Deteriorating leather bindings and red rot – health and safety considerations

Conservators working with red rot damaged leather bindings sometimes do not use personal protective equipment (PPE). An exploratory investigation into the health and safety aspects of such work was performed to help inform handling practices. Inductively coupled plasma mass spectrometry (ICP-MS) was used on artificial sweat extracts of deteriorated leathers to quantify the elements of concern (As, Pb, Cr, Co, Cu, Cd, Ni, Ba and Se) according to ISO standards. Levels above the permissible limits defined by OEKO-TEX® of As, Cd and Pb were detected in several deaccessioned samples of vegetable-tanned bookbinding leathers from the Natural History Museum, London, some of which had also been dyed or have a pigmented surface finish. The study found that ICP-OES (optical emission spectroscopy) was only sensitive for Cr and Ba and that scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX) was unsuitable for detecting or quantifying the elements of concern. X-ray photoelectron spectroscopy (XPS) could be useful after further experimentation. Based on the results, PPE is recommended for all work where red rot is present and further tests are suggested.