The women are referred to frequently as “ghostly” in appearance. This takes on many meanings throughout the book. First, the glow of the radium on their skin and clothes gives the dial-painters a dazzling yet eerie appearance. As they walk home in the dark, observers can see the residue of their work and how stubborn and hard to remove the radium powder is. Second, the nickname of “ghost girls” alludes to an anticipated death. The women are, in a way, already ghosts because their fates are sealed by the radium long before the women begin to feel the effects.

Much like how a ghost is thought to outlast the body of a person and remain undead for a long time, the radium also persists. Radium’s half-life of 1600 years implies that its “ghost” will remain for centuries to come. 

The book’s subtitle, “The Dark Story of America’s Shining Women,” is the most obvious example of this motif. The story is dark—grim, gruesome, and unsettling—while the women shine both metaphorically and literally from the radium paint. In so naming this book, Moore also uplifts the women for their “light”: their sense of justice, persistence, and their individual passions, while emphasizing the injustice and “darkness” of their story.