Why do it? Because science.
(Quite possibly my favorite picture ever of Herbert West, you should check out the original artist here)
Of course one of the most popular books was Fifty Shades of Grey because hey- sex is popular, especially when you can get it in a format that's socially acceptable.
What did they find? All of the books tested positive for enough cocaine to potentially have someone test positive on a drug test. However FSoG had that little something extra:
Yep. These books had herpes on them. Not enough to where you could actually contract it, but enough to where it showed up. It's entirely possible that the herpes on them were of the cold sore variety. Not every person with herpes has it below the waist, after all, and it's entirely reasonable to think that someone could have been touching their face and passing herpes on.
(Like this, actually)
Of course it's far more funny to think that it's the result of someone trying to do the kitkat shuffle while reading their library rented erotica. Gross, but funny. Next time I check a book out from the library, it might go through this process:
*Professors Test Fifty Shades of Grey Library Book, Find It Has Traces of Herpes