A is for Arsenic (4 page)

There has been a lot of speculation about the death of Napoleon Bonaparte in 1821. During the last months of his exile on St Helena he was very unwell, and was attended by many doctors, both French and British. The emperor was suffering from severe stomach pains, and medical treatment
seemed to have little effect on him. When he died, seven doctors attended the autopsy and concluded that Napoleon had died of stomach cancer, but rumours of poisoning were swift to circulate. As you might expect, the French accused the British and the British accused the French. Very little could be done to confirm or deny poisoning at the time as reliable tests were not available.

In the 1960s samples of Napoleon's hair, cut from his head shortly after death as mementoes, were analysed for arsenic content. Unusually high levels of arsenic were discovered, opening up questions as to how it might have got there. One theory was that it came from his wallpaper; when a sample of the wallpaper from his bedroom was discovered in the 1980s, analysis showed significant levels of arsenic, 0.12g/m
2
.
¹⁵
In 1893 a detailed study showed that wallpapers containing between 0.6 and 0.015g/m
2
arsenic could cause health problems, and even values as low as 0.006g/m
2
were potentially hazardous.
¹⁶
St Helena had a warm, damp climate likely to encourage the growth of mould in wallpapers, but even so this is unlikely to have generated enough trimethylarsine to kill Napoleon. The wallpaper certainly may have contributed to his poor health, though, and he did what anyone else would do when they feel ill, he called in a doctor. Unfortunately the doctors who attended Napoleon did little to help, and they introduced more toxic compounds into his body in the form of medicines, though probably not actually with the intention of poisoning him.

The range of medicines available to a nineteenth-century physician was limited, and those available were generally used because they had been shown to produce an effect on the human body, such as purging (vomiting and diarrhoea) or sweating. Any recovery from an illness was usually incidental, and clinical trials or follow-up consultations were practically unheard of. Sick people often got better in spite of their
doctor's ministrations, rather than because of them. The compounds that produce the most dramatic effects on the human body are often highly toxic, and before the twentieth century a doctor's medical bag would almost certainly contain compounds that are considered highly dangerous today.

One medication in common use in the nineteenth century was Fowler's solution, a tonic prescribed for the treatment of a variety of illnesses. Fowler's solution was introduced into the
British Pharmacopoeia
in 1809, initially as a treatment for malaria. It had no taste, which made it preferable to the bitter quinine medicine usually prescribed. The number of prescriptions for Fowler's solution increased, along with the number of complaints it was prescribed for, from skin conditions to asthma. The key ingredient in Fowler's solution was, of course, arsenic, in the form of potassium arsenite (K
3
AsO
3
).
¹⁷

Finding arsenic in a Victorian corpse would, therefore, not be that surprising. The prosecution in a criminal poisoning case had to prove not only that arsenic was the cause of death, rather than incidental, but also how the arsenic had been obtained and administered to the victim.

The Arsenic Act was passed in 1851 in an attempt to regulate and control the sale of arsenic.
¹⁸
The act made it a legal requirement for sales to be recorded in a register along with the name of the purchaser, the quantity bought and the purpose it was to be used for. The Act also required any arsenic not used for medical or agricultural purposes to be ‘coloured' with either soot or indigo dye, to reduce the risk of mistakes such as the sweet incident. Unfortunately, there were large loopholes in the Act; for example, there were no restrictions on who
could sell arsenic compounds, and anyone determined to murder another human being was unlikely to have any qualms about recording false information in the poison register. Over time the rules on the sale of arsenic, and other poisons, were tightened up. The sale of poisons was restricted to a few professions and shops, such as pharmacies, and anyone buying a poison had to be known to the pharmacist, or vouched for by someone who knew both the pharmacist and the purchaser. Even if criminal poisonings were carried out there should in theory have been a system for tracking the poisoner through the poison registers. It was still frighteningly easy to get hold of arsenic, though, and a huge number of ‘legitimate' uses could be recorded in the poison register, but it was up to the prosecution to prove that the accused's intentions had been otherwise.

A case could be complicated further if the accused used the ‘Styrian defence'. This was a legal argument used to explain the presence of high levels of arsenic in a corpse. In 1851, a report appeared in a Viennese medical journal about men from the Austrian region of Styria who regularly ate arsenic. They would crunch lumps of arsenic trioxide between their teeth, or grate it onto their toast two or three times a week. They would start with a lump the size of a grain of rice, and gradually increase the dose until they could eat quantities normally considered lethal with apparent impunity. The reason for this strange choice of dietary supplement was because they said it gave them ‘wind', by which they meant that they could breathe more easily while doing hard physical labour in the thin mountain air. The arsenic also gave the men more physical bulk and clearer skin, making them more attractive. Women in the region used arsenic too, as it gave them a more curvaceous figure and a ‘peaches and cream' complexion.

The arsenic was indeed killing off any bacteria that might have caused spots and blemishes, but it was also triggering oedema – retention of fluid in the muscles – and vasodilation of the capillaries under the skin to give the rosy-red cheeks. The habit might be expected to have made the arsenic-eaters
feel ill, but some complained they actually felt unwell when they missed a dose. On first appearances it might look as if they were developing a tolerance of arsenic – which would have been handy for anyone who suspected a relative of trying to bump them off. However, these individuals were not developing a true tolerance. Eating large quantities of arsenic was possible because it was swallowed in relatively large lumps, rather than as a fine powder or dissolved in a liquid. Much of the arsenic would have been excreted before it could be absorbed into the bloodstream.

After reading about the Styrian arsenic-eaters, their attractive appearance and apparently excellent health, some people across Europe and America also started taking arsenic. Arsenic would be used as a beauty treatment, applied directly to the skin, or dissolved in water and drunk in small quantities to improve general health. Agatha Christie had read about arsenic-eaters, and described a widow in
Evil Under the Sun
who had the advantage, or disadvantage, of having an arsenic-eater for a husband, which enabled her to walk free from her trial for his murder.

Arsenic is a cumulative poison, and levels would have gradually increased inside an arsenic-eater's body until dangerous or potentially lethal levels were achieved. Even if their death was not attributed to arsenic poisoning, arsenic-eaters were relatively easy to identify post-mortem as the arsenic acted as a preservative in the body, killing the bacteria that would normally drive the process of decomposition. The burial tradition in Styria involved the removal of a corpse from a grave after twelve years; land for graves was in short supply, so the bones of the deceased were removed to a crypt, and the plot was left vacant for the next occupant. Arsenic-eaters were often found so well preserved, even after twelve years, that they were recognisable to family and friends when they were disinterred. The presence of arsenic in corpses may lie behind some vampire legends, which began in central and eastern Europe.

The preservative properties of arsenic led to its use in the embalming process, until it was realised that this would mask
any arsenic that was present owing to a homicidal poisoning. Arsenic was banned from use in embalming, to be replaced by formaldehyde. Even then, the problem of arsenic contamination of a corpse did not go away. Arsenic is a common mineral in soil, and a dead body could potentially absorb it from the ground it was buried in.

Arsenic bonds very strongly to sulfur atoms, of which there are many in the body, particularly in the hair. This provides a useful record of arsenic exposure over the lifetime of the hair, as arsenic is deposited at the roots within hours of ingestion. As the hair grows, the arsenic is retained at a fixed position. Hair grows at a fairly regular rate, approximately one centimetre (0.4 inches) per month, so a timeline of exposure can be built up by sequential analysis of strands of hair. It also means that the hair of a corpse lying in fluid containing arsenic will soak it up like a sponge, and store it; this results in higher concentrations in the hair than in the fluid. During post-mortem examinations care had to be taken that hair on the corpse was not allowed to come into contact with fluid from the body in case it artificially raised the arsenic level in the hair, giving the impression of long-term exposure. In cases of exhumation the same care had to be taken when removing the body from the ground, and samples of soil from around the burial site had to be collected and analysed.

In the Victorian era, cases of arsenic poisoning became difficult to prove, and the potential complexity of the situation is illustrated by the Maybrick case. In 1889, 50-year-old James Maybrick fell ill with stomach pains and violent vomiting. His 26-year-old American wife, Florence, nursed him devotedly. The couple had recently made up after a violent falling-out over a liaison Florence had had with a friend of her husband. James had also had a string of affairs, but it was Florence's infidelity that resulted in her getting a black eye, and he cut her out of his will. James was something of a hypochondriac, and took a lot of patent medicines to treat himself. During his last illness James asked his wife for his powders, and Florence added some to a bottle of meat juice for her husband to drink, as was his usual custom.

This time James got no better. His family soon arrived to see that he was receiving proper medical attention. Florence was not popular in the household after a letter written to her lover was intercepted, in which she had written that her husband was ‘sick unto death', and she was effectively banished from the sick room. When James subsequently died a couple of weeks later, suspicion immediately fell on Florence.

At Florence's trial, the prosecution was able to show that she had bought arsenical fly-papers, which she claimed she had intended to use to prepare a tonic for her skin; she had run out of her usual facial wash and had decided to try and make her own. When Florence purchased the fly-papers she also bought a lotion containing benzoin and elderflower water – the usual ingredients for the skin lotion. Soaking a fly-paper in cold water extracted three-quarters of a grain of arsenic (not enough to kill), but boiling water extracted almost all of the arsenic (over two grains, close to a lethal dose), and it also extracted the colouring in the paper. The fly-papers were sold in packets of six and were clearly labelled as poisonous. The quantity of arsenic in each fly-paper varied, but every one of a packet that was analysed for the trial was found to contain enough arsenic for at least one lethal dose.
¹⁹

In fact, Florence Maybrick had no real need to buy fly-papers. There was already plenty of arsenic in the Maybrick household. The police had discovered bottle after bottle of cosmetics and patent medicines in their search of the house, with many containing arsenic. There was enough of the poison to kill 50 people, but there was one place where there was relatively little – inside James Maybrick's body. Medical men were called by Florence's defence to testify that James Maybrick had died of natural causes. No one had witnessed Florence administering arsenic to her husband, and for several days before his death she had no contact with her husband, his food
or his medicines. The jury, however, thought there was enough evidence to convict her and found Florence guilty. Her death sentence was commuted to life imprisonment because doubts remained over whether James had died of arsenical poisoning, rather than whether it was Florence who had poisoned him. Florence protested her innocence throughout the 14 years she was imprisoned, and after her release appears to have led a blameless life.

When Agatha Christie began her writing career, arsenic compounds could still be obtained relatively easily in the form of medicinal ‘tonics', pesticides and weedkillers, but arsenic was slowly phased out of use over the first half of the twentieth century as alternatives were found for rat poisons and herbicides. Some specialist industrial uses remain, though, but there is only one remaining medical use for arsenic trioxide, for the treatment of acute promyelocytic leukemia. However, this treatment is not without risk from arsenical poisoning.

How arsenic kills

The toxicity of arsenic trioxide and related compounds stems from their disruption of basic chemical processes within the body. Arsenic compounds are readily absorbed through the skin, lungs and gastrointestinal tract, and most poisoners have exploited this by adding arsenic to food, drink or medicines.

Arsenic compounds occur in two forms, arsenates and arsenites, and they interact with the body in different ways. Arsenates (AsO
4
3-
) are structurally and chemically similar to phosphates (PO
4
3-
) and the body is unable to distinguish between the two. Phosphates perform many vital roles in biology, from strengthening bones to forming the backbone of DNA's double helix. These chemical units are also involved in vital chemical processes within cells, one of the most important of which is the transfer and storage of energy. In the home, electricity is the form of energy we use to power our gadgets and appliances. Inside the body, energy from the food we eat and oxygen we breathe is used to produce a
chemical called adenosine triphosphate, or ATP. The transfer of phosphate units from ATP to other molecules makes them chemically more reactive, and allows reactions to occur under the relatively mild conditions experienced in most biological systems. Arsenate compounds kill because they can substitute for phosphate in ATP. Arsenate is less chemically reactive than phosphate, and consequently the chemical reactions it is involved with are slowed and may even stop – and this is very bad news.