Books laced with arsenic removed from French national library

Reading hall of the National Library of France in Paris  (Alamy)
Reading hall of the National Library of France in Paris (Alamy)

Four 19th-century books suspected to contain arsenic, a poisonous substance, in their covers have been removed from France’s national library, the Bibliothèque Nationale de France in Paris.

The books – believed to contain arsenic because of their emerald green covers – were identified by University of Delaware researchers and include works like the 1862-1863 book of the Royal Horticultural Society and two volumes of Edward Hayes’s “The Ballads of Ireland” from 1855.

The Poison Book Project, a joint effort by the University of Delaware and the Winterthur Museum of Delaware, flagged these titles among others due to concerns about arsenic used in Victorian-era book bindings.

The National Library of France has now quarantined these books for analysis to determine the level of arsenic in the covers.

“We have put these works in quarantine and an external laboratory will analyse them to evaluate how much arsenic is present in each volume,” the library said in a statement.

Similar precautions have been taken in Germany while a book containing arsenic was found in a Leeds library in 2022.

Melissa Tedone, a conservator at the Winterthur Museum, told Discover magazine in 2022: “At the time, emerald green was the most colourfast, brilliant green colourant available and it was a wildly popular colour among consumers. No alternative dye could even come close to the intensity of the colour.”

Given its application during an era characterised by both big and small binderies employing machinery, Ms Tedone said that tens of thousands of books were bound in emerald green between the 1840s and 1860s.

In 2019, Tedone and her colleagues started testing on hundreds of books from Winterthur and the Library Company of Philadelphia and found that half of the books had lead content, while others showed traces of various heavy metals like chromium and mercury.

Slightly over 10 per cent were identified to contain arsenic-laced emerald green, which poses a significantly higher health risk to librarians, collectors, and researchers.

“The arsenic offset is invisible to the naked eye,” Ms Tedone explained, “so a person handling an arsenical book wouldn’t necessarily see any green pigment offsetting onto their hands or other surfaces.”

The World Health Organization warns against long-term arsenic exposure but doesn’t provide specific guidelines for handling arsenic-laced items.

The Poison Book Project states on its website that the “ongoing investigation explores the materiality of Victorian-era publishers’ bindings”.

“Research focuses on identifying potentially toxic pigments used in bookbinding components and how to handle and store potentially toxic collections more safely.”