Identification, transformations and mobility of hazardous arsenic-based pigments on 19th century bookbindings in...

This study focused on the non-destructive characterization of potentially hazardous Victorian-era books found in the Northwestern University Libraries. XRF, Raman and FTIR were used to identify and isolate hazardous books containing As-based pigments. These techniques also permitted, on selected books, to characterize the pigment as being Emerald green. However, none allowed for the identification of equally hazardous degradation products or potential transfer to adjacent books. These analytical gaps create limits in thoroughly identifying the level of risks associated with these books for library users and hampered the application of effective risk mitigation measures. Such limitations were overcome with synchrotron radiation (SR) techniques. Through SR-XRF, Cu/As distributions were mapped across covers and spines of green and neighboring books, whereas SR-X-ray absorption near edge structure (SR-XANES) was used to characterize the As oxidation state, leading to the identification of arsenates as degradation products. Besides successfully identifying hazardous books, this study demonstrated that hazards extend beyond As-containing green books to innocuous, long-standing neighboring books and non-colored pages due to migration and transfer of pigment and degradation products. Aside from helping to implement workplace health and safety measures, this study also informs how other libraries can identify and characterize potentially hazardous items in their collections.