Poisons of Dame Agatha: Author Kathryn Harkup takes Kolkata on an intriguing tour of toxins

“Good evening, ladies and gentlemen,” said the announcer at the Tollygunge Club lawns on a cool Friday night in Kolkata.

“Welcome to the Apeejay Kolkata Literature Festival.

“We are shortly going to begin our next session titled Bloody Scotland and Dame Agatha, celebrating 125 years of Agatha Christie,” announced the lady, pausing to sip from a glass of sparkling red wine.

“And let me also wish…” she stopped, staggering oddly.

Stuttering, she fell down dramatically on the stage, gasping for breath. The glass rolled onto the lawns.

“She has been poisoned!” a man with a faux Hercule Poirot accent claimed, the absence of that famous moustache decidedly evident.

“You cannot leave the premises unless our probe is finished.”

It was a nice, quirky way to usher in a discussion on Agatha Christie who comfortably remains the best-selling author of all time, outsold only by the Bible and Shakespeare.

Lost in the labyrinth of her twisted plots, however, what we who grew up savouring her crime fiction may not have noticed is the absolutely ingenuous way the Queen of Crime used deadly chemical substances to kill off her characters.

In the 66 detective novels that Dame Agatha penned in her prolific career, she poisoned more than 300 characters with 30 killer compounds that she used in a staggering array of creative methods.

And she wrote with such a high degree of accuracy that there have been documented cases of doctors consulting her novels to understand the symptoms. Her work has been read by pathologists as reference material in cases of real poisoning.

“Agatha Christie used poison to kill her characters more often than any other crime fiction writer.

The poison was a central part of the novel, and her choice of deadly substances was far from random; the chemical and physiological characteristics of each poison provide vital clues to the discovery of the murderer,” argued chemist and science communicator Kathryn Harkup during the launch of her book A is for Arsenic: The Poisons of Agatha Christie.

Harkup dwells on 14 poisons, in alphabetical order, in 14 of Christie’s novels. In her own words “whittling down the variety of poison wasn’t easy”, but she discusses each novel in a different chapter and goes on look at why certain chemicals kill, how they interact with the body, and the feasibility of obtaining, administering, and detecting these poisons both during Christie’s time and today.

“There wasn’t an easy way to select only 14,” Harpur said, “but I have tried to use only those poisons each of which has a medical case or a real-life tale behind it.

“And I also wanted to show how the poisons themselves served as clues, if you knew where to look”.

The British author, who was born in 1890, certainly lived and worked in a time when laying hands on deadly chemical compounds were easy but what lies behind the well-researched choice of her poisons?

What explains Christie’s precision about symptoms of overdoses, the availability, detection of compounds and the efficacy of antidotes?

And finally, how did she manage to get such verifiable information that keeps on impressing physicians even in the new millennium?

Harkup says the answer may lie in Christie’s background, in her early life as an apothecary’s assistant during the first and second world wars, giving her direct experience of handling poisons and a lifelong interest in toxicology.

Christie volunteered as nurse in a hospital in Torquay, the place of her birth, studied for the professional examinations and qualified as a dispenser in 1917.

Dame Agatha never looked upon herself as anything but an entertainer and she is perhaps more popular than critically acclaimed. And that is what irks Harkup, who says “we don’t tend to appreciate the way she brought science to the people.”

“She was a bloody good novelist with an ability to create fiendish plots but also a brilliant science communicator. She uses complex substances in accurate detail but never alienates the common reader who has no detailed medical expertise.”

In fact a degree holder or a medical student won’t have a special advantage over the common reader, except perhaps appreciating more the way in which she uses the poison to develop the plot.

“We underestimate the depth of her scientific knowledge and creative brilliance. In this book I sought to do justice to it.”

Christie made science seem cool, as it were, and inadvertently ended up playing a role far more crucial that she would have herself bargained for.

“In India, you have a fantastic atmosphere. Science is very popular among students unlike in the UK where we struggle to recruit them.

“Christie’s novels carry a message that science is a universal language like any other. It’s just another way of looking at the world,” said Harkup who admitted that her background as a chemist gave her new insights and made re-reading of Christie “an absolutely rewarding experience”.

The Queen of Crime, she said, was 50 years ahead of her time in using many compounds that were not, and never have been, used as medicine.

“In the House of Lurking Death, for instance, Christie uses ricin as a poison. The first real-life murder that involved ricin happened 50 years later.”

Harkup’s favourite Christie novels include Five Little Pigs and Then There Were None, where it can be argued that chemistry developed the plot more than the characters. The time, for instance, it takes for hemlock to take effect (15 minutes) is sufficient to allow five potential murderers to execute their plan.

In some cases the poison’s strengths or idiosyncracies allow the detectives to solve the mysteries.

It is an intriguing thought and Anuja Chauhan, the bestselling Indian author of The Zoya Factor, Battle For Bittora or Those Pricey Thakur Girls, who was also part of the panel, agreed. Dom Hastings, the director of Bloody Scotland — the annual festival of Scottish crime fiction — was also among the panelists in the session moderated by Sumit Ray.

Chauhan, who had a successful career as an adscript writer, acknowledged how entire structure of a Christie ‘whodunnit’ was created around a poison.

“If you like to talk about poisons,” said Harkup, " you have to talk about Agatha Christie. More than Queen of Crime, she was the Queen of Poison.”