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Researchers Accidentally Discover That Rare Books Are Poisonous

Rare manuscripts can be fascinating to study, but when it turns out that the material of said manuscripts can be poisonous, well things can get a bit awkward. [Warning: Graphic photo below]


A Research Librarian and Professor of Physics at the University of Southern Denmark accidentally discovered that three rare books they were studying were in fact poisonous. In an article published by The Conversation, the duo described their surprising findings. While using X-ray technology to try to decipher the the text on the bindings of the 16th and 17th century manuscripts (older manuscripts used recycled parchment), the researchers found high levels of green arsenic on the covers. 


The findings came as a shock, especially regarding the volatile effects of arsenic. As the duo notes, exposure to the extremely toxic chemical can lead to, “various symptoms of poisoning, the development of cancer and even death.” 



arsenic effects

Image included by research team shows effects of green arsenic | Image Via Wellcome collection



Though it now widely known that arsenic poses significant harm to those exposed to it, centuries ago it was used quite regularly in paints, clothes, book covers, and even applied to wallpaper as a protective layer. 


While the use of green arsenic in wallpapers and materials seems to be left in the past, the horrifying stories of its effects are still being discussed today. As for the arsenic-laced books at the University of Southern Denmark, they are now being kept separate from the other books in the library and stored in operate cardboard boxes with “safety labels in a ventilated cabinet.”


Though readers may assume that manuscript pages are safe to handle, it isn’t always a guarantee, the team notes.


“One wouldn’t expect a book to contain a poisonous substance. But it might.”




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