First Large Study of Bisphenol A in the American PopulationThis was the first study to look at a large number of adults, test their urine for BPA, and see how this related to major diseases. These subjects would have only the same low-level exposure to BPA that the general population has -- through food and beverage containers and dust. Other studies found effects of BPA in rats and other test animals, but BPA is absorbed and excreted differently in different species. In humans, the BPA taken in from food and beverages is swiftly processed by the liver and excreted in the urine. The test subjects contributed one random urine sample, and had blood tests and a medical history performed to assess their health.
Higher BPA Associated with Higher Incidence of Type II Diabetes and Cardiovascular DiseaseThe study controlled for many factors, including obesity, smoking, age and ethnicity. Higher BPA levels in the urine were associated with a higher risk of diabetes, cardiovascular disease, and liver-enzyme abnormalities. Animal studies have shown that BPA interacts with estrogen receptors and liver and pancreatic cells, which may be the way in which it raises risk for diabetes and liver abnormalities. How it might raise the risk for heart disease isn't known. It is possible that a higher amount of BPA in the urine indicates a person has more exposure to other environmental contaminants as well, and these other contaminants are the real culprits.
How Are You Exposed to BPA?The bad news is that 90% of the US population has detectable levels of BPA, and use of BPA in manufacturing continues to increase. Bisphenol A is used in epoxy resins lining food and beverage containers and as a monomer in polycarbonate plastics, such as clear hard plastic water bottles. People also get continuous exposure through drinking water, dental sealants, and household dust. Where is BPA? Everywhere.
BPA-Free Water Bottles and Baby BottlesWalkers and others who exercise and watch they water intake while dieting often use refillable water bottles rather than disposable ones. Manufacturers of water bottles and baby bottles were swift to reformulate and start making BPA-free water bottles by 2007, once consumers began to be concerned. The only water bottles using BPA in the plastic were clear hard plastic polycarbonate water bottles, with a 7 noted in recycling symbol. If your water bottle is of the clear variety and dates from prior to 2007, it may have plastic that was made using BPA. Bottles made of opaque, softer plastic were always BPA-free. Clear 5-gallon plastic bottles used on water coolers may not be BPA-free. A 7 inside the recycling triangle indicates bottles that may not be BPA-free. Check with your water bottler if you are concerned.
Finding BPA-Free Water Bottles
BPA in Canned FoodsThe food you eat at home, in cafeterias and restaurants may be prepared from canned items, and many cans are lined with a resin containing BPA. This may be an incentive to prepare more meals from fresh whole foods such as fruits, vegetables, and meat from the market. Not only might it reduce BPA exposure, unprocessed ingredients also provides the wider range of nutrients. Unfortunately, it is difficult for the producers of organic canned foods to ensure they are using BPA-free cans because of the way cans are produced and distributed.
BPA in KitchenwareClear, hard plastic is the most likely to be polycarbonate manufactured with BPA. If you can't see through it, you probably don't need to worry about it. Tupperware has a list of the plastic used in all of its items, with polycarbonate used in only a few items. Clear plastic disposable silverware may be made of polycarbonate.
Avoiding BPA in the Kitchen
FDA Considering SafetyThe US Food and Drug Administration was considering the safety of BPA in food containers. A draft report released in August, 2008 concluded that it was still a safe practice. Further studies are needed to make conclusions about the safety of long term low exposure.
Iain A. Lang; Tamara S. Galloway; Alan Scarlett; William E. Henley; Michael Depledge; Robert B. Wallace; David Melzer. "Association of Urinary Bisphenol A Concentration With Medical Disorders and Laboratory Abnormalities in Adults." JAMA. 2008;300(11):1303-1310.