By reading books you acquire knowledge or you can get killed as Alexandra K. Newman recently wrote in a blog post titled “If Books could kill: A Deadly Secret in the Cullman Library” on the homepage of the Smithsonian Library.  The post is about the 1602 edition of Ulisse Aldrovandi’s De animalibus insectis which is part of the Joseph F. Cullman 3rd Library of Natural History.  The green painting adorning the contemporary binding is laced with arsenic.
One of the pig skin corners of the Cullman’s Aldrovandi has been lost, exposing an unpainted section of the recycled manuscript’s text. It is not unheard of that the paint in books bound this way will rub away and reveal the writings of the medieval manuscript.

Ulisse Aldrovandi’s De animalibus insectis (1602) showing the exposed corners of the binding. Source: “If Books could Kill”

The Smithsonian Library conducted a X-ray fluorescence analyses (XRF) of the book. According to Wikipedia X-ray fluorescence (XRF) is the emission of characteristic “secondary” (or fluorescent) X-rays from a material that has been excited by bombarding with high-energy X-rays or gamma rays. The phenomenon is widely used for elemental analysis and chemical analysis, particularly in the investigation of metals, glass, ceramics and building materials, and for research in geochemistry, forensic science, archaeology and art objects such as paintings and murals.
The result of the XRF was that:

… the Cullman’s Aldrovandi was, indeed, covered in paint with a high arsenic content (see analysis below). Reading over the analysis, Kavich speculates that the arsenic comes from the use of orpiment (As2S3), an arsenic sulfide mineral that is bright yellow in color.
This yellow would have been mixed with either Prussian blue (a possibility, given the iron that was also found in the analysis) or an organic pigment such as indigo (which cannot be detected using the XRF method).

Alexandra K. Newman, “If Books Could kill: A Deadly Secret in the Cullman Library”

The arsenic in the paint could accidentally be inhaled or ingested by readers, as the paint crumbles and becomes airborne or sticks to fingers, and arsenic poisoning can cause dizziness, headaches, coma, and even death.

An example of rubbed  away paint in  Omnia quae extant in latinum sermonem conversa. Galen, published Basel, 1561.
Royal College of Physicians (RCP) library collections

For the time being Cullman’s Aldrovandi will remain wrapped in bubble wrap and is not accessible to researchers. The librarians at the Smithsonian Library use Mylar archival bags which will be sealed at the edges. The book will also receive a made-to-measure box to keep it from contaminating its shelf mates.
boPET film (Mylar is the brand name) is used to best protect books and archival materials during storage from environmental conditions (moisture, heat, and cold) that would otherwise cause paper to slowly deteriorate over time. This material is used for archival quality storage of documents by the Library of Congress (specifically Mylar® type D) and several major library comic book research collections, including the Comic Art Collection at Michigan State University. While boPET is widely (and effectively) used in this archival sense, it is not immune to the effects of fire and heat and could potentially melt, depending on the intensity of the heat source, causing further damage to the encased item. (Source)

So we learned that working with rare books can be quite hazardous and not as dull as many people think as I found more examples of rare books which could be poisonous.  So next time you visit the Special Collections of a Library be aware that the book you handle could be poisonous. 🙂