What is Bisphenol A?
FACT SHEET ON BISPHENOL A - Cancer Association of South Africa (CANSA)
August 2010
Compiled by Dr C Albrecht – Head of Research
- Bisphenol A (abbreviated BPA) is a high-production volume, artificial, industrial, manmade molecule that was first synthesised in 1891 by A.P. Dianin.1 It is an ever-present environmental contaminant with established endocrine disruptor properties
- It is a relatively small symmetric, organic compound (see below) with a molecular weight of 228. It is a white powder and surprisingly has been found to mimic the female hormone, oestrogen, by binding to the oestrogen receptor. It is one of the best examples of a so-called endocrine-disrupting compound (EDC) because it binds to oestrogenreceptors in the cell in a haphazard, uncoordinated way - disrupting the highly ordered working of the normal hormone, oestrogen, especially during pregnancy, and causing various health defects, i.e. it is a pseudo-oestrogen
- BPA was investigated in the 1930’s as a possible synthetic oestrogen to be used for miscarriages. However, it was not developed further because another synthesized compound, diethylstilbestrol (DES), was found in 1940, which turned out to be a much more powerful oestrogen substitute in humans than BPA. Contrary to expectations DES was later taken off the market in 1970 when it was found to be linked to vaginal adenocarcinoma (cancer) and foetal malformations in daughters of 7 million mothers who used the drug while pregnant. This was a pharmaceutical disaster and in retrospect was an early warning signal for similar toxic properties confirmed for BPA 30 – 40 years later.
WHY IS BISPHENOL-A A MATTER OF CONCERN?
- Exposure to BPA has been linked to increased breast cancer risk, early puberty, obesity, infertility in males and females, brain dysfunction, thyroid dysfunction, heart disease, diabetes and prostate cancer
- Evidence has been found that BPA acts epigenetically, at low concentrations, to permanently silence critical genes during development in the womb with as yet unknown consequences
- Substantial evidence indicates that exposure to BPA during early development may increase breast cancer risk. This is supported by studies showing that BPA activates genes involved in growth in mammary cells
- Children may be particularly vulnerable to BPA
- BPA was detected in the urine of 92% of the U.S. population in 2003-2004 and it is most likely to be in an average South African’s urine as well
- BPA is not essential and provides no known benefit to human health and appears to be harmful to human health
- In 2007 Prof Fred vom Saal of the University of Missouri-Columbia (World expert on BPA) found that very low level exposure of BPA ( 1 nM) harms the prostate
- Between 1997 and 2008, over 100 publications linked very low level exposure of BPA with prostate damage, breast and prostate cells predisposed to cancer, decline in testosterone, changes in breast tissue that predispose cells to hormones and
carcinogens, early puberty, behavioural problems and other effects
• These effects have been found at BPA concentrations up to 25 times lower than the U.S. Environmental Protection Agency’s (EPA) “safe” dose of 50 micrograms per kilogram (body weight) per day22,23
- 38 Independent BPA scientists (Chapel Hill Panel) completed an assessment of BPA
safety in 2007 and concluded that BPA exposure at current levels presents a clear risk to human health24
- In a New York Times editorial (May 20th 2008), a ban on BPA in the U.S. is called for in terms of items such as baby bottles and cups
- BPA induces a profile of tumour aggressiveness in high-risk cells from breast cancer patients
- Prenatal exposure to BPA induces early cancerous changes in the breast tissue of rats
Please download and read the full fact sheet - knowing about Bisphenol A and how to avoid this chemical could literally save your life!
Submitted by storytelling on 10 December 2010 - 8:20am. categories [ ]
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