A is for Arsenic
Fans of Agatha Christie will be familiar with her fondness for poison as a method of dispatching her fictional victims, but they may be less aware of just how accurate and precise her depictions of death by poison usually were. This accuracy stemmed from Christie’s early training as an apothecary’s assistant, or “dispenser”, during World War I – a job for which she clearly felt an affinity.
Kathryn Harkup, a chemist, author and devoted Christie fan, has used the author’s fondness for poison as the basis of her new book, A is for Arsenic: The Poisons of Agatha Christie. Part popular science, part history and part Agatha Christie homage, this rather odd mix turns out to be an engaging one, thanks largely to Harkup’s remarkably lucid and enjoyable writing style. The book is divided into 14 chapters, each dedicated to a particular poison written about by Christie, beginning with arsenic and concluding with veronal.
The discussion of Christie’s depiction of poisons is interesting, but it’s the poisons themselves that are the real stars of the show. Most of us are unlikely to dwell on the intricacies of exactly how poisons affect the body on a physiological and cellular level, nor to have considered just how fine the lines between innocuous substance, miracle cure and deadly poison can be, but in Harkup’s hands the complex workings of poisons becomes a subject of fascination. The denser scientific explanations are broken up with entertaining case studies from the history of toxicology, with particular emphasis on the efforts of scientists and coroners to find reliable methods of detecting and identifying poisons post-mortem (one gruesome method involved tasting the stomach contents of the corpse). Harkup contends that Christie was influenced by many of these cases, and at least one murderer appears to have been inspired in turn by Christie’s writing: in 1977 Roland Roussel poisoned a man with atropine (the principal poison in belladonna) and when police searched his belongings they found a copy of Christie’s The Thirteen Problems, with passages on atropine carefully underlined.
Harkup has such a thorough grasp of her material and communicates the complex chemistry at work with such clarity and wit that even those who don’t consider themselves diehard fans of either Agatha Christie or toxicology are likely to come away with a vastly increased interest in and understanding of both. DV
Bloomsbury Sigma, 288pp, $29.99
This article was first published in the print edition of The Saturday Paper on Nov 7, 2015 as "Kathryn Harkup, A is for Arsenic". Subscribe here.