What is arsenic?

Arsenic is an element in the heavy metals category. Arsenic occurs naturally in the environment and can therefore also be found in food, for example in rice or fish. In the past, arsenic was used in pigments, especially in green paint. Frequent and prolonged contact with arsenic is potentially harmful to health.  

Does the KB have any books containing arsenic in its collection?

Yes. Arsenic was regularly used from the Middle Ages until about the mid-nineteenth century to make the colour green. Schweinfurt green (also called Paris green or emerald green) was extraordinarily popular in the first half of the nineteenth century. In that period, and also before, arsenic-based paint was used to decorate book bindings, for example. The KB has books from both this period and earlier. Through our own research, we know that the KB has books in its collection that contain arsenic.  

How many collection pieces does this concern?

It is very difficult to determine how many items in the KB collection contain arsenic. We took a sample, based on a preselection with works in which we suspected arsenic had been used. We know that arsenic was frequently used in the period up to 1900, and especially in the 19th century. The KB has at least half a million books and other items from that period. We then conducted tests on about 1,000 volumes, which showed that arsenic could indeed be detected in about 30% of the cases. We are still looking for a method to conduct research on a larger scale.        

How can KB staff work safely with this collection?

The KB has established a safety protocol for staff who handle collection items containing arsenic. The material can be handled safely when hygiene measures are taken. When handling these books, our staff are required to use nitrile gloves and an FFP3 mask. Surfaces that come into contact with arsenic-containing collection items are also cleaned more frequently and thoroughly. This provides sufficient protection to work with the material. After handling the books, you must wash your hands and dispose of the protective equipment safely. 

Can KB customers safely handle these books?

Customers are only allowed to view collection pieces that contain arsenic if they follow the protection protocol. The desk staff explain the protocol to customers who want to view a book containing arsenic. The book is packaged in a special box. The customer is also given protective equipment along with the book. If a customer does not want to use this protective equipment, the book will not be distributed. After the collection piece is viewed, it must be packed back into the special box and the protective equipment disposed of properly. 

Besides the use of personal protective equipment, what safety measures have been taken?

Collection items suspected of containing arsenic have been removed from the reading rooms and have been or are being tested. Collection items that have been tested and found to contain arsenic are packed in a box that we mark clearly. Directly affected employees have been or will be informed. All collection items tested are given a physical marking, even if the test was negative. (This marking is As+ or As-). In addition, we are working on adding entries in the catalogue in cases where arsenic has been detected in a work. Areas where collection items containing arsenic have been handled are cleaned afterwards.  

I also have old green books at home. Can I test whether my books contain arsenic myself?

Testing for arsenic should be done in a laboratory setting with a specific chemical test or with advanced analytical equipment. Those who suspect the presence of arsenic-containing paint in their own books are advised to wear nitrile gloves and a mask while handling these books, and to wash their hands thoroughly with soap and clean the table properly after use. 

Can the KB test whether my books contain arsenic?

Unfortunately, no. The KB is still in the process of identifying the presence of arsenic in its own collection. To do so, using specialised tests, we need all our available people and resources. 

Which steps is the KB taking now?

Because of its proactive stance around this research question, the KB has gained knowledge that other parties in the heritage network can benefit from. As the KB regularly receives questions about this matter, we would like to work with our network partners to share and increase knowledge. These partners include libraries, archive and record offices and heritage institutions with natural history collections - in the Netherlands and abroad. We consider this broader research necessary, but it requires people and resources. The KB is currently investigating how to engage in large-scale research and knowledge sharing with regard to arsenic.