An international research team has devised a smell test that determines exactly how degraded the compounds in an old book are, and how best to counteract the decay without having to damage the book to take samples. The method is felicitously named “material degradomics”.
Lead researcher Dr. Matija Strlic from University College London’s Centre for Sustainable Heritage noticed that conservators often smelled the books to assess conservation needs. That gave her the idea for creating a smell test that would pinpoint the volatile compounds that are released as the paper ages and degrades.
The test employs gas chromatography-mass spectrometry to analyze the paper, binding, etc. and separate out the different compounds.
The team tested 72 historical papers from the 19th and 20th centuries – some of which they bought on eBay – and identified 15 compounds that were “reliable markers” of degradation.
“The aroma is made up of hundreds of compounds, but these 15 contain most of the information that we need,” said Dr Strlic.
Measuring the levels of these individual compounds made it possible to produce a “fingerprint” of each document’s condition.
Once they have that fingerprint, librarians and conservators can more accurately determine which books are in greatest danger of degradation. Knowing which compound is at what level will also help fine-tune the conservation process.
The system isn’t quite ready for primetime. Gas chromatography-mass spectrometry devices are still rather unwieldy and they use samples. Dr. Strlic is working on making a portable “material degradomics” machine which could easily be deployed by librarians to find out all kinds of things about a book, not just the compounds degrading on the pages, but also its age and what materials were used to make it.