A fascinating post, Alex.
Yes, the good old bright green pigment known as copper arsenate….. The Victorians were fond of it, and used it even for colouring sweets. Mind you, they probably had more arsenic in their bodies from other sources. There is a famous story about this pigment, also called Paris Green, where it was used in wallpapers. In damp conditions fungal growth on wallpaper breaks down the pigment to the very toxic gas arsine, or arsenic trihydride. Now that is very toxic indeed. In confinement on the prison island of Elba, Napoleon was once thought to have been poisoned by the decomposition of his somewhat damp green wallpaper, which was shown to contain Paris Green, but I think the verdict was that his death was due to other factors. Of course there were many sources of poisonous compounds. White paint was then lead sulfate, and Cadmium yellow was a very toxic and popular pigment for artists. Not to mention medicines like calomel (Mercury chloride). Take your pick!
In summary I would not get too excited about green coloured Victorian books, unless you have a big pile of mouldy damp ones. The Victorians certainly knew how to poison themselves.