"A poisonous insecticidal solution has been used in the binding of this book."

"A poisonous insecticidal solution has been used in the binding of this book."

Update:  according to this UNESCO publication from 1961 (“Preservation of Books and Periodicals in Arab Countries” by Wilfred J. Plumbe), that poisonous insecticidal solution is likely a solution of 1% mercuric chloride and  0.5% beechwood creosote applied to the adhesive used on the spine of books before casing in (pg. 6).