Slobodan
Praljak, formerly a general in the Croatian Army and Croatian Defense Council,
was convicted of crimes against humanity and violations of war/Geneva
Convention during the Croat-Bosniak War (1992-1995). He received a 20-year
prison sentence in 2013. At an appeals hearing in The Hague on November 29,
2017, and upon hearing that his conviction would be upheld, Praljak spoke,
“Judges, Slobodan Praljak is not a war criminal. With disdain, I reject your
verdict!” He then drank from a small bottle and said, “What I am drinking now
is poison.” The judge stopped the hearing and medical professionals were
summoned. He died a short while later.
Image of
Slobodan Praljak in the act of drinking a vial of liquid during his appeals
hearing at The Hague on November 29, 2017.
It has now been
reported by Dutch officials that Slobodan Praljak committed suicide by drinking
cyanide.
What is cyanide?
Cyanide, also
known as hydrocyanic acid, has a molecular formula HCN and its molecular weight
is 27.03 g/mol. HCN’s boiling point is 25.6°C (78.1°F). Hydrogen cyanide was
first isolated from the pigment Prussian blue; hence another alternative name is
prussic acid. In the 1800s, cyanide was given its modern name from the English
word cyan, which means a shade of blue. Hydrogen cyanide and its potassium and sodium
salts have been used as fumigants, insecticides, metal polishes, and in
gold/silver electroplating solutions. Cyanide vapor can be detected by a
characteristic almond odor, but it is estimated that up to approximately 50% of
the human population cannot detect this odor due to a recessive genetic trait.
Cyanide can be found in trace levels in the human body as a result of normal
metabolic processes, as well as from eating a diet high in cyanogenic
foodstuffs (e.g. apples, apricots, bitter almonds, and cherries) and smoking
cigarettes.
Chemical structure of Hydrogen Cyanide
Structure drawn by Kevin G. Shanks (2017)
What does cyanide do to the body?
Cyanide inhibits
cellular respiration by binding to the iron atom in the cytochrome c oxidase
enzyme, an enzyme involved in the last step of the mitochondrial electron
transport chain. Normally, during this step, molecular oxygen is converted into
water. This inhibition causes oxidative phosphorylation to halt and the Kreb’s
cycle is disrupted. Adenosine triphosphate (ATP) cannot be produced by the
mitochondria. Pyruvic acid, formed during glycolysis, accumulates and is
modified anaerobically to lactic acid. Lactic acid buildup causes metabolic acidosis.
Oxygen also builds up in tissue and alters the gradient for oxygen release from
hemoglobin, which produces cellular hypoxia.
The onset of
symptoms of cyanide poisoning is dependent on the route of
exposure/administration. Hydrogen cyanide vapor is rapidly absorbed through
inhalation. Potassium and sodium cyanide salts are more easily absorbed via
oral ingestion, but are absorbed at lower rates and if ingested orally, they
are converted to hydrogen cyanide via gastric acids. The lethal dose of hydrogen
cyanide has been estimated to be 100 mg while sodium/potassium cyanide’s lethal
dose has been estimated to be 200-300 mg.
Acute
intoxication symptoms of cyanide poisoning are central nervous system
stimulation, headache, dizziness, tachycardia, shortness of breath, rapid
breathing, and vomiting. Other symptoms that may occur after initial
intoxication include seizure, bradycardia, hypotension, coma, and cardiac arrest.
Chronic administration of cyanide can lead to abnormalities of vitamin B12,
folate, and thyroid function as well as severe longer-term neurological issues.
What does the body do to cyanide?
Cyanide is biotransformed
to thiocyanate by the hepatic enzymes rhodanese and
beta-mercaptopyruvate-cyanide sulfurtransferase. Thiocyanate is then excreted
into the urine. Other metabolic pathways include trapping of cyanide by
hydroxocobalamin via formation of vitamin B12, oxidation to formic acid and
carbon dioxide, and pulmonary excretion of unchanged substance. The elimination
half-life of cyanide in whole blood is reported as 0.7-2.1 hours. Volume of
distribution is 0.4 L/kg.
Has it been used as a historical poison?
Because of its
ease of use and toxicity, cyanide has appeared throughout history regularly as
a poison, in warfare, suicides, and homicides. Some of the most well-known modern
cases are:
It is rumored
that cyanide played a role in Grigori Rasputin’s assassination in 1916. He was
allegedly given cyanide-laced cakes and Madeira wine.
Hydrogen
cyanide, as the pesticide Zyklon B, was used in gas chambers to murder people
in the Nazi concentration camps during World War II.
In the 1940s,
Erwin Rommel, Eva Braun, and Heinrich Himmler all committed suicide by cyanide
liquid ingestion. The six children of Joseph Goebbels were murdered by being
injected with morphine by Helmut Kunz, an SS dentist, and administered cyanide Ludwig
Stumpfegger, Adolf Hitler’s personal doctor.
In 1974, Ronald
Clark O’Bryan gave potassium cyanide laced Pixie Stix to his son, daughter, and
three other children. The son ate the candy, while none of the other children
did. The boy died. During the police investigation it was determined that the
boy had a life insurance policy on him worth a very large amount of money. The
father was convicted of murder in 1975 and was executed via lethal injection in
1984.
In 1978, in
Jonestown, Guyana, 907 people died in a mass suicide event lead by Jim Jones.
Cyanide, alongside diazepam, chloral hydrate, and promethazine, was consumed
via a grape flavored beverage.
In 1982, seven
people died from a series of drug tampering cases in Chicago, Illinois. Tylenol
brand acetaminophen had been laced with potassium cyanide by an unknown person.
Several more deaths occurred in copycat crimes. No one was ever convicted of
these homicides.
In 1988, Stella
Nickel was convicted of murdering her husband and another woman with
cyanide-laced Excedrin tablets. She received a 90 year prison sentence.
Cyanide has also
been used in capital punishment in the United States, with the last gas chamber
execution via cyanide occurring in Arizona in 1999. It still remains an option
for capital punishment in six states.
In 2012, Wall
Street trader Michael Marin consumed a cyanide tablet while in the courtroom shortly
after a guilty verdict for arson was rendered.
In 2015, John
McLemore committed suicide using potassium cyanide. He was currently recording
a narrative for the investigative journalism podcast S-Town.
Conclusion
Cyanide is a
rapidly acting substance that causes death via disruption of cellular
respiration and results in hypoxia and cardiac arrest. It is found as hydrogen
cyanide or as potassium or sodium salts. It has been effectively used
throughout history as an agent to murder people and has been implicated in
suicides
References
Baselt, R. Cyanide.
Disposition of Toxic Drugs and Chemicals in Man. Eleventh Edition. Biomedical
Publications: Seal Beach, CA, 536-539 (2017).
Principles of Forensic Toxicology. Fourth Edition. Barry
Levine. AACC, Inc. (2017).
