Arsenic is a naturally occurring element with a chequered past. From treating ulcers to bumping off rivals, David Jesudason charts how the chemical has been used to cure and kill for centuries.
Mass murder and marvellous medicine
Words by David Jesudason
- In pictures

The Greek physician Hippocrates discovered the toxic properties of arsenic in 370 BCE but also realised the chemical element could be used to treat ulcers. (He recommended such sores were washed with wine before being dressed with fig leaves, too.) Later, the Roman physiologist Galen (129–99 CE) used arsenic for treating psoriasis.

James C Whorton, writing in ‘The Arsenic Century’, explains that the element was advantageous to those “contemplating murder, as it has no distinctive taste or smell”. One of the most famous early cases of arsenic being used in this way was by the Roman Emperor Nero. Together with his mother Agrippina, he reputedly used white arsenic to murder 13-year-old Britannicus in 1 CE. Nero would probably have assassinated his stepbrother by dissolving the undetectable solution in water before adding it to his food or drink.

Professional poisoners were common in the 15th century. Their skill lay in an ability to concoct toxins that didn’t lead to an immediate or obvious death. The Borgia family were known for this method of assassination and used a compound of arsenic called cantarella, which caused weakness, confusion, vomiting, diarrhoea and intestinal pain. Lucrezia Borgia, born in 1480, was infamous for using cantarella to kill rivals and those she couldn’t manipulate. However, her reputation as a femme fatale was probably overstated by her own family, who used her notoriety to gain power in Renaissance Italy.
Guilia Tofana became notorious after selling arsenic to wives who wanted to murder their husbands in 17th-century Italy. She is believed to have helped kill 600 men by dispensing her arsenic-laced Acqua Tofana under the guise of a cosmetic lotion. It took effect very slowly and was believed to bring about death on a predetermined day. Wolfgang Amadeus Mozart, who died in 1791, is perhaps the most famous Acqua Tofana ‘victim’. Some reports claimed that he was poisoned by rival and teacher Antonio Salieri, a myth perpetuated by Alexander Pushkin’s ‘Little Tragedies’ dramas.

Arsenic poisonings were common across the whole of Europe, particularly in France. Between 1677 and 1682, the Affair of the Poisons rocked French society when members of the aristocracy were charged with poisoning and witchcraft during the reign of King Louis XIV. But arsenic wasn’t only used for murder; it was also used in consumer goods. It can produce a bright green pigment, which might explain why, after his death, Napoleon’s hair was found to contain abnormal quantities of arsenic: it reputedly came from a type of wallpaper he liked.

Arsenic became popular in Victorian Britain as a cheap ‘replacement’ ingredient used in everything from wine and beer to children’s sweets. The Arsenic Act of 1851 placed restrictions on its use, making it the UK’s first legally recognised poison, but enforcement of the law was weak. In fact, 21 people were killed and over 200 poisoned in the Bradford sweets poisoning in 1858. Arsenic was also used in cosmetics well into the 20th century, with many people accidentally poisoned.

Despite the number of deaths it caused, accidental or otherwise, in 1909 arsenic once again became a force for medical good. German chemist and Nobel Prize-winner Paul Ehrlich perfected a chemical compound to treat syphilis called Salvarsan. It contained 30–32 per cent arsenic and was a ‘magic bullet’ that could locate and destroy invading pathogenic cells. The principles of how Salvarsan works, where a compound seeks out and destroys diseased cells, only causing minor damage to the patient, was new and soon to be used in chemotherapy.

Not all technological advancement benefits humanity, and during World War I arsenic caused huge amounts of suffering. During the Battle of Verdun, in 1916, about 300,000 people died in 303 days. Many of the estimated 23 million shells used were filled with arsenic, and fields in this region of France remain poisoned today. Later, the chemical weapon lewisite was developed, which included arsenic trichloride among its ingredients. Lewisite causes skin to blister and has the nickname ‘Dew of Death’.

Arsenic’s notoriety means it has featured in a lot of fiction. It’s strongly associated with Agatha Christie, although only eight of her characters are killed with arsenic out of a total 300 victims. Frank Capra’s ‘Arsenic and Old Lace’ stars Cary Grant as a drama critic who discovers his aunts are poisoning their lodgers. But perhaps the most memorable arsenic death is in ‘Madame Bovary’. As Joan Acocella writes in the New Yorker, “Flaubert described the process in detail: the retching, the convulsions, the brown blotches breaking out on the body, the hands plucking at the bedsheets. He is said to have vomited at the dinner table two nights in a row after writing this scene.”
About the author
David Jesudason
David Jesudason is a freelance journalist who covers race issues for BBC Culture, Pellicle and Vittles. He was named Beer Writer of the Year in 2023, after his first book ‘Desi Pubs, A Guide to British-Indian Pubs, Food and Culture’ was hailed as “the most important volume on pubs in 50 years”. David also writes ‘Pub Episodes of My Life’, a weekly newsletter about the drinking establishments that serve marginalised people.