From Scientific American:
A new study indicates that bisphenol A (BPA), a chemical used in plastic bottles and can linings that has been linked to heart disease, diabetes and liver failure, may linger in the body far longer than previously believed. Environmental health scientist Richard Stahlhut of the University of Rochester Medical Center and his colleagues discovered that even those who had been fasting for 24 hours still had high BPA levels in their urine, using a U.S. Centers for Disease Control and Prevention (CDC) survey of 1,469 adults.
Stahlhut says that it appears that the amount of BPA in the body drops relatively rapidly from four to nine hours after exposure, but then levels out. “After the nine hours or so,” he says, “it stops doing what it's supposed to and the decline goes flat.” Previous research had suggested that levels of BPA, which mimics the female hormone estrogen in the human body, declined by 50 percent every five hours after it was ingested in foods or water it had leached into from plastic containers. But the new research indicates that the chemical declines initially but then sticks around, making it potentially more harmful.
More here.