Inspired by Morgan Spurlock’s fast-food gluttony in the movie Super Size Me, two environmental activists from Canada devised their own experiment. Instead of fast food, Rick Smith and Bruce Lourie absorbed themselves in everyday products like shampoos, soaps and cleaners to find out what kind of damage might be done to their health.

Their book about the adventure is called Slow Death by Rubber Duck: The Secret Danger of Everyday Things. Smith tells Guy Raz that writing the book was like conducting an adult science fair project – with one cardinal rule.

“Our experiments had to mimic everyday life,” Smith says. “Obviously it would be very easy to dramatically increase your Teflon levels if you were willing to drink some Teflon, but nobody does that, so it wouldn’t have any applicability to daily life.”

But Smith and Lourie didn’t need to take baths in mercury or eat tuna for a whole year to see the chemical levels in their bodies skyrocket. After just two days of eating only canned food microwaved in plastic containers and drinking from one of his son’s old baby bottles, Smith saw a major rise in the levels of BPA in his body.

“My levels increased over eight times,” he says. “You can only imagine what the levels in an infant would look like if after two or three years of their sole source of nutrition being a BPA baby bottle. Their levels would just be through the roof.”

Smith says children are especially vulnerable to chemicals such as BPA.

“As the bodies of children are developing, their cells are dividing. Their brains and their organs are growing. All of these processes in childhood and development are hormonally driven, and so the introduction of even a very small amount of a hormonally active chemical into the body of a child can have very large effects, disproportionate to the actual amount of chemical we’re talking about,” he says.