Library copies of the bestseller 'Fifty Shades of Grey' were found to carry traces of herpes virus and cocaine.
The scientists from the Catholic University of Leuven in Belgium tested the ten most frequently borrowed books on the shelf, the Daily Express reported.
Another romance, Tango, written by Pieter Asper, was also found to be carrying herpes, while all the ten books were tested positive for cocaine.
Jan Tytgat, a professor of toxicology, said the residue on the books was too small to be considered seriously harmful and the consciousness or behaviour of the reader won't change as a result of reading it.
According to previous studies, the highly sought after library books have 25 to 40 percent more microbes on them than less borrowed ones.
The 'Fifty Shades of Grey' movie, adapted from the EL James novel, will be released in February 2015 and is directed by Sam Taylor-Johnson.