Do you love the musty smell of old books? How about the vinegary smell of degrading plastics? Cultural heritage scientists (as outlined in the video by the American Chemical Society’s Reactions team above) are using their noses to pick apart molecules in ancient artefacts to better understand how the leeching odorous compounds tamper with other museum artefacts.
With technology based on breathalysers that detect blood-alcohol levels, scientists examine the health of rare artefacts – such as old books, film and even early Lego blocks – in a non-invasive way.
In old books, for instance, the distinctive smell is made up of paper molecules cellulose and lignin, as well as degrading inks and rosin, which is used in paper pulp to prevent ink dripping.
As these components break down, hundreds of volatile molecules are released. But the presence of a set of five different molecules (2-ethylhexanol, hexadecane, vanillin, acetic acid and furfural) alert the scientists to the book’s slow, smelly degradation.
And for plastics, acidic molecules (cellulose nitrate and cellulose acetate) waft into the air and can activate other artefacts nearby made of similar substance and set in motion a degrading chain reaction.