BPA: Worse than we thought
Human exposure to the chemical bisphenol A (BPA) is higher than previously known, and a number of its sources remain unknown. That’s according to a new study published in Environmental Health Perspective online journal.
Researchers at the University of Missouri-Columbia, including Frederick vom Saal (see “The myth of the BPA-free diet,” Feature story, Dec. 3, 2009), University of California-Davis and Washington State University measured BPA levels in adult female rhesus monkeys and mice and compared their findings with previously published data on BPA in women. Their conclusion: “Total daily human exposure is via multiple routes and much higher than previously assumed.”
For instance, known sources of BPA include hard plastic baby and water bottles (particularly those labeled with the recycling number 7), the linings of canned food and drinks, medical equipment, some dental sealants and, more recently discovered, thermal (carbonless) paper receipts. The study also names children’s books and cigarette filters as other newly discovered sources of BPA.
BPA is an endocrine disruptor to which, according to the Centers for Disease Control, more than 90 percent of U.S. citizens are chronically exposed. It’s linked to developmental and reproductive disorders, obesity, heart disease, diabetes and other health issues. The Food and Drug Administration said in January it has “some concerns” about the chemical, but it is still considered safe by regulatory agencies, something some scientists and health advocates are trying to change.
The study said that, while much remains to be known about how BPA works in the body, “understanding the current levels of human exposure and the various routes of exposure to BPA, how BPA is metabolized, and whether animal models are relevant for modeling human exposure is critical to better understanding the risk posed to humans.”