An Introduction to Arsenic

This chapter provides an introduction to the element arsenic and to its position in the consciousness of the general public as number one in the poison index. Its association with poison has even led to the satirical suggestion that it should be removed from the chemistry periodic table — this despite the fact that it is one of the natural elements that make up the Earth. Many people are uncomfortable with chemicals, and within this general chemophobia, arsenophobia has a particularly powerful position. The association has been used to great effect in plays such as Arsenic and Old Lace, but has also been used to add emotional wallop to sell everything from lingerie to paint to music. This chapter reinforces how arsenic is uniquely embedded in our social fabric, probably to a greater degree than any other element.

Some Background

This book is an updated and more focused follow-up to Is Arsenic an Aphrodisiac? The Sociochemistry of an Element, by co-author W. R. Cullen, published by the Royal Society of Chemistry in 2008. The 2008 book covered a wide range of topics, some of which will not be revisited here because we feel that enough has been said about, for example, arsenic's role in crime (a substantial role), chemical warfare (also substantial), sudden infant death syndrome (not involved), and the death of Napoleon (a myth). Some mention will be made of other topics previously covered when necessary, to place them in context and add new information, but otherwise the material and the approach in this volume are different with more of a focus on sociochemistry, which we define as what takes place at the interface between society and chemistry. We are convinced that arsenic has the broadest, deepest and most fascinating sociochemistry of all of the elements. As the interface between society and arsenic is demonstrated largely by the effects of arsenic on life, human and other, this work explores primarily how we are all exposed to arsenic in one form or another and examines whether this exposure is a cause for concern.

To begin, the word "arsenic" appeared in the English language in 1389. Arsenic is one of the 98 natural elements (Box 1.1) that make up our universe and ranks somewhere between 46th and 54th in the composition of the earth's crust, between 24th and 28th in seawater, and about 31st in the human body. However, it is firmly fixed at number one in the mental poison index of most of the world's inhabitants, even though quite a few other elements and their compounds are much more toxic (think, for example, of non-toxic carbon as diamond and carbon dioxide and toxic carbon as strychnine and sodium cyanide).

"Toxic arsenic" has become embedded in our social fabric, for good and for ill, as is exemplified in a very old (and corny) joke:

A woman walks into a drugstore and asks the pharmacist for some arsenic.

"Ma'am, what do you want to do with arsenic?" asks the pharmacist.

"Kill my husband," answers the woman.

"I can't sell you arsenic to kill a person."

The lady lays down a photograph of a man and a woman in a very compromising position. The man in the picture is her husband and the woman is the pharmacist's wife. He takes the photograph in his hand and nods.

"I didn't realize you had a prescription."

Arsenic has become so synonymous with poison that Pulitzer Prize-winning author Deborah Blum is sure of the answer when she asks in a blogpost, Is arsenic the worst chemical in the world? In a satirical piece, some parents of school children in Colorado, United States, suggested that arsenic should be removed from the ubiquitous charts known to chemistry students as the periodic table of the elements. Such negative reactions are part of a widespread aversion to, and even fear of, chemistry and chemicals, regardless of the actual danger that they pose. This fear even has a name: chemophobia.

Chemophobia is well acknowledged by society as a whole. According to science writer Valerie Brown, "individuals mentally assess risk in a similar way, but risk perception is shaped by several largely unconscious emotional processes shared by scientists and non-scientists alike. The human brain is hard-wired to react quickly and defensively to perceived threats of any kind. This includes physical threats, sights, sounds, smells, and even words or memories associated with fear or danger. For example, the word 'chemicals' has been shown to trigger an unconscious fear reaction in members of the general public, leading to chemophobia." Arsenophobia is this emotion focused on this particular element.

This general association of arsenic with poison began to emerge at the time of the industrial revolution of the 1700s, when arsenic trioxide for use as a rat poison became easily accessible, as described in Chapter 2 of Cullen's 2008 book. All details of the numerous criminal poisoning trials involving the use of arsenic were reported in the popular broadsheets, whose authors pandered to the basest interests of the general public.

When the World Health Organization (WHO) moved ultraviolet light tanning beds to its highest cancer risk category in 2010, the message was publicised by comparing the danger with that of arsenic: "Tanning beds as deadly as arsenic." That same year, political pundit John Feehery wrote that US President Obama had said about the stimulus package that it was "the best thing since sliced bread [but that the] Republicans say it was the worst thing since the invention of arsenic." And, still in the United States, Republican Karl Rove accused the Democrats of adding "arsenic to the nation's political wells."

Then there is the term "the arsenic hour," which first appeared in 1975 and which refers to the time of day when both children and parents have come home tired and hungry (though what the use of arsenic might be in the parents' minds during this hour is open to conjecture):

Between the nap and the twilight
When blood sugar is starting to lower,
Comes a pause in the day's occupations,
That is known as the Arsenic Hour.

But arsenophobia is not restricted to the general public — even scientists have the disease. The arsenic entry in the Periodic (Table of) Videos, produced by a well-known team based at the University of Nottingham, UK, provides an extreme example. The phrase "toxic" is used numerous times, incorrectly, in the video in relation to a vial of elemental arsenic.

Elemental arsenic is in fact not toxic to humans, but a few arsenic compounds are very toxic and have been used for criminal purposes from the time of the ancient Romans to the present day. This negative view of the element has been reinforced in the crime fiction of authors such as Dorothy Sayers and Agatha Christie. Arsenic also plays a major role in more serious fiction, such as in the classic American short story "A Rose for Emily" by Nobel Prize-winning...