Camphor wood, a potentially harmful museum storage material: an analytical study using instrumental methods.

Camphor wood is welcomed by museums due to its insect-repelling effect but the smell indicates a potential risk to the collections. In order to judge the suitability of camphor wood as a museum storage material, typical camphor wood (Cinnamomum camphora) samples aged for different years were evaluated by conducting the Oddy test. Gas chromatography-mass spectrometry (GC-MS), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and time of flight-secondary ion mass spectrometry (ToF-SIMS) were applied to identifying the volatile organic compounds (VOCs) emitted by the materials and the corrosion products, respectively. The results showed that the camphor wood samples led to visible corrosion on copper and lead coupons. GC-MS indicated that the major VOCs emitted were terpenes and their derivatives, while XRD, EDS, and ToF-SIMS provided various clues to the corrosion mechanisms. Pb(CO)(OH)O and CuO were regarded as the major corrosion products of lead and copper coupons, respectively. The study provides the museum curators and the conservators with abundant information to reassess the application of camphor wood to museums as well as a different way to understand the mechanism of metallic corrosion caused by camphor wood.