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What is arsenic? -

Arsenic is a naturally occurring chemical element in the environment. It exists in both gray and yellow crystalline forms and is found in several minerals, usually in combination with sulfur and metals.

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Albertus Magnus (c. 1200–1280) -

German Dominican friar, philosopher, scientist, and bishop Albertus Magnus is generally credited with the discovery or arsenic, around 1250.

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Paracelsus (c. 1493–1541) -

But it was the Swiss physician and alchemist Paracelsus who recorded the first precise directions for the preparation of metallic arsenic.

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Cesare Borgia (1475 –1507) -

Poisoning had already been proven as crude but effective method of murder in antiquity. By the Middle Ages, however, it had evolved into a fine art form, with the Borgias the most widely accused poisoners. Cesare Borgia especially was considered a master of "applied toxicology."

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Medicinal use -

Arsenic's legitimate use during the medieval period was as a medicine. Its compounds were used for the treatment of such diseases as psoriasis and syphilis. It was also used to alleviate skin ulcers and joint disorders.

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Odorless and tasteless -

But applied for nefarious reasons, arsenic was deadly. The odorless and tasteless properties of inorganic arsenic compounds such as arsenic trioxide (white arsenic) made them an ideal poison. The white crystalline powder was soluble in water and virtually undetectable in food or drink. Would-be murderers took note!

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Angel Makers of Nagyrév -

Modern history's most notorious case of arsenic poisoning is that of the so-called Angel Makers of Nagyrév. These were a group of seemingly inoffensive women living in the village of Nagyrév, Hungary, who, between 1914 and 1929, poisoned to death an estimated 40–100 people.

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Angel Makers of Nagyrév -

The Angel Makers were supplied arsenic and encouraged to use it by a local midwife named Zsuzsanna Fazekas. Pictured are defendants exercising in the Szolnok prison yard after the murder ring was exposed.

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Angel Makers of Nagyrév -

The murders were made public in 1929 after authorities had exhumed dozens of corpses from the local cemetery. All victims were found to have succumbed to prolonged arsenic poisoning. Some of the Angel Makers are pictured as news of their crimes came to light.

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Frederick Seddon (1872–1912) -

The case of Frederick Seddon became a cause célèbre in England. Seddon, who was obsessed with money, was arrested in early 1912, charged with murdering his lodger, Eliza Mary Barrow, after persuading her to sign over to him a controlling interest in all her savings and annuities. Seddon is pictured arriving at court.

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Tollington Park arsenic case -

In what became known as the Tollington Park arsenic case, Seddon was accused of killing Barrow using, of course, arsenic. His wife, Margaret, was also implicated in her death, but was ultimately acquitted of any foul play. Found guilty, Frederick Seddon was hung at Pentonville Prison on April 18, 1912. Pictured is the family of the accused arriving for the court case.

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Arthur Waite (1887–1917) -

Young and dashingly handsome, Arthur Waite was a trained dentist and a playboy. In 1917, he stood trial in New York accused of murdering his father-in-law and mother-in-law, John and Hannah Peck.

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Murder of John and Hannah Peck -

Waite was eventually found guilty of poisoning both using arsenic. The motive was money, with Waite hoping to get his hands on John Peck's lucrative drugs company business. Waite's wife Clara was also poisoned, but later recovered. On May 24, 1917, Waite was executed by electric chair at Sing Sing prison.

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Mary Creighton (1899–1936) -

Mary Creighton, wife of John Creighton, was a piece of work. Both lived with John's parents, Walter and Anna. In 1920, Mary Creighton was suspected of poisoning Anna. The following year, she again fell under suspicion for poisoning Walter. And in 1923, she was accused of poisoning her younger brother, Ray. That year, Mary and John Creighton were charged with Ray's murder. Both were acquitted. The Anna Creighton murder trial, which was held in 1923 as well, also ended with Creighton being acquitted (her husband John was not charged).

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The "Black Eyed Borgia" -

Roll on 13 years to 1936. John and Mary now had a daughter called Ruth. The Creightons had invited into their home Everett Applegate, his wife Ada, and their daughter Agnes. But the home share idea quickly soured. Mary and Everett began an affair. The lovers then conspired to do away with Everett's wife Ada by poisoning her with arsenic. In a murder case as salacious as it was sensational, Mary Creighton and Everett Applegate were found guilty of Ada's murder and sentenced to death. Dubbed the "Black Eyed Borgia" by the press, Mary Creighton and her lover were executed at Sing Sing prison in New York on July 16, 1936.

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The South Croydon poisonings -

On May 18, 1929, the body of Edmund Duff was exhumed at Queen's Road Cemetery in Croydon, South London, for an inquest into his mysterious death from suspected arsenic poisoning. Family members Vera and Violet Sydney had also died under similar circumstances, and were similarly disinterred.

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"South Croydon Poisoner" -

All three were found to have died from arsenic poisoning. Edmund Duff's widow Grace was the primary suspect, but there was insufficient evidence to charge her with any crime. The inquest attributed their deaths to murder by persons unknown. The press, however, concluded that the "South Croydon Poisoner" was to blame, though this proved just a headline-grabbing attempt at sensationalism.

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Madeleine Smith (1835–1928) -

In 1857, Glasgow socialite Madeleine Smith was accused of poisoning her lover with arsenic. In the dramatic trial that followed, Smith was found not guilty of the crime even though toxicological evidence confirmed that the victim had died in this manner. Pictured is the arsenic poison bottle produced as evidence during the proceedings.

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Mary Blandy (1720–1752) -

Englishwoman Mary Blandy was hung in 1752 for poisoning her father with arsenic. During her trial, Blandy claimed she had no idea that the powder she administered to her father's food was arsenic. Furthermore, she insisted it had been supplied by her suitor as a love potion, which he hoped would persuade her father to approve of the relationship. Blandy is pictured wearing leg irons under her dress to prevent her escape.

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Marie Lafarge (1816–1852) -

Marie Lafarge was a French woman who was convicted of murdering her husband by arsenic poisoning in 1840. Lafarge was one of the first defendants in a trial anywhere in the world to be convicted largely on direct forensic toxicological evidence.

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Florence Maybrick (1862–1941) -

Alabama-born Florence Maybrick was convicted in the United Kingdom of murdering her husband, wealthy cotton merchant James Maybrick, in 1889. She was sentenced to death, but this was later commuted to life imprisonment. She was released in 1904 and returned to the United States, still protesting her innocence.

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Harold Greenwood (1874–1929) -

Respected English solicitor Harold Greenwood was accused and acquitted of murdering his wife, Mabel, by arsenic poisoning. The arsenic was said to have been mixed with wine. The killing remains unsolved. Greenwood is pictured on June 16, 1919, arriving at court.

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Herbert Armstrong (1869–1922) -

Another English solicitor, Herbert Armstrong wasn't as fortunate. Armstrong was initially charged with the attempted murder of a professional rival whom he tried to poison with arsenic. He was later also charged with, and convicted of, the murder of his wife by the same means. On May 31, 1922, Herbert Armstrong was hanged.

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Mary Ann Cotton (1832–1873) -

English convicted murderer Mary Ann Cotton was executed on March 24, 1873, for poisoning her stepson. Cotton is believed to have been a serial killer, with the deaths of as many as 17 children, including many of her own, attributed to her. Cotton's preferred method of killing was poisoning by arsenic.

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Kate Dover (1855–1925) -

The case of Kate Dover is remarkable for the fact that her victim, Thomas Skinner, was well known in England for inventing a method by which the mass production of etched designs on steel blades (pictured) could be facilitated by means of paper transfers. After he was widowed, Skinner was secretly given arsenic by Dover, who was his housekeeper. She served time in prison before being released in 1895.

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Masumi Hayashi -

In 1998, a Japanese woman, Masumi Hayashi (pictured head down in a police vehicle), was convicted of putting arsenic in a pot of curry being served at a village festival. Two children and two adults died after consuming the curry, and 63 others suffered from acute arsenic poisoning. Investigators later established that Hayashi had dropped at least 130 g (4.5 oz) of arsenic into the cooking vessel—enough to kill over 100 people.

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Arsenic as a taker of life -

The English writer and poet Thomas Chatterton (1752–1770) took his own life by ingesting arsenic. The poison was commonly used for this method of self-dispatch, swallowed in a large dose for a quick exit.

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Charles Francis Hall (c. 1821–1871) -

The mysterious death of American Arctic explorer Charles Francis Hall in 1871 has intrigued historians. An exhumation of his body in 1968 revealed that he had ingested a large quantity of arsenic in the last two weeks of his life. Did he take his own life, or was he murdered?

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Guangxu (1871–1908) -

Guangxu, the 10th emperor of the Qing dynasty, survived a coup in 1898 that saw him placed under house arrest until his death in 1908, officially declared as being of natural cause. But his passing raised eyebrows, with many believing the emperor had been poisoned. It wasn't until 2008 that modern researchers confirmed the rumor: the nature of Guangxu's death was anything but natural. His body indicated that it contained extremely high levels of arsenic.

Sources: (Oxford Academic) (National Library of Medicine) (Library of Congress) 

See also: History's most notorious poisonings

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