“The name ‘arsenic’ has become almost synonymous with poison – it could be argued that it represents the gold-standard of criminal poisoning.”

Do you ever find yourself reading a book or watching a film and there’s a character in it with an unusual job and you go, “I could do that”? It happens to me with alarming regularity, but it really kicked into effect with this book. I found myself wishing I could redo everything and have studied science for longer at school and gone on to be a toxicologist. Of course, I’m sure this desire will last only as long as it takes for this book to fade a little from my memory, but suffice to say at this moment, there’s a part of me that wants to dive back into education and switch from artistic pursuits to scientific ones.

My Agatha Christie obsession remained forefront as I delved into A is for Arsenic, which takes a look at a bunch of poisons and both describes how they work and how Christie used them in her stories. Not everyone knows that Christie worked as a pharmacy dispenser during both wars, and it was here that she picked up all of her detailed knowledge on the world of poisons. The most common cause of death among her characters was poison, and she always did her best to ensure the science was correct. As Kathryn Harkup recounts here, it seems that most of the time she was spot on.

The fourteen poisons covered in the book are arsenic, belladonna, cyanide, digitalis, eserine, hemlock, monkshood, nicotine, opium, phosphorus, ricin, strychnine, thallium and Veronal. They form a blend of very well known killers, and some that are downright obscure. For example, ricin and thallium were both unheard of as methods of murder before Christie wrote about them. However, it seems that sometimes her stories gave rise to ideas in the real world, and there’s been more than one killer caught because he had one of her books stashed away in his study. Conversely, on a few occasions people have been saved by recognising the symptoms of poisoning from reading a Christie novel. While there are some people who consider her detailed use of science to be damaging, her books are generally highly praised for their accuracy.

Each chapter studies a particular poison, giving details of where it can be obtained, how it was discovered, how exactly it kills, and whether there is an antidote. Among these, we also learn about real life cases involving the poison, and it all gets related back to one of Christie’s plots and how accurate she was. There are some surprising facts here, not only about the poisons, but about Christie herself, and we learn a little more about her scientific mind. The poisons are the real stars though, and it’s fascinating to learn about the very close relationship between morphine and heroin, quite how poisonous pure nicotine is, how best to mask the bitter taste of cyanide, and which poisons are still used today. Hemlock, for example, while being quite famous for its toxic qualities, hasn’t been recorded as being used to intentionally kill someone since the days of Socrates. Christie made use of it in Five Little Pigs, one of my favourites.

Although for the most part Harkup avoids sharing spoilers, there are a few present, but always headed with a warning to skip ahead if you don’t want to see “whodunnit”. Generally we aren’t told, but sometimes the solutions need to be explained to give an extra detail on how the poison is used within the story. For anyone with an interest in Christie’s work or toxicology (or ideally, like myself, both), this is a startlingly good read. If not inspiring me quite fully to become a toxicologist, I am at least inspired to return to the murder mystery I started writing. I believe there is some cyanide in a cocktail I need to sort out…