It’s hard to be boobs. Sure, breasts are cherished as givers of milk and the pinnacle of sex appeal, but the modern world hasn’t been good to mammaries.

As Florence Williams writes in “Breasts: A Natural and Unnatural History,” they’re the most tumor-prone organ in the human body. They “soak up pollution like a pair of soft sponges,” and transmit environmental toxins to babies through breast milk. “Breasts are bellwethers for the changing health of people,” she says. While we’ve “genetically modified our crops to be able to protect them from the ill effects of pesticides,” Williams writes, “we haven’t yet figured out how to modify our breasts.” Aside from using saline and silicone, of course.