BPA and BPS
To BPA or not to BPA...
...in short: NOT. Within the past few years, Bisphenol A (BPA) has become one of the most well known household chemicals in the world. And with good reason.
What is Bisphenol A?
BPA is a synthetic chemical and the primary constituent of polycarbonate plastics and epoxy resins. If you're into the technical chemistry, it is created by condensing acetone and phenol, and is known as 4,4'-dihydroxy-2,2-diphenylpropane; it's chemical structure looks like this:
Several million tons of BPA are produced annually and it is estimated that the global market for BPA is expected to rise to 8.4 million tons by 2018. Production is only increasing to meet this market demand, which is coming primarily from the Asia-Pacific region.
Where is it found?
BPA is literally everywhere, including the air. It is commonly found in baby bottles, water bottles, food and beverage can liners, pacifiers and baby toys, water bottles and large water cooler bottles, cash register receipts, flatware, safety equipment, eyeglasses, dental fillings, computer and cell phone casings, compact discs, DVDs, and epoxy paint and coatings. With the recent controversy, it's presence in some of these products has decreased drastically as it is being replaced by other "BPA-free" plastic resins.
What is especially disturbing is that it is now practically impossible to avoid being exposed to it. In a 2007-2009 study the Canadian Government found that BPA was detected in the urine of 91% of the Canadian population aged 6 to 79 years. Even back in 2003-2004, the U.S. National Health and Nutrition Examination Survey (NHANES III) conducted by the Centers for Disease Control and Prevention (CDC) found detectable levels of BPA in 93% of 2517 urine samples from people six years and older.
Why is it a concern?
BPA is a concern because it readily breaks down and leaches from products made out of it. Plastics and resins made of BPA weaken, and thus leach more BPA when they are old and wearing out, heated or frozen, washed with detergents, and exposed to oily or acidic foods and liquids. Thus, BPA leaching is especially a concern with canned foods, which often are oil-based and/or acidic.
BPA is a hormone or endocrine disuptor, because it mimics hormones, in particular the human estrogen hormones, which are involved in normal cellular function, reproduction, development and behaviour.
Peer-reviewed scientific studies have linked BPA to numerous health problems including chromosome damage in female ovaries, decreased sperm production in males, early onset of puberty, various behavioural changes, altered immune function, sex reversal in frogs, impaired brain and neurological functions, cardiovascular system damage, adult-onset (Type II) diabetes, obesity, resistance to chemotherapy, increased risk of breast cancer, prostate cancer, infertility, and metabolic disorders -- research into the impacts of BPA on human health is extensive and ongoing.
There is now so much research done and being done on BPA, in the Resources section below we direct you to a number of key resources which provide compilations and summaries of the research (including references for research on all the above-listed health effects) and regular updates on BPA issues related to health and the environment
A miniscule amount of BPA may be worse than a lot
"The higher the dose, the greater the effect" is a traditional assumption that emerged hundreds of years ago in the field of toxicology, the study of the adverse effects of chemicals on living organisms. Public health standards have been, and largely continue to be, developed based on the idea that high dose research will adequately predict potential low dose effects of a toxin on health. BPA does not follow this assumption. In fact, it seems to turn this basic toxicological principle on its head.
Solid scientific research with primarily animal studies shows that even very low doses of BPA can have a significant effect on health and can even irreversibly alter fetal development. Low doses of BPA are typically found in the environment or through exposure from BPA-containing materials in everyday life, such as plastics and can liners. One of the leader's in this field is Dr. Frederick Vom Saal, a biology professor at the University of Missouri and specialist in endocrine disruptors such as BPA.
Furthermore, a recent study using human cells has shown that developmental exposure (i.e., fetuses and children) to BPA at low-doses increases the risk of hormone-dervied prostate cancer in humans.
So all the more reason to try and limit your exposure to BPA in any way possible.
Since BPA has been recognized as a problem chemical in consumer products and been banned in certain products in some countries, a profusion of "BPA-free" products made of other plastic resins have entered the market, for example bisphenol S (BPS) or polyether sulfone. And now BPS is beginning to show up in people, possibly through exposure to BPS in thermal paper products such as store receipts.
The fact that a plastic product is made of a non-BPA plastic, does not necessarily mean it is safe. There tend to be few, if any, available research studies on such replacement plastics. And researchers have shown, that some "BPA-free" products actually exhibit more estrogenic activity than plastics containing BPA. It has now been clearly shown that BPS also exhibits hormone-disrupting behaviour that could be even worse than BPA.
We prefer to simply avoid such new products completely because one simply cannot be sure of their safety. And with some of them being chemically to BPA, the possibility of them also exhibiting hormone-disrupting behaviour is significant.
Government of Canada BPA Information
U.S. Government BPA Information
A FEW KEY SCIENTIFIC STUDIES
Rudel R.A., Gray J.M., Engel C.L., Rawsthorne T.W., Dodson R.E., Ackerman J.M., et al. (2001) "Food Packaging and Bisphenol A and Bis(2-Ethylhexyl) Phthalate Exposure: Findings from a Dietary Intervention." Environ Health Perspect. 119(7): 914-920.
Viñas R, Watson CS. (2013) "Bisphenol S Disrupts Estradiol-Induced Nongenomic Signaling in a Rat Pituitary Cell Line: Effects on Cell Functions." Environ Health Perspect 121:352–358.
vom Saal FS, Hughes C. (2005) An extensive new literature concerning low-dose effects of bisphenol A shows the need for a new risk assessment. Environ Health Perspect. 113:926–933.
vom Saal FS, Hughes C. (2006) Bisphenol A: vom Saal and Hughes Respond. Environ Health Perspect. 113:926–933.
vom Saal FS, Cooke PS, Buchanan DL, Palanza P, Thayer KA, Nagel SC, Parmigiani S, Welshons WV. (1998) "A physiologically based approach to the study of bisphenol A and other estrogenic chemicals on the size of reproductive organs, daily sperm production, and behavior." Toxicology & Industrial Health 14(1-2):239-260.
Yang C.Z., Yaniger S.I., Jordan V.C., Klein D.J., Bittner G.D. (2011) "Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved." Environ Health Perspect. 119(7): 989-996.
IMPORTANT NOTES: While we strive to provide as accurate and balanced information as possible on our website, Life Without Plastic cannot guarantee its accuracy or completness because there is always more research to do, and more up-to-date research studies emerging -- and this is especially the case regarding research on the health and environmental effects of plastics. As indicated in our Terms & Conditions, none of the information presented on this website is intended to be professional advice or to constitute a professional service to the individual reader. All matters regarding health require medical supervision, and the information presented on this website is not intended as a substitute for consulting with your physician.
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