Archaeological wood from the Wieliczka Salt Mine Museum, Poland - Chemical analysis of wood degradation by Py(HMDS)-GC/MS

A combination of analytical pyrolysis with gas chromatography and mass spectrometry (Py-GC/MS) was used to study the chemical composition and level of decay of wood objects from the historical site of the Wieliczka salt mine (Poland). The site has been on UNESCO's First World List of Cultural and Natural Heritage since 1978. The wood is located underground in the form of structures supporting the roofs and walls, as well as machines and mining equipment. It has been gradually saturated with rock salt (sodium chloride) over tens and hundreds of years. The presence of numerous metallic connections has significantly contributed to the destruction of the wood artifacts. Iron under conditions of high salinity is subjected to processes of electrochemical corrosion and produces compounds that penetrate wood, accelerating its degradation. The results have been interpreted with the support of principal component analysis (PCA). The chemometric evaluation of the Py-GC/MS data contributed to an understanding of the chemical differences and similarities between the samples.