A Is for Arsenic; The Poisons of Agatha Christie by Kathryn Harkup. Bloomsbury, 2015.

Agatha Christie is perhaps the best known detective novelist of the last century, and her best-known fictional detectives are Hercule Poirot and Miss Marple. This is an analysis of the poisons used in her novels and short stories. (These days murderers – even in England – mostly use guns). Christie has provided an elaborate Appendix of her fictional murders and what the murderer used, poisons and otherwise.  She claims that her stories are based on the true crimes of the day. Her first novel was accepted in 1920; she died in 1976; we presume of natural causes.


Kathryn Harkup points out that Christie knew what she was about. She had volunteered as an apothecary’s assistant during the Great War and eventually became licensed. Her copy of Martindale’s Extra Pharmacopoeia is well thumbed. Harkup, a chemist, investigates the poisons used by the murderer in fourteen of Christie’s novels.


The poisons are arranged in alphabetical order, hence beginning with arsenic. Arsenic was widely available in Christie’s time. It was kept around the house because arsenic, like several of the other poisons Christie uses in her “crime career,” was sold as a pesticide and weed killer.


The symptoms for arsenic poisoning were numerous and not unlike those of other poisons – acute stomach pains, vomiting, and diarrhea. Until other antidotes were developed, the common means of treating someone who had been poisoned with arsenic, either on purpose or by an unintended contact with the pesticide, was activated charcoal. Alternatives to charcoal were developed during the Great War because the Lewisite gas used on the Western Front was an arsenic-based poison.


More recently another poisonous gas, sarin, has been considered a military weapon designed to be used much as Lewisite gas was in the Great War. It stops the production of mucus and hence was at one time used in cough medicine. It is colorless, odorless, and can kill within minutes of receiving a lethal dose. It is the B poison in Markup’s book because one form of the poison was called belladonna.


Hydrogen cyanide is perhaps the most common form of cyanide, a notorious poison. It can be obtained from various sources, such as in the stones of apricots, apples, and peaches. And cassava; the residual cyanide in cassava, an important food source, can be fatal. Hydrogen cyanide is notorious because it was used to kill inmates at German death camps in the last years of World War II. A German chemical firm, IG Farben manufactured it under the trade name Zyklon B. Biting into a capsule containing hydrogen cyanide in a powdery form was a common means of committing suicide amongst the National Socialist elite. Hitler swallowed cyanide but then also shot himself in April 1945.


And so on, through the alphabetical listing that Kathryn Markup has provided. But stopping at two more letters of the alphabet: n – nicotine and o – opium (which includes morphine and heroin as popular forms). Nicotine was a New World drug; tobacco was imported into Europe in the sixteenth century by Spanish explorers and early colonists. It is very addictive. It is most commonly smoked but can also be chewed and snorted. (The latter two are considered declassee; spittoons have largely disappeared.)


Recently electronic-cigarettes have been introduced as a means of reducing the health-related problems associated with breathing in tobacco smoke. The judgment is still out on whether it is a step toward a ‘healthier’ means of consuming what is after all a lethal poison. Never having smoked, I, like many of my generation, nevertheless, ingested ‘secondhand smoke’ riding in the back of our family car.


Not a word about marijuana or hemp (M is represented by monkshood. H by hemlock.), nor cannabis.


Opium, obtained from the opium poppy, is a popular street drug, more commonly consumed in the form of heroin or morphine, which are the more concentrated forms. There is some evidence that opium was used by the ancient Sumerians as an analgesic. As laudanum it was widely consumed in the nineteenth century as pain medicine and to relieve diarrhea. Codeine, another mild form of morphine, was used as a cough suppressant.


Markup doesn’t mention this but morphine was widely used to treat pain during the American Civil War. Hence many of the veterans wounded in the War returned home addicted. Opium poppies are only one of many species of poppies. The seeds from other poppy species are used to flavor bakery goods. We celebrate those growing in Flanders Fields as a memorial to World War I.


But back to Agatha Christie and the use of poisons as a common form of homicide. Entertainment for Christie fans; impressive chemistry; a reminder to us of our connections to the plant world – its occasional perils, and ecstasies.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s