BPA, bisphenol-A(BPA), is a plasticizer, a chemical added to plastic to make it softer, clear and more resistant to shattering. The problem is that bisphenol-A is just one of the chemicals added to plastic that has the ability to stimulate estrogen receptors. What this means is that our cells will react to these chemicals as if they are under the stimulation of estrogen. We worry about hormone sensitive cancers when we think of Bisphenol-A and other estrogen-like chemicals but there are also studies on animals suggesting an increased risk of heart disease. Furthermore elevated levels of Bisphenol-A in the urine of children and adolescents has been linked to a significant increase in rates of obesity. http://www.ncbi.nlm.nih.gov/pubmed/22990270.
Manufacturers have come up with ways to eliminate BPA from some plastics, however the results are misleading in that most of these new plastics are not confirmed to be safe either. Just because it says BPA-free it does not mean that the product is free of other chemicals which mimic estrogen in our body. Tritan is a plastic manufactured by Eastman. It is used in the following products according to:
Camel BakEddy Kid's BPA-free water bottle
Camel BakRelay water filteringpitcher
Foogoby Thermos sippy cups
Hamilton Beach Multi-Blend blender
Nalgene BPA-free water bottles (color matters; see the chart below)
OXO Good Grips LockTop food-storage containers
RubbermaidHydration Chug bottles
Rubbermaid Premier food-storage containers
Thermos Under Armour water bottles
Weil Baby bottles
Weil Baby sippy cups
Whole Foods bulk bins
Eastman claims that its plastic, Tritan, is safe. George Bittner a neurobiologist with a lab in Austin, Texas who now is a founder of PlastiPure has disputed the claims by Eastman. He claims that Estman did not disclose that Triphenyl phosphate (TPP) was found in Tritan plastics and furthrmore that it is estrogenic despite the fact that it is BPA-free. Now the credibility of the study http://www.ncbi.nlm.nih.gov/pubmed/25477047 that called into question Tritan's safety is itself being questioned, as Estman won a lawsuit against Mr. Bittner and his lab. Furthermore, George Bittner's motives are being questioned since he is now working for PlastiPure who is said to have created a plastic that is completely free of estrogenic activity (EA). I have contacted PlastiPure and they could not provide me with a date when their plastic prooducts would become available.
Because of the technical aspects of evaluating plastics and their potiential for harm, you really have to be an expert to decipher the results of these studies and evaluate the study design and methodology used. Because of this it is extremely hard to come to a solid conclusion regarding safety/toxicity studies.
I personally think it is fair to say that BPA-Free can not be guaranteed to be safe. There are too many chemicals used to make these plastics whose safety has not been confirmed. I personally think that using stainless steel bottles is the safest, just make sure they are not lined with any plastic. If you are looking for baby bottles and sippy cups again stainless steel in combination with a food grade silicone nipple or straw.
The following website provides a detailed review of alternatives to plastic sippy cups and also offers the follwing explantion about the leaching of metals from stainless steel which should be minimized providing you are not storing hot or acid liquids in these containers.
Does stainless steel leach?
Yes. A teensy amount of nickel and chromium (or at least cookware does when heated or scratched or both). While this is not likely a health issue so long as you do not have a nickel allergy, it’s not a great idea to store hot or warm items, or highly acidic items, in stainless steel. (This applies to cookware as well, obviously.)
Thank you for reading my first entry!
--Dr. Ian Moore
San Diego, CA