When Rose George published The Big Necessity, her study of global sanitation and toilet access, the natural comparison was to Mary Roach, who is known for her nonfiction treatments of earthy and scatalogical topics.

But George, while still bringing a sense of humor to her work, isn’t a humorist. The Big Necessity featured the occasional laugh, but it was by no means toilet humor. It was just a book about how important sanitation and bathrooms are to contemporary societies, and their impact on health both public and private.

Her new book, 90 Percent of Everything covers maritime shipping, those giant boats carrying hundreds or thousands of intermodal shipping containers.

She goes on board a Maersk boat as a supernumary to understand the misery and boredom of shipboard life, joins a Portuguese naval vessel off the Somali shore to talk piracy, visits a whale-research vessel to talk pollution. All the while she recounts the horrifying underpayment and mistreatment of merchant sailors, and the ways the multinational freight companies manage to fly flags of convenience and escape even the most basic responsibility for the lives of their crews and the oceans they float on.

It’s a revealing look at an industry we just don’t think about that much, even though, as she points out, about 90 percent of everything we consume has at some point been on a ship.