Review: A is for Arsenic: The Poisons of Agatha Christie by Kathryn Harkup

A is for Arsenic: The Poisons of Agatha Christie [2015] – ★★★★★

15 September 2020 marks 130 years since the birth of Agatha Christie in 1890, and this review is meant to pay tribute to the ultimate Queen of Crime. The author of A is for Arsenic is Kathryn Harkup, a chemist by profession, who decided to plunge into all the poisons that Christie used in her books to come up with her perfect crimes. In A is for Arsenic, we first read about the scientific properties of each of the poisons used by Christie in her fiction, from arsenic and belladonna to opium and phosphorus (including their histories and the ways they kill), before the author illuminates the real cases involving these poisons, and finally talks about the fictitious cases in Agatha Christie’s books. It is clear that reading about different poisons has never been as morbidly fun or interesting as with this book since Harkup is an intelligent and succinct writer with a great sense of humour. A is for Arsenic is sure to fascinate and delight this Halloween season.

Agatha Christie was always a very considerate writer who liked to research her books thoroughly before penning them. Once trained as a nurse, Christie knew something about poisons and their applications, and the knowledge she lacked she liked to gather. Harkup says that Christie’s “murders” and their solutions were almost always scientifically-plausible and that element alone made her books stand above one’s average detective thriller. Christie also liked to experiment, and some of her crimes in books are committed by rather unusual means where often the poison is either left untraceable or can be taken for an accidental overdose of a common prescribed medication.

Kathryn Harkup structures her book in the following order: (i) a brief synopsis of a book by Agatha Christie where a poison was used; (ii) a history of a particular poison; (iii) the scientific characteristic of a poison, including the nature of its compound and how exactly it kills its victim; (iv) some real-life examples or famous real cases where that poison was administered to kill; and, finally (v) Agatha Christie’s fiction and how a particular poison was used by a murderer in the story. Each poison is listed in an alphabetic order, and we read about such dangerous compounds and plants as arsenic, belladonna, cyanide and hemlock. Their histories are often as illustrious as their reputation. For example, eserine is derived from beans grown in West Africa and were often used by local people to conduct trials by ordeal (to prove either guilt or innocence of an individual who swallows the beans). Similarly, we read how the poisonous hemlock may be mistaken for cow parsley, and how Socrates might have died by swallowing a concoction made of hemlock.

Since the author is a PhD in chemistry, we read detailed and well-explained passages on the nature of chemicals in poisonous compounds and how they interact with other substances. What exactly produces a poisonous reaction; is there an antidote?; and what is the history behind scientific discoveries of each compound so far? In this vein, we read how the compound ricin is produced by the castor oil plant ricinus communis, which grows in the world’s tropical regions, and find out how the use of white phosphorus in match-making factories in the 1880s was responsible for one horrific disease – the phosphorus necrosis of the jaw or “phossy jaw”. There has always been a fine line between the medicine that gets us better and the compound that kills – a harmless stimulant may turn into a poisonous killer in an instant and with just a few more milligrams of the same compound. Thus, it is the doctors who have often straddled that fine line, and that may explain their high number as characters in Christie’s literary creations.

Both the scope and depth of Harkup’s book is impressive, but, more impressive still is the research, especially her research into some very little-known real cases of poisoning by some very rare substances. The amazing thing is that the real cases presented in the book seem even more bewildering and unbelievable than any fiction that Christie penned. To that effect, we read about the exploits of the infamous George Henry Lamson, a doctor who poisoned his victim using aconitine (devil’s helmet or monkshood) in a cake, and even about one rare case of poisoning by nicotine! from the year 1850. When Harkup finally returns to Christie’s stories, she speculates on how the murderer there could have obtained the poison and whether it all is sufficiently realistic given all the science. The great thing here is that the author never gives out any spoilers – she says just enough to whet our appetites so that we will rush to pick up this or that detective story.

The conclusion is that A is for Arsenic is a “must-read” for any fan of Agatha Christie, as well as for all those who either like to marvel at all things macabre in science or crime, or who are simply interested in various poisons and their effect on the human body.