A new study has found higher than expected levels of a controversial plastics chemical in people who had fasted for 24 hours. This surprised researchers because the chemical, bisphenol A (BPA), was thought to be ingested when trace amounts leaked from plastic food containers and bottles, and researchers thought it quickly passed through the system.
The finding suggests that exposure to BPA may come from many different sources, not just food products, or that the body doesn't metabolize the chemical as fast as has been thought, the researchers said.... "What this study shows is that either we are getting exposed to a lot more BPA than we thought, or it's hanging around longer than we thought, or both," said lead researcher Dr. Richard W. Stahlhut [HealthDay News].
The plastic-hardening chemical BPA is most commonly associated with reusable water bottles and baby bottles, but Stahlhut notes that it turns up in many other surprising places, including
PVC water pipes and food-storage containers. It's also used to coat the inside of metal food cans and in dental sealants. It's even found in cash register receipts and recycled paper, he said [HealthDay News].
In the study, published in Environmental Health Perspectives, researchers examined data from a government nutrition study involving 1,469 adults. They looked at the amount of BPA in the urine and the length of time the participants had been fasting before the sample was taken. Stahlhut was surprised to find 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" [Scientific American].
It may be, he says, that people are getting BPA from water flowing through plastic pipes, or else that the chemical is accumulating in people's bodies, possibly in fat tissue. The debate over whether BPA poses a heath risk has been fierce, and government agencies have issued conflicting reports.
U.S. government toxicologists at the National Institutes of Health last year expressed concern that BPA may have harmful effects on the development of the prostate and brain and induce behavioral changes in fetuses, infants and children. A 2008 study by British researchers showed that high levels of BPA in the body were linked to heart disease, diabetes and liver-enzyme abnormalities [Reuters].
But the Food and Drug Administration has maintained that the amount of BPA that leaches out of plastics is too small to pose a threat. Related Content: 80beats: More Bad News on BPA: Linked to Heart Disease and Diabetes in Humans 80beats: Controversial Plastics Chemical Causes Problems in Monkey Brains 80beats: FDA Declares Chemical in Baby Bottles Safe, but Doubts RemainImage: iStockphoto