was all in vain - not only did the dog die, but also the student passed out. The attending physician at the hospital the student was taken to noted the odor of bitter almonds on the patient's breath and suspected cyanide poisoning. The dog had not been asleep; the animal had accidentally swallowed cyanide and had eliminated some of the poison through its lungs. Obviously, when it comes to cyanide-eating canines, it is best to let sleeping dogs lie.