It seems creepy now, but it was once commonplace to make decorations out of human hair. The hair—usually a lock cut from a friend, sweetheart, or family member (sometimes a dead one)—was weaved into intricate ornaments, home décor, and even wearable pieces like jewelry and buttons. Not only would people collect the hair of loved ones, but the tresses of the famous were also coveted (Fun fact: Elvis has the most expensive hair). When Napoleon Bonaparte died of cancer in 1821, locks of his hair were sold to those who wanted a memento of the infamous Frenchman. Almost a century-and-a-half later, a lock of Napoleon's hair was chemically analyzed. To the researchers' surprise they found arsenic. Lots of it.
Years before Napoleon's death, a chemist named Carl Wilhelm Scheele was experimenting with copper and arsenic when he developed an intense emerald-green pigment. Despite its abundance in nature, green had been a notoriously difficult colour to reproduce. The intensity of Scheele's green, its relatively inexpensive production cost, and its lasting colour quickly made it a sensation—despite its poisonous ingredient. It was used in everything from carpeting to clothing to confectionery. In one particularly sickly account, a London chef used a food dye of Scheele's pigment to make an amazingly green dessert. Later, three dinner guests died.
Scheele’s Green was especially popular in wallpaper. It was noted as being mysteriously good at keeping vermin and insects away (surprise, surprise). As the wallpaper flaked, the arsenic particles would fill the air and be inhaled by unsuspecting residents. There are reports of children dying after their rooms were painted in the vibrant green, decorators having convulsions, and a cat developing strange blisters after being locked in a green-papered room. Napoleon's bedroom in St. Helena, where he was exiled until his death, had a white, gold, and green wallpaper. Testing in 1980 confirmed that the green and gold fleur-de-lis pattern contained arsenic. The humid air of the tropical St. Helena Island could have created mold that reacted with the wallpaper—creating a poisonous gas that perhaps pushed the defeated ruler to his ultimate demise. Then again, more recent research is skeptical of this toxic gas theory.
Scheele knew that his pigment was deadly. In 1777, one year before it was ready for production, he wrote to a fellow scientist that he was concerned and felt that people should be warned of its harmful potential. The Swedish chemist had made many discoveries throughout his career, including oxygen (reportedly before Joseph Priestley published), citric acid, tungsten, hydrofluoric acid, hydrogen sulfide, and a process to mass-produce phosphorus that lead to Sweden becoming a world-leading producer of matches. Reportedly having a bad habit of tasting and smelling his new—and often hazardous—discoveries, Scheele grew ill with kidney disease and developed a serious skin condition. He died at the age of 43 from mercury poisoning, less than 10 years after he wrote that foreboding letter to his friend.
By the end of the 19th century, it was widely accepted that arsenic wallpapers were hazardous, yet many countries were slow to ban them. It was big business; in Britain alone, it was estimated that there was 100-million square miles of it. In addition to Scheele's Green, other colours utilized arsenic to make vibrant colours. The potential loss of revenue had some wallpaper manufacturers offering to eat pounds of their product to prove it was not harmful. William Morris (a highly influential figure in design history associated with the British Arts & Crafts Movement) referred to the anti-arsenic reports as a foolish scare. His response is perhaps not that surprising considering Morris happened to own shares in his Father's Arsenic mine in the 1870s. Nonetheless, a society once infatuated with Scheele's Green grew to fear it. For the most part, it was the public's own boycotting of arsenic pigments that eventually convinced manufacturers to produce arsenic-free alternatives.