Pity the poor librarians. Those gentle custodians of the written word currently find themselves in a regulatory purgatory of sorts wherein compliance with hellish safety standards threatens to defy their hallowed purpose of providing books for all.

It is a dilemma borne of the Consumer Product Safety Improvement Act of 2008, which prohibits even minute levels of lead in any product intended primarily for children 12 years of age or younger. That includes millions of children’s books printed with leaded ink. (Use of the metal in ink dates back centuries—including publication of the Gutenberg New Testament.)

Although lead in ink was phased out in the late 1970s, there’s no date certain when it was abandoned altogether. Consequently, the Consumer Products Safety Commission (CPSC) deems any children’s book printed prior to 1986 to be potentially toxic and thus unfit for library circulation, the Goodwill store, or your neighbor’s garage sale.

According to the CPSC: “[T]he Commission has tested older books and found books printed in the 1970s and earlier that exceed the lead limits. The retroactive applicability of the lead limits creates problems for libraries and used book stores because some older books were printed with inks containing lead in excess of the new lead content limits.”

However, the actual risk of lead exposure from older books ranks only about 0.5 on a scale of one to 10, according to the Centers for Disease Control and Prevention. Nonetheless, the CPSC has urged libraries to put older children’s books in storage until they can be tested for lead toxicity—at a cost of $300 to $500 each.