Narrator: This is Science Today. Ninety-five percent of the U.S. population has detectable levels in their system of bisphenol-A, or BPA. The estrogen-like compound has been used for decades in a large number of products from canned foods to hard plastic bottles. Yet research epidemiologist Jonathan Chevrier of the University of California, Berkeley, explains that for a long time, no one seemed very concerned about it.
Chevrier: It's relatively recent that people are concerned about any kind of chemical leaching out of plastic into their food. It's interesting how it happened — a scientist was doing tests in culture cells and then realized that the cells that were really sensitive to estrogen kept developing on their own without adding any estrogen. He thought there was some problem with the culture that he was getting. Until after several tests he realized it was the Petri dishes that he was using that was leaking an estrogen chemical and that was identified as being BPA.
Narrator: Chevrier's group recently linked BPA to changes in thyroid hormone in pregnant women and newborn boys. Their preliminary findings have added to mounting concerns about BPA. For Science Today, I'm Larissa Branin.