The breast milk of the writer Florence Williams contains a striking level of perchlorate, a key component of rocket fuel. This does not, however, invest her with superpowers, as it might if she were a comic-book hero, or even make her special. Rather, as she explains in “Breasts: A Natural and Unnatural History,” her mammary glands are no different from those of most American women. In the year 2012, breast-feeding still passes many good things from mother to baby: vitamins, minerals and “a solid hedge of extras to help ward off a lifetime of diseases.” But the practice also typically transfers “paint thinners, dry-cleaning fluids, wood preservatives, toilet deodorizers, cosmetic additives, gasoline by-products, rocket fuel, termite poisons, fungicides” and varieties of flame retardants, one of which, Penta-BDE, was banned by the European Union because of its chronic toxicity to humans.

“Breasts” is less a primer on anatomy than a catalog of environmental devastation akin to Rachel Carson’s 1962 classic “Silent Spring,” which detailed the impact of industrial chemicals — notably, the pesticide DDT — on animal life. But Williams, who cites Carson as an inspiration, has written a far scarier book. Carson examined birds and fish. Williams looks at us.

Breasts are made of fatty tissues that absorb “pollutants like a pair of soft sponges,” she writes. They are malignancies waiting to happen. The incidence of breast cancer worldwide has doubled since 1940, and continues to rise. Because of various factors, which might include obesity and industrial contaminants, breasts are arriving earlier and becoming larger, often to the point of grotesqueness. Brassiere manufacturers who once made cups in sizes A to D have had to extend their range to H and KK.

For generations, male thinkers and opinion-shapers from Sigmund Freud to Hugh Hefner have enshrined the female breast as a locus of eroticism and nurturance. In “Breasts,” Williams upends that perspective. She shows us our breasts as museums of deadly detritus — monstrous, menacing, potentially lethal. Breasts, the columnist Dave Barry once said, exist “to make males stupid.” Today, when used for nursing, they could be making our children stupid: “Toxins in breast milk have been associated with lower I.Q., compromised immunity, behavioral problems and cancer.”