Non-invasive monitoring of oil paintings’ degradation via volatile emissions

Oil paints are characterised by complex chemical curing, ageing and degradation processes. These can lead to challenging conservation issues such as delamination of the paint or formation of disfiguring new components. The chemistry behind these phenomena is an ongoing research topic. Nevertheless, effectively addressing the conservation issues requires a quick and confident method to assess the degradation status of the painting. For this purpose, innovative emission collection methods are very promising to non-invasively investigate the composition and thereby the conservation state of artworks. Emission analysis can detect the volatile compounds emitted by the painting. The goal of the PaintWatch action will be to correlate volatile emissions from oil paintings with their health state. This will be done by developing a protocol for the study of volatile emissions, based on a fully non-invasive sampling strategy coupled with gas chromatography-mass spectrometry analysis. This method will have no impact on the integrity of the artwork, thus allowing frequent analysis and monitoring of ongoing damage processes. This goal will be achieved by the systematic study of emissions from oil paint mock-ups, naturally and artificially aged, and validation with the results from historical oil paintings. Statistical and multivariate data analysis methods will be used to identify significant trends, and all the results will be published in an online open-access database.PaintWatch will be the first step in the use of headspace analysis for the conservation of oil paintings. In the future, the developed protocol will have the potential to be further adapted to study the condition of other complex and multi-layered materials, in the cultural heritage field and beyond.