Bisphenol A (BPA) increases Prostate Cancer Risk – new study

By Dr. Geo

Doggy Bag Message First·      

• Boy fetuses exposed to BPA by their mothers may develop prostate cancer later on in life.
• BPA has shown to cause male infertility in mice and in humans
• All men (and women) should limit exposure to BPA when possible. BPA is unbiquitous
• BPA is found in plastics, inner lining of food cans,  receipts and paper money

What’s BPA?
Bisphenol A (BPA) is a xenoestrogen (synthetic estrogen) like chemical used to make primarily plastic products. Xenoestrogens mimics the action of the female hormone estrogen. BPA is used to make polycarbonate plastics and is found in in some paper receipts, paper money and inner lining of some canned foods.

Details of the Study
Study researchers from the University of Illinois took prostate cells of young-adult deceased males and implanted these prostate cells inot male mice. The mice were then fed material with BPA in amounts similar to what a fetus would be exposed to for two weeks. After one month, the mice were given estrogen to match the naturally rising estrogen that occurs in aging men. Prostate tissue was collected after two to four months and analyzed for prostate disease. One third of the tissue samples in tissue exposed to BPA found that a third of tissue samples had either pre-cancerous lesions or prostate cancer, compared to only 12 percent of the group of mice fed only oil. (Prins et al. 2014)

My Take On This
This new study adds to a body of research that suggests exposure to low doses of BPA leads to health problems later in life including prostate cancer and male infertility.
In one study of 427 male workers in regions where high levels of BPA exposure existed revealed that increase urine BPA level was associated with worsening male sexual function. The study authors concluded, “Our results reveal a correlation between a biological measure of urine BPA level and declining male sexual function. This finding may enhance the understanding of the BPA effect in human populations, and may have important public health implications given the widespread human exposure to BPA.”( Li et al. 2010)
In animal models, estrogens can drive carcinogenesis of the prostate and have long been suspected of playing a role in human prostate cancer. Scientists have hypothesized that prenatal exposure to estrogen-like compounds, including BPA, may account for recent increases in rates of prostate cancer. A rat study at the University of Illinois at Chicago Department of Urology provides the first evidence of a direct link between low-dose BPA exposure during development and later prostate cancer (Ho et al. 2006).
In the study groups of newborn rats were given high or low doses of estradiol or an environmentally relevant dose of BPA. One key prostate gene that normally fuels cell growth during development stayed turned on in the prostates of male rats exposed to BPA or elevated estradiol from birth. (Ho al. 2006)

What to do
Although making extrapolations from animal studies can be a stretch at times, the research regarding male infertility and prostate cancer in mounting and compelling. At this point it makes sense to reduce the exposure of BPA as much as possible. Of course, this can be difficult considering that products exposed to plastics are everywhere. It’s not impossible though.
7 Tips to Reduce BPA exposure:
1. Reduce the use of can foods. Look for products that are in BPA-free containers. If it doesn’t say is BPA-free, assume it has it.
2.Choose glass bottles instead of plastic for water, juices or any products typically found in plastics.
3. Most plastic products are marked with a number, known as the recycling code surrounded by circling arrows that corresponds to the type of plastic it is made of. Read the number on the bottom of plastic bottles and avoid numbers 3, 6 and ESPECIALLY # 7 plastics. All plastics marked #7 contain BPA. In 2011 researchers looked at 455 common plastic products and found that 70% tested positive for estrogenic activity. After the products had been washed or microwaved the proportion rose to 95%. (Chun et al. 2011)
4. Never heat foods or beverages in plastic containers
5. Avoid microwaving in plastic containers if you must microwave at all
6. Use stainless steel water bottles instead of plastic to refill water bottles.
7. Use credit cards and other forms of payment and less paper money. Skin exposure to world wide paper money  suggest to increase BPA (and Bisphenol A (BPS) – a similar xenoestrogen) levels. See HERE for more on this

References:
Ho, S-M, W-Y Tang, J Belmonte de Frausto, and GS Prins. 2006. Developmental Exposure to Estradiol and Bisphenol A Increases Susceptibility to Prostate Carcinogenesis and Epigenetically Regulates Phosphodiesterase Type 4 Variant 4. Cancer Research 66: 5624-5632.

Li DK, Zhou Z, Miao M, He Y, Qing D, Wu T, Wang J, Weng X, Ferber J, Herrinton LJ, Zhu Q, Gao E, Yuan W.Relationship between urine bisphenol-A level and declining male sexual function. J Androl. 2010 Sep-Oct;31(5):500-6.

Gail S. Prins, Wen-Yang Hu, Guang-Bin Shi, Dan-Ping Hu, Shyama Majumdar, Guannan Li, Ke Huang, Jason Nelles, Shuk-Mei Ho, Cheryl Lyn Walker, Andre Kajdacsy-Balla, and Richard B. van Breemen. Bisphenol A Promotes Human Prostate Stem-Progenitor Cell Self-Renewal and Increases In Vivo Carcinogenesis in Human Prostate Epithelium. Endocrinology, January 2014

Chun Z. Yang, Stuart I. Yaniger, V. Craig Jordan, Daniel J. Klein, George D. Bittner; Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved.Environ Health Perspect. 2011 July 1; 119(7): 989–996.

Related Links:

Science Daily
Environmental Health News
Prins et al. Study
FDA on BPA