I bet you have all seen water bottles out there that say 'BPA free' on them. If you're like most people, you're not quite sure what BPA is or what it does but having a BPA water bottle is better, right? Wrong, sadly. Last semester, I took a class that amongst other things, focused on endocrine disruptors (basically chemicals that affect hormones) and one of the articles we read was on BPA and BPS.
First, let's start with talking about BPA. BPA, or bisphenol A, is the starting material for making polycarbonate plastics, a type of plastic that is commonly used. Some of this compound is not used in the reaction, which can then leak into the contents of the 'end product', e.g. a water bottle. In the US. there is currently a ban on BPA in baby bottles and sippy cups (apparently that is an actual word) after consumers were concerned of its safety for infants and toddlers. Studies had shown that the chemical mimics estrogen and could harm brain and reproductive development in fetuses, infants, and children. (In my opinion, the FDA should have banned it for all consumer materials, not just those made for infants but hey, I'm not even American.)
Because so many consumers were concerned about having BPA in their products, many companies have chosen to produce 'BPA Free' products, which is most commonly seen on water bottles. Awesome, right? No, unfortunately, the chemical compound that most commonly replaces BPA is BPS (bisphenol S). Sounds very similar, right? That's because it is! Research has shown that BPS has similar effects on the developing brain as BPA. A study conducted by Cheryl Watson at The University of Texans Medical Branch at Galvesorn shows that BPS can disrupt a cell's normal functioning, which could lead to metabolic disorders such as diabetes and obesity, asthma, birth defects or even cancer!! Further, a study by Hong-Sheng Wang, an associate professor at the University of Cinicinnati, found that both BPA and BPS cause heart arrhythmia in rats. Deborah Kurrasch, from the University of Calgary, found that zebra fish fetuses that were exposed to BPS showed a 240% in neuronal growth, which likely lead to hyperactive behavior.
Side note: For those of you who are wondering why I am citing animal studies and how that translates to humans: animal models are the standard for pharmaceutical testing and animals are carefully selected to fit attributes similar to humans. For example, zebra fish have similar brain development than humans but their development is so much easier to track given that they are tiny zebra fish. Findings from animal studies, should certainly be of concern to everyone.
So why should you be worried? While BPS was thought to be less likely to leak, it certainly does and nearly 81 percent of Americans have detectable levels of BPS in their urine, showing that there is certainly an amount of the chemical that enters the body. The problem with all of this is as so often, the lack of regulation of potentially dangerous chemicals in the US. Compounds that have long been banned in the EU, for example, are still used in products in the US. Appallingly, there is allegedly no federal agency that tests the toxicity of new materials before they are allowed on the market. Keep in mind that there are more types of bisphenols out there other than BPA and BPS that could be the next potentially harmful chemical used in your water bottles.
If you want to look for a bisphenol free water bottle, I would suggest buying one out of metal or glass. I have a S'well bottle and while they're quite pricy, they're definitely worth it.
Sources
http://www.scientificamerican.com/article/bpa-free...
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC362118...
http://www.ncbi.nlm.nih.gov/pubmed?term=(Hong-Shen...
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC432123...
