A collaborative approach to heavy metals in the collection

What was once a popular pigment now poses an unexpected challenge for heritage institutions. Arsenic, for instance, was historically used to create the colour green, a popular choice for decorating bookbindings and book edges, among other things. The peak of this practice occurred in the mid-19th century.

This means that arsenic and other heavy metals are likely to be found across various collections. The topic has rapidly become a matter of international attention. For this very reason, it is essential to increase knowledge about hazardous substances in collections and to provide clear information on existing basic safety measures.

To map out this issue within the Boekentoren, we, as the university library, drew upon the expertise available within Ghent University (UGent) and the Archaeometry and Natural Sciences Research Unit.

Five Master's students in Archaeology completed an internship at the Boekentoren and assisted in the random sampling and analysis of the collection using a mobile XRF device. XRF, or X-ray fluorescence spectrometry, is a technique where the chemical composition of a sample, in this case a book from the collection, is determined using X-ray fluorescence. This technique is non-destructive, meaning the book is not damaged by the analysis. It is a method commonly used for older manuscripts and books.

During this exercise, we see that arsenic, as well as other heavy metals such as lead, are easily detected by this technique. The results of this internship will subsequently be thoroughly analysed as part of the students' research placements. In this way, we will gain a clearer insight into the presence of heavy metals within the collection.