A warning has been issued by scientists over old books which contain toxic substances.
Books dating back more than 100 years have been found to have poisonous dyes.
They include lead and chromium up to six times above acceptable legal levels, according to new research.
People have been urged to ‘handle with care’ or even steer clear altogether of any brightly coloured, cloth-bound books from the Victorian era.
Dyes that create the bold covers could pose health risks to readers, collectors and librarians, scientists say.
An array of books have now been removed from library shelves while others dating back to the 19th century which are yet to be tested have been sealed in plastic zip-close bags for handling and storage.
‘These old books with toxic dyes may be in universities, public libraries and private collections,’ said research co-author Abigail Hoermann, from Lipscomb University in Nashville.
‘Users can be put at risk if pigments from the cloth covers rub onto their hands or become airborne and are inhaled.
‘So, we want to find a way to make it easy for everyone to be able to find what their exposure is to these books, and how to safely store them.’
Chemistry undergraduate Ms Hoermann carried out the tests with assistant chemistry professor Dr Joseph Weinstein-Webb, fellow student Leila Ais and recent graduate Jafer Aljorani.
The team used three techniques – including one that hasn’t previously been applied to books – to assess dangerous dyes in the university’s book collection and found some volumes may be unsafe to handle.
Metal concentrations in some of the book covers were found to be above acceptable legal limits for chronic exposure.
In the dissolved sample from the most contaminated cover, the lead concentration was more than twice the Centres for Disease Control and Prevention (CDC) limit, while the chromium concentration was almost six times over.
Chronic exposure to inhaled lead or chromium can lead to health issues including cancer, lung damage or fertility issues.
Dr Weinstein-Webb said: ‘I find it fascinating to know what previous generations thought was safe, and then we learn, oh, actually, that might not have been a great idea to use these brilliant dyes.’
Books confirmed to contain dangerous dyes were also sealed in bags and removed from public circulation.
Ms Hoermann added: ‘Moving forward, we want libraries to be able to test their collections without destroying them.’
The researchers presented their findings at a meeting of the American Chemical Society (ACS) in Denver, Colorado.
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