Digitized silhouette portraits shed light on 19th century life (nytimes.com)

> It’s unclear how the arsenic ended up on the book’s pages, but it was considered safe in small doses in the 19th century, and was often found in food, medicine and even common goods like face powder. An arsenic-based green pigment was used in wallpaper in Britain at the time.

I’ve loved very old books since childhood. But it had never crossed my mind that they could contain physical (chemical) danger.

Let’s just hope that the book in the article is a real statistical outlier.