Poisonous Pigments: Scheele’s Green

Have you ever stopped to wonder where your paints came from? The history of pigments has a vast and fascinating history that ranges from natural extractions to synthetic discoveries. But even as natural or synthetic extracts, some pigments can’t escape the harmful elements that can eventually lead to someone’s death! With this, I think it’s important that I share with you some of the history’s most poisonous pigments just in case you find yourself with a can of paint labeled “Lead White” one of these days.

Because there is a wide variety of these poisonous pigments, I have decided to focus on one specific color each week and go into detail of its deadly upbringings and usages. For my first post, I will discussing the pigment that some have labeled as the “Invisible Killer” – Sheele’s Green.

Scheele’s Green

 

Chemist Carl Wilhelm Scheele from Svenska Familj-Journalen 1874.

This color was invented in 1775 by Carl Wilhelm Scheele, who was a Swedish chemist. It was an artificial colorant that was made by heating up sodium carbonate, adding arsenious oxide, and stirring until the mixture was dissolved. Copper sulfate was then added as the final solution which ends up giving it its vibrant green color. According to color historian Victoria Finlay, Scheele invented this green “almost accidentally.” A year before the color went into production, he wrote to a friend that he thought users might want to know about its poisonous nature. “But what’s a little arsenic when you’ve got a great new color to sell?” Finlay tells us.

The vivid green used in Victorian wallpaper was derived from toxic copper arsenite. CREDIT: JOHN TODD MERRICK & COMPANY, LONDON, UK, 1845/2016 CROWN COPYRIGHT, THE NATIONAL ARCHIVES, KEW.

The coloring was cheap and easy to make, so it quickly began to replace the older green pigments and was used in a variety of daily products ranging from children’s toys to home furnishing. Other names the color was called were Paris Green and Emerald Green. So why was this color so poisonous? In case you didn’t pick up what the key ingredient was – Scheele’s green was loaded with copper arsenite, one of the deadliest elements to have ever been discovered.

Accidents caused by the use of green arsenic, 1859.

I won’t go much into detail about what the side effects of arsenic poisoning are (I’ll just let you analyze the picture above for a bit), but arsenic is a highly toxic substance that causes skin lesions, vomiting, diarrhea, and in some cases, cancer. So of course, the 1800’s was riddled in this substance. You could find this arsenic-laced color in candy, paper, toys, and medicine. It was also used as a dye for clothing and accessories, even as far as colorant for the leaves of flowers to make them look more alive and vibrant.

But perhaps one of the most interesting things about this color is that it has been rumored to have killed the famous Napoleon Bonaparte.

Scheele’s Green for Light Grey Art Lab’s Color Anthropology show. Art by Lily Nishita.

After being handed his final defeat by the Duke of Wellington, Napoleon was sent to exile on the tiny South Atlantic island of St. Helena in 1815. During this time, we know that he stayed in a very luxurious room painted with his favorite color – green. Six years later he died of what was most likely stomach cancer, although some speculate it might have been ulcers. Analysis of his hair samples, however, have revealed significant amounts of arsenic. But how can these wallpapers kill someone who was once the most powerful man in Europe? There are two theories: one is that tiny flakes of the paint can break off the wallpaper and become airborne that can therefore be absorbed by the lungs. Alternatively, toxic gases can be released when the compounds undergo certain chemical reactions when exposed to heat and moisture. This means that when wallpaper becomes damp or moldy, the pigment undergoes a chemical reaction which causes the release of poisonous arsenic gasses into the air. Since St. Helena has a humid climate, it is possible that fungus grew of the walls of his home.

It is crazy to think that a color so vibrant and beautiful was also the cause of death to some people. But those were the old days, now you don’t have to worry about a green dress killing you.

Illustration by Rachel Vermeer.

0 replies

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Leave a Reply

Your email address will not be published. Required fields are marked *