Bisphenol A, or BPA as it is more commonly known, has been a cause for concern for some years now. BPA is a known endocrine disruptor that upsets the body's hormonal systems and has been linked to chronic health conditions such as asthma, diabetes, and ovarian dysfunction. It is found in many everyday items including the paper till rolls used for cash register receipts, the lining of food and beverage cans, as well as in plastic beverage bottles, and until recently was also used in the manufacture of baby bottles and sippy cups before the FDA banned this in 2012. It is also found in more than 92% of American adults and children over the age of six.

Because of the ubiquitous nature of BPA in the environment, researchers began to wonder what impact this chemical might be having on our drinking water, which may become contaminated at the supply source by discarded plastic debris or if the chemical leaches into the water as it flows through PVC water pipes when it is pumped through the water distribution network.

The majority of public water suppliers treat water with chlorine to kill harmful bacteria and make it safe to drink. However, the chlorine also attaches to BPA, which effectively becomes 'chlorinated', leading scientists to ponder what effect this chlorinated BPA could have on the human body.

After conducting numerous cell-culture experiments, researchers from the University of Texas Medical Branch at Galveston found that these modified forms of BPA produced new, but no less disturbing, effects. “We found that when you modify the BPA it works just as dramatically but in different ways on the same systems,” said professor Cheryl Watson, senior author of the study that was recently published online in Endocrine Disruptors.

Watson, together with student René Viñas, analyzed chlorinated BPA as well as BPA that had experienced sulfonation and glucuronodation – both processes that the human body utilizes to render compounds easier to excrete. According to the study, “in all three cases the modified forms of BPA worked through membrane estrogen receptors to deactivate key signaling enzymes known as ERK and JNK kinases.”

“These kinases are major control centers, gathering all the cell signals, making decisions and then expediting them,” explains Watson. “If you change the dynamic by inactivating kinases, you can mess up cell signaling.”

Results were observed at very low concentrations of BPA, which is a common phenomenon with membrane receptors, but varied erratically as concentrations were adjusted.

While it may be difficult to completely prevent exposure to BPA, you can certainly takes steps to reduce your risk of exposure. As BPA is more likely to leach into water or other beverages when it stands for long periods of time, it is best to avoid bottled water or other beverages sold in plastic bottles that are likely to have been stored on the shelf for some time. While some water filters are not able to remove BPA, they can remove chlorine to prevent potential chemical reactions from occurring should water come in contact with BPA in plastic drinking bottles or sport water bottles after it leaves your tap.

Journal Reference:

René Viñas, Randall M. Goldblum, Cheryl S. Watson. Rapid estrogenic signaling activities of the modified (chlorinated, sulfonated, and glucuronidated) endocrine disruptor bisphenol A. Endocrine Disruptors, 2013