Aberdeen University has made irreversible renovations to its historic 500 year-old chapel that academics fear will damage its unique medieval choir stalls.
King's College Chapel celebrated the quincentenary of its foundation last weekend. But staff have been dismayed to find that during maintenance work, the choir stalls have been treated with linseed oil, which they believe could lead to the wood drying out and cracking.
A university spokeswoman said: "Linseed oil is commonly used to treat timbers in historic buildings and has been used successfully in King's Chapel for many years."
But while the chapel contains a range of historic woodwork, academics are unaware of the choir stalls having been treated before. Derek Sinclair, technical director of the Scottish institute of wood technology at the University of Abertay, Dundee, said that while linseed oil could be used on external historic timbers to protect against water penetration, it made the wood more brittle.
"If it has sat without treatment for 500 years and hasn't fallen apart, I wouldn't advise going in and doing anything," he said.
Polyethylene glycol would have given a similar effect to linseed oil, but can be washed off, while linseed oil seeps in, he said.