Camphor Wood Used as a Museum Storage Material: An Indoor Air Pollution Source Harming Metallic Objects

Camphor wood is welcomed by many museums for its insect-repelling effect, yet the smell indicates a potential risk to the collections. In order to judge the suitability of camphor wood as a museum storage material, camphor wood samples of different ages were evaluated by using the Oddy test. Gas chromatography-mass spectrometry (GC-MS) and X-ray diffraction (XRD) were applied to identify 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. Pb₁₀(CO₃)₆(OH)₆O was identified as the corrosion product of lead coupons. The study provides 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.