In the later years of his reign, the first Emperor of China, Qin Shi Huang, was terrified of the looming spectre of death and sought a way to prolong his life.
He began the quest for immortality, frantically sending his courtiers out to search for a so-called elixir of life and commanding alchemists to produce one before he expired.
In a twist of irony, what he believed would keep him alive would instead be the death of him, as one of the supposed elixirs he consumed contained high levels of mercury.
Quite disturbingly, the usage of mercury in alleged elixirs of life would continue on even in later dynasties and would unsurprisingly cause the deaths of many emperors.
However, historically, mercury is not the only metal that humans have been using carelessly without realising the level of danger they pose.
Marie Curie and her husband, Pierre, discovered radium on Dec 26, 1898 and even before the dangers of radiation were truly understood, Pierre stated he would not want to be left in a room with pure radium as it would likely burn, blind and kill him.
He was not off the mark about the danger of radium but unfortunately, for the rest of the world, this glowing green metal was a new plaything and a wondrous chemical.
It was used to flavour water and stuffed into toothpaste, jewellery, medicine and beauty products; with advertisements lying about the metal’s medical benefits.
Rather horrifyingly, during the First World War, female factory workers in American factories were exposed to radium’s radiation as they painted watch dials with self-luminous paint.
The process involved them using their lips to make the brush pointy, which resulted in them ingesting radium in the process.
In the long run, many of the women suffered lethal injuries, with their jaws crumbling and spines destroyed; the radium inside was drilling holes in their bones.
Lead has been used since antiquity, with the ancient Greeks and later, the Romans, using it to make white paint.
However, toxicity does not change throughout the centuries, and even now, lead has had terrible effects on the human body.
As it is absorbed by the body, it enters the bloodstream and tissues.
Once inside, it mimics and messes up the role of calcium, resulting in a whole host of health problems, ranging from high blood pressure to learning disabilities.
Despite the danger, lead continued to be an item in the artist’s inventory up to the 19th century as it was used to make tempera paint.
Many unlucky artists would suffer from lead poisoning, but lead paint’s incomparable qualities meant that it would be used until bans were imposed in the 20th and 21st centuries.
Another deadly element used since ancient times, arsenic is not necessarily lethal in minuscule doses, but excessive contact is indeed lethal.
A compound containing arsenic, cupric hydrogen arsenic, was present in two paints introduced in the 18th century, namely Paris Green and Scheele’s Green.
These new green paints were more vibrant than the duller greens made from natural pigments, and thus, they were used in paints, food, soaps and clothing.
Exposure to arsenic causes damage to the function and communication of human body cells and high exposure can result in cancer and heart disease.
The consequences of frequent usage of these arsenic-laden paints were deadly, with 18th century textile workers suffering from poisoning. There were also reports of women dressed in green collapsing.
Bed bugs were said to stay away from rooms coloured green and there is even a theory that while in exile on St Helena, Napoleon Bonaparte died from slow arsenic poisoning, his bedroom having green-coloured wallpaper.
The true toxic nature of the paints was only exposed in 1822 and rather tellingly, a century later, they were used as pesticides instead.