It is not yet possible to say whether and how many of the books actually contain arsenic. The ULB is currently examining with the University Administration, Occupational Safety and Environmental Protection Unit, how the separated holdings can be reliably tested for arsenic and - if uncontaminated - made accessible again. The University of Bonn has been dealing with this issue for some time and has taken early measures to safeguard the situation. Closures and lockdowns, as reported by other locations, are therefore not necessary.
Last year, our experts, in collaboration with the German Library Association's (dbv) Conservation Commission, developed an Action papier (in German).
The topic mainly concerns books from the 19th century. At that time, arsenic-based dyes were very common. The most prominent example is the "Schweinfurt Green". For this reason, potentially arsenic-containing volumes from the 19th century are generally no longer added to the University's collection. In addition, book cuts of books from the 16th-18th centuries can also be contaminated with auripigments (arsenic-sulphur compound). The cuts often have a dirty, muddy appearance.
Arsenic can be harmful to health if, for example, it is ingested in the form of dust or transferred to food via the hands and then swallowed. According to current knowledge, the mere presence of books on shelves or in stacks is harmless. Air measurements carried out at the ULB have also shown no arsenic contamination.
If you have any questions, please contact the Occupational Safety and Environmental Protection Unit (arbeitsschutz@verwaltung.uni-bonn.de) or ULB (hl@ulb.uni-bonn.de).