After the Industrial Revolution, books gradually became more widespread, with people adding bright colors to book covers or content to increase their visual appeal and artistic value. However, these colorful paints contain toxic substances that could potentially lead to respiratory diseases, cancer, or other health issues. Scientists urge people to check 19th-century published books to see if they contain these substances.
In the past, many books in Europe and America were made with leather covers, making them relatively expensive and not affordable for everyone. It wasn’t until the Victorian era (early 1800s) that publishers began mass-producing books with green-dyed covers instead of leather after the first Industrial Revolution, aiming to attract customers and reduce costs to make books more affordable.
These compounds, known as Paris green, emerald green, or Schweinfurt green, contain arsenic, which was created by German chemist Carl Wilhelm Scheele in 1775 by mixing copper and arsenic (arsenic trioxide).
Although these greens are vibrant and captivating, when they come into contact with sulfides in the air, they turn black and are eventually discarded. Subsequently, publishers turned to more durable colors like emerald green and Paris green dyes, using them for book covers, clothing, candles, wallpaper, and house paint.
In the decades following the discovery of emerald green and Paris green dyes, reports emerged of people dying from prolonged exposure to dye-coated items. These reports included cases of poisoning at Christmas parties from green candles, formal wear at green ballroom events, and industrial workers experiencing toxicity after painting ornaments.
For over 150 years, these toxic books have been commonly found in libraries across Europe and America, mixed in with a large number of books in institutions worldwide. Whenever these toxic books are discovered, they are placed in isolated environments for further analysis by scientists.
Currently, scientists worldwide have discovered hundreds of old green-covered books containing arsenic compounds, including “The Poems of William Cowper” “Liberty Bells” and “The Wreath of Summer Flowers.”
The National Library of France removed four books with emerald green covers containing traces of arsenic in April this year. Although trace amounts of arsenic do not pose serious harm to the human body, the library is conducting more tests to ensure their safety before considering returning them to the shelves.
These four books are: “The Yearbook of the Royal Horticultural Society” (1862–1863), Edward Hayes’ “Irish Melodies” (two volumes) from 1855, and Henry Stanley’s bilingual “Romanian Poetry” selection from 1856.
A library spokesperson said, “We have isolated these works and are analyzing them in external laboratories to assess the arsenic content in each book.”
Researchers at the University of Delaware collaborated with Delaware’s Winterthur Museum in 2019 to launch the Poison Book Project, testing hundreds of covers for lead, arsenic, chromium, and other heavy metals content in hopes of cataloging potentially harmful books into a library project for observation and discovery.
The discovery of these toxic books came from Melissa Tedone, a curator at the Winterthur Museum in Delaware. While trimming a book’s spine and boards, she unexpectedly saw green paint flaking off the book cover. The paint seemed to sit on the surface of the book fabric instead of penetrating the textile fibers, forming a thick coat on top.
She then subjected the covers of these books to X-ray fluorescence spectrometry and Raman spectroscopy to check for other substances in the dye. The results confirmed the presence of arsenic in the dye. Furthermore, red and yellow covers contained varying levels of mercury and lead.
Tedone stated to the Canadian Broadcasting Corporation (CBC), “I know wallpaper has arsenic pigments, and I knew illustrations in books contain arsenic pigments, but you don’t think poison is on the cover of the book you pick up to read. While we haven’t found any cases of serious illness resulting from handling such books, we want to raise awareness of the potential danger to prevent unnecessary tragedies.”
She mentioned they are examining all potential toxic components in the book fabric. Additionally, they are documenting all large-scale manufactured binding books from the 19th century, as they might contain a certain type of arsenic compound.
Experts at the Museums Victoria’s library reminded that toxic books may exist in libraries or homes. While handling old books may not immediately harm individuals, precautions should be taken to protect oneself from chemical substances. It is advisable to wear gloves when handling books and wash hands immediately after handling.
Furthermore, any toxic books found should be placed in plastic casing to prevent toxin flaking from the book and handed over to experts for proper handling.
Library manager Hayley Webster stated, “Traditionally, books were considered quite safe items, but I think there is a lot to learn now because there are many things we don’t know.”
She explained several conditions for the release of toxic substances on books. She mentioned, “Books dyed with toxic fabric
require some abrasion or moisture for harmful substances to be released, posing a real threat to the body.”
Previous studies have found that arsenic exposure is associated with increased respiratory symptoms, poor lung function, and chronic lung diseases. Long-term exposure may also lead to skin damage and cancer.
Additionally, during book testing, it was found that some books with red dye embossing contained vermilion, a red mineral containing mercury sulfide. Vermilion ranks among the top three toxic substances in the list of the Centers for Disease Control and Prevention in the United States.
Material scientist Rosemary Goodall, who identified toxic substances in the collection, found that out of 120 tested books in the museum, four contained arsenic, and the other 110 books had excessive lead content. She mentioned, “But high concentrations can lead to severe headaches, delirium, coma, brain damage, and possibly death.”
Moreover, it was discovered that yellow-colored books with trace amounts of lead chromate had a certain level of toxicity. Fortunately, the solubility of this yellow dye is very low, making it unlikely to be absorbed through touching the cover.