Four books have been removed from France’s national library over concerns that their covers were covered in poisonous arsenic.
The 19th century volumes, printed in Britain, have emerald green covers. At that time, arsenic was commonly used to color book covers, writes the BBC.
Researchers at the University of Delaware identified books taken off the shelves as potentially dangerous.
The library, however, said the books could only cause minor damage if they were flipped.
“We have quarantined those books and an external laboratory will analyze them to assess how much arsenic is present in each volume,” said a spokeswoman for the National Library of France.
The four books also include an 1862/63 Royal Botanic Society work, two volumes of Edward Hayes’ Irish Ballads from 1855, and Henry Stanley’s 1856 bilingual anthology of Roman poetry.
The list of potentially dangerous titles was compiled by the Poison Book Project. That initiative is managed by researchers from the University of Delaware, in cooperation with the Delaware Winterthur Museum.
Since 2019, the team has examined hundreds of book covers for the presence of heavy metals and created a list of titles that are potentially dangerous.
Four copies from the list are among the 16 million books of the National Library of France.
Victorian-era publishers used arsenic to color book bindings, in the pigments Paris Green, Emerald Green, and Schiele Green, named after the German chemist.
The Poisoned Books Project said that poison-laced books should be carefully stored, and could pose a health risk to those who come into their hands.
In response to the poisoned books found, the National Library of France said it would examine other books beyond those examined by the Delaware researchers.
The World Health Organization warns against long-term exposure to arsenic from drinking water and food, stating that the substance is “highly toxic in its inorganic form.” They don’t have any special advice on how to deal with items that contain it.
A rare book with traces of arsenic was found in 2022 in a Leeds library: My Own Garden – A Young Gardener’s Yearbook from 1855, which also had a bright green cover.
