(Web Desk) - From The Bible to The Satanic Verses, several books were banned in parts of the world at various points in time due to the perception that they poison minds.
But some books can be poisonous quite literally, as the chemicals used in their making are harmful to humans.
According to a study done by a team of researchers at Lipscomb University in the US, some of the bright-coloured, cloth-bound books from the Victorian era onwards might contain such chemicals.
These colours come from dyes that might be a health risk to readers, collectors or librarians, said a release on the study.
Chronic exposure to inhaled lead or chromium could lead to even cancer, lung damage or fertility issues, said the researchers.
Pigments from the cloth covers can be harmful if rubbed onto hands or become airborne and are inhaled, they added.
“These old books with toxic dyes may be in universities, public libraries and private collections,” Abigail Hoermann, a chemistry student at Lipscomb University, who was part of the study, was quoted as saying in the study.
“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,” the release quoted Joseph Weinstein-Webb, an assistant chemistry professor at Lipscomb, who did the study along with his students, as saying.
The study examined some 19th- and early 20th-century fabric-covered books from the university’s Beaman Library.
The poisons were detected using three spectroscopic techniques: XRF or X-ray fluorescence spectroscopy, ICP-OES or Inductively coupled plasma optical emission spectroscopy, and XRD or X-ray diffraction technology.
XRF was used for checking arsenic or other heavy metals on the book covers. ICP-OES examined the concentration of those metals. XRD was used to identify the pigment molecules that contain those metals.
Researchers found lead and chromium present in some of the Lipscomb books.
In some instances, these heavy metals were in the form of lead (II) chromate, a compound that was used for the chrome yellow pigment by Vincent van Gogh in his sunflower paintings, said the release.
In some cases, metal concentrations were found to be above acceptable limits for chronic exposure as set by the Centers for Disease Control and Prevention (CDC). The lead was more than double the CDC limits, and chromium almost six times the cap.
Such poisonous and potentially harmful books were sealed in plastic bags for handling and storage or removed from public circulation.
Earlier, the Winterthur Museum, Garden & Library in Delaware found copper acetoarsenite, an arsenic compound, in some 19th-century books in its collection.
This emerald-green pigment was used in Victorian-era wallpaper, garments and cloth book covers.
This discovery led to the launch of the 'Poison Book Project', a crowdsourced research effort. The project uses various imaging and chemical processing techniques to trace the toxic pigments in books around the world.
The researchers at Lipscomb University hope to contribute their findings to the Poison Book Project.