Sperm may be harmed by exposure to BPA, study suggests

More research should focus on BPA and health effects in adults

In one of the first human studies of its kind, researchers have found that urinary concentrations of the controversial chemical Bisphenol A, or BPA, may be related to decreased sperm quality and sperm concentration.

However, the researchers are quick to point out that these results are preliminary and more study is needed. Several studies have documented adverse effects of BPA on semen in rodents, but none are known to have reported similar relationships in humans.

BPA is a common chemical that’s stirred much controversy in the media lately over its safety. Critics say that BPA mimics the body’s own hormones and may lead to negative health effects. BPA is most commonly used to make plastics and epoxy resins used in food and beverage cans, and people are exposed primarily through diet, although other routes are possible. More than 6 billion pounds of BPA are produced annually.

The new study suggests that more research should focus on BPA and health effects in adults, says John Meeker, assistant professor of Environmental Health Sciences at the University of Michigan School of Public Health.

Meeker is the lead author on the study, along with Russ Hauser, the Frederick Lee Hisaw Professor of Reproductive Physiology at Harvard School of Public Health. Colleagues at Massachusetts General Hospital and the U.S. Centers for Disease Control and Prevention also contributed to the research.

“Much of the focus for BPA is on the exposures in utero or in early life, which is of course extremely important, but this suggests exposure may also be a concern for adults,” Meeker said. “Research should focus on impacts of exposure throughout multiple life stages.” Meeker and Hauser recruited 190 men through a fertility clinic. All gave spot urine samples and sperm samples the same day. Subsequently, 78 of the men gave one or two additional urine samples a month apart. Researchers detected BPA in 89 percent of the urine samples.

Researchers measured sperm concentration, sperm motility, sperm shape and DNA damage in the sperm cell.

“We found that if we compare somebody in the top quartile of exposure with the lowest quartile of exposure, sperm concentration was on average about 23 percent lower in men with the highest BPA,” Meeker said.

Results also suggested a 10 percent increase in sperm DNA damage.

The results are consistent with a previous study by Meeker and Hauser suggesting that certain hormones, specifically FSH (follicle-stimulating hormone) and Inhibin B, are elevated or decreased in relation to BPA, respectively, a pattern consistent with low sperm production and development.

Meeker stressed that further study is necessary due to the study’s relatively small sample size and design.

“The study from which these data came is currently in progress,” Hauser said. “With a larger sample size and enhanced study design, we will be able to more definitively investigate this preliminary association in the near future.”

Reference:

University of Michigan, Sperm may be harmed by exposure to BPA, study suggests, ANN ARBOR, Mich., Aug. 3, 2010.

Related EMM Articles about BPA:

Lawsuit Seeks to Ban BPA from Food Packaging

NRDC Sues Food and Drug Administration for Failure to Regulate Toxic Chemical

WASHINGTON – - The Natural Resources Defense Council filed a lawsuit against the Food and Drug Administration for its failure to act on a petition to ban the use of bisphenol A (BPA) in food packaging, food containers, and other materials likely to come into contact with food. BPA, a hormone-disrupting chemical linked to serious health problems, poses a particular risk to fetuses, infants and young children. NRDC filed today’s lawsuit in U.S. Court of Appeals for the D.C. Circuit.

In October 2008, NRDC petitioned the FDA to prohibit the use of BPA in food packaging to prevent the toxic chemical from contaminating food. The FDA has failed to take action in response to the petition for more than 18 months, although the agency expressed concern about the effects of early life exposure to BPA on brain development and the prostate gland of fetuses, infants, and children.

BPA is found in wide variety of products, including the lining of liquid infant formula cans, soda or beer cans, fruit or vegetable cans, and pizza boxes as well as consumer products made from polycarbonate plastics, including baby bottles, sippy cups, and reusable water bottles. More than 93 percent of the general population has some BPA in their bodies, primarily from exposure through food contamination and other preventable exposures.

“BPA-free alternatives are already available and on the market. The FDA has no good reason to drag their feet on banning it,” said Dr. Sarah Janssen, a senior scientist in the Environment and Public Health program at NRDC. “It’s upsetting that food is most people’s primary source of exposure to BPA. The FDA should act now to eliminate this unnecessary risk.”

A growing amount of scientific research has linked BPA exposure to altered development of the brain and behavioral changes, a predisposition to prostate and breast cancer, reproductive harm, diabetes, obesity, and cardiovascular disease.

“The FDA has failed to safeguard the food supply and protect the public from harm,” said Aaron Colangelo, an attorney with NRDC. “The FDA’s failure to regulate this chemical in food packaging in unjustified, and so we are forced to ask the court to intervene and order the agency to take action

Literature:

NRDC, Natural Resources Defense Council, Release – Lawsuit Seeks to Ban BPA from Food Packaging, WASHINGTON, June 29, 2010.

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The Natural Resources Defense Council is a national, nonprofit organization of scientists, lawyers and environmental specialists dedicated to protecting public health and the environment. Founded in 1970, NRDC has 1.3 million members and online activists, served from offices in New York, Washington, Chicago, Los Angeles, San Francisco and Beijing.

60 Scientists and NGOs Sound Joint Warning on Plastics Chemical

Scientists and NGOs concerned about the health impacts of bisphenol A

PRESS RELEASE, 23rd JUNE 2010

An unprecedented 60 scientists and international environment, health and women’s organisations from around the globe have jointly written to the European Food Safety Authority (EFSA) stating that

“action is necessary to reduce the levels of Bisphenol-A (BPA) exposure, particularly in groups at highest risk, namely young infants and pregnant mothers.”

[Quotes from some of the participating scientists and NGOs can be found towards the end of this release.]

In total, 41 NGOs and 19 scientists from 15 countries from across the globe (including 9 from the UK) have signed the letter. The letter comes on the eve of a new scientific opinion to be released by the EFSA on the safety of Bisphenol A in food contact materials expected in early July 2010. EFSA was requested by the European Commission to assess the latest science on Bisphenol A, and if necessary, to update the existing Tolerable Daily Intake (TDI) (a specific amount in food or drinking water that can be ingested (orally) over a lifetime without an appreciable health risk).

Bisphenol A is a mass produced chemical used in the manufacture of polycarbonate plastics that are clear and nearly shatter-proof. It can be found in plastics used for food and beverages, such as baby bottles, sports water bottles, as an epoxy resin in canned food and drinks, plastic food storage containers, tableware and in other products, including dental sealants, and has been found to leach into food and drink.

There have been long standing concerns about the health impacts of bisphenol A, due to scientific studies that have shown it has hormone disrupting effects at extremely low levels of exposure. Human bio-monitoring studies have shown that the vast majority of people in developed countries are exposed to Bisphenol-A.

EFSA’s previous opinions in 2007 and 2008 predominantly relied upon a handful of industry backed scientific papers that have expressed no concerns about our levels of BPA exposure. The letter from scientists and NGOs highlights scientific criticism in academic journals regarding these papers as compared to the “several hundred peer reviewed scientific papers have been published that have highlighted potential adverse health effects associated with BPA exposures”

The letter also draws attention to some of the new studies which have raised risks of exposure relating to a potential increased likelihood of developing ‘diabetes’, ‘developmental programming’ and ‘breast cancer’. Bisphenol A exposure at environmentally relevant levels commonly found in the environment in developed countries has also been repeatedly linked by independent university – based scientists to a number of other serious chronic health conditions.

Despite EFSA’s pivotal position in setting chemical food safety levels across the EU, Sweden and Germany have become the third and fourth most recent EU member states, alongside France and Denmark, to take action ahead of the EFSA review.

Andreas Carlgren, Sweden’s Environment Minister stated, on 11th May 2010, that

“If the EU will not quickly forbid the hormone disrupting substance bisphenol in baby-bottles Sweden will precede with a national prohibition.”

The President of the German Federal Environment Agency on the 9th June also broke from EFSA policy by issuing new guidance calling on

“manufacturers, importers and users of bisphenol A to use alternative substances that pose less risk to human health and the environment in all areas of use that significantly contribute to exposure”.

Regulators in Canada and the USA have already taken action to limit BPA exposure, for example in its use in baby bottles. As yet there has been no similar action at the European Union level.

A number of EU member states continue to back a common approach across the EU on bisphenol A. Tim Smith, the head of the UK Food Standards Agency, declared in an internal FSA report on the 12th May, 2010 that he ‘considers it important to have an agreed position across the EU’ and that the FSA will only ‘revise our position in line with it the EFSA Review if it is considered necessary’, despite the action that is being taken elsewhere across the EU.

The EFSA have already delayed publication of its review, as explained on its website:

To give the European Commission an up-to-date overview of the safety of BPA, EFSA will now deliver a scientific opinion in early July rather than end of May. This is due to the need for the Panel to consider hundreds of studies in its review and analysis of the most recent scientific literature.

The letter from scientists and organisations opens by ‘welcoming this announcement’ issued at the 11th hour that EFSA has finally agreed to examine hundreds of non-industry backed scientific papers.

The letter was drafted by Breast Cancer UK and Prof. Fredrick vom Saal, Curators Professor of Biological Sciences, University of Missouri-Columbia who has been awarded by his peers for his work on Bisphenol-A and is a recognised leader in this field. The effort was also coordinated by the Brussels based Health and Environment Alliance (HEAL).

Prof. vom Saal stated in response to the publication of the letter that:

“At the heart of the debate over BPA lies an outdated set of guidelines used by regulatory agencies that are based on approaches to evaluating the safety of chemicals established over 50 years ago. Thus, 21st century research approaches have provided overwhelming scientific evidence of harm in hundreds of published reports, but these findings are being rejected for consideration because they do not conform to the outdated testing guidelines.

“This has left regulatory agencies to rely entirely on industry-funded research that used ‘approved’ testing methods that are crude and insensitive, and it is not surprising that 100% of these industry-funded studies conclude that BPA causes no harm.

“The only rational path for European regulators is to take decisive action to reduce human exposure to BPA. The overwhelming nature of the total scientific evidence mandates this as a priority.”

Clare Dimmer, Chair of Trustees Breast Cancer UK and former breast cancer patient stated:

“Breast cancer is the most common cancer across Europe and has been increasing rapidly regardless of the costly and expensive efforts made by Governments to improve screening, treatment, and increase research. It must now be time that regulators act on the science and begin to take a precautionary approach to hazardous chemicals like bisphenol-A found in our everyday products.”

Lisette van Vliet, Ph.D. the Toxics Policy Advisor at HEAL said:

“It is high time that EFSA caught up to the overwhelming science showing genuine reasons for concern about our daily exposure to BPA.”

Participating scientists and organisations were given the opportunity to provide a quote for this press release; those that responded have been included below. This does not preclude participating organisations providing their own releases, supporting statements and additional comments.

Prof. Andrew Watterson, Occupational and Environmental Health Research Group, University of Stirling, said:

“It’s worrying, considering the weight of the scientific evidence, that strong action to reduce human exposure is yet to be taken. Hundreds of academic studies have explicitly raised the risks of developmental harm to foetuses and young children from exposure to BPA and this should dictate a strong precautionary policy response from European regulators. If this is not forthcoming, the UK Government must intervene as other European countries are already doing so.”

Daniela Hoffmann, Chemicals Expert, GLOBAL 2000/Friends of the Earth Austria:

“EFSA has to finally acknowledge the overwhelming scientific evidence concerning the risk BPA poses to human health.”

Sarah Häuser, Chemicals Expert BUND / Friends of the Earth Germany:

“The existing Tolerable Daily Intake for BPA does not protect human health. In animal experiments and biomonitoring studies, BPA doses much smaller than those estimated as being safe by EFSA were linked to chronic conditions health damages like diabetes and cardiovascular diseases. It’s time to take action now.”

For further information please contact:

Hratche Koundarjian, Campaign Manager, Breast Cancer UK, Charity No: 1088047, T: 07905 911 039, E: hratche@breastcanceruk.org.uk, W: www.breastcanceruk.org.uk / www.nomorebpa.org.uk

Letter and Signatories:

Prof. Klaus-Dieter Jany, Chair of the CEF Panel

European Food Safety Authority

Largo N. Palli 5/A, 43121 Parma, Italy

23rd June 2010

Dear Prof. Jany,

We are writing to welcome the announcement on the European Food Safety Authority (EFSA) website that the CEF panel will be considering ‘hundreds of studies in its review and analysis of the most recent scientific literature’ in its review of the TDI of bisphenol-A in food contact products.

Over the last decade and a half, a substantive body amounting to several hundred peer reviewed scientific papers, have been published that have highlighted potential adverse health effects associated with BPA exposures, at internal doses relevant to levels of biologically active BPA found in humans.

As a March 2010 Review (Vandenberg et al) of 80 bio-monitoring studies of BPA in Environmental Health Perspectives makes clear;

‘The two toxicokinetic studies performed to date, which suggest that human exposure is negligible, have significant flaws and are therefore not reliable for risk assessment purposes.’

However, in its prior risk assessments of BPA, EFSA only relied on a small number of studies rather than the much larger number that the United States Food and Drug Administration recently recognised as valid and of high utility in its risk assessment of BPA, and which led the FDA to express concern about the health hazards posed by BPA.

Only a tiny minority of studies have articulated that BPA exposure is completely safe, and many of these research papers have been criticised in academic commentaries and responses as having serious flaws, but it is these few flawed studies that EFSA previously relied on to declare BPA safe.

For example, a letter co-authored by 24 scientists published in the February 2010 edition of Toxicological Sciences states;

‘Publishing studies that conclude no harm in response to low doses of endocrine disrupting chemicals, when the studies did not include a positive control (Tyl et al., 2002), included inappropriate doses of positive controls (Ryan et al., 2009; Tyl et al., 2008), or included positive controls that showed no effect (Cagen et al., 1999), is inappropriate in peer-reviewed journals (Myers et al., 2009a,b; vom Saal and Welshons, 2006). Such studies violate basic principles of study design.’

Many scientific studies are now calling into question the safety of BPA. For example, a recent study has highlighted that BPA may contribute to metabolic disorders relevant to glucose homeostasis, and suggests that BPA may be a risk factor for diabetes (Alonso-Magdalena et al., 2010). Moreover, experiments at Yale university report that BPA may induce altered developmental programming (Bromer et al.,2010), and Doherty et al (2010) of Yale university have published a study which raises the concern about epigenetic effects of BPA on the regulation of the mammary gland, with potential implications for breast cancer risk. Endometriosis is also a concern as work by Signorile et al (2010) highlights that pre-natal exposure of mice to bisphenol-A causes an endometriosis-like response in female offspring.

It is therefore our opinion that any objective and comprehensive review of the scientific literature will lead to the conclusion that action is necessary to reduce the levels of BPA exposure, particularly in groups at highest risk, namely young infants and pregnant mothers.

There are an increasing number of countries that are either already committed to this course of action, or have signalled that they will soon be undertaking similar measures.

We share the concerns of these Governments and regulators and believe that reducing BPA exposure to these groups is both scientifically sound and in the best interest of public health.

As such, we call on you as the Chair of the CEF panel and the CEF Committee Members in their ongoing review to include all relevant studies, including bio-monitoring studies, and based on that evidence we conclude that there is a strong scientific mandate for action.

Yours sincerely,

  1. Benson Akingbemi, Associate Professor, Department of Anatomy, Physiology and Pharmacology, Auburn University, Auburn, USA.
  2. Prof. Dr. Ibrahim Chahoud, Institute of Clinical Pharmacology and Toxicology, Dept. of Toxicology, Charité – Universitätsmedizin Berlin
  3. André Cicolella, Dipl Eng chemist-toxicologist.
  4. Prof. Patricia Hunt, Meyer Distinguished Professor, School of Molecular Biosciences, Washington State University
  5. Prof. Maricel V. Maffini. Ph.D. Research Assistant Professor. Department of Anatomy and Cellular Biology, Tufts University School of Medicine
  6. Jane Muncke, Ph.D, Environmental Toxicologist, Emhart Glass SA, Switzerland.
  7. John Peterson Myers, Ph.D., Chief Scientist, Environmental Health Sciences, Charlottesville VA.
  8. Angel Nadal, PhD, Professor of Physiology, Instituto de Bioingeniería and CIBERDEM, Universidad Miguel Hernández de Elche, Spain.
  9. Dr John Newby, Medical Information Scientist for the Cancer Prevention Society and Former Member of the Developmental Toxico-Pathology Research Group, Department of Human Anatomy & Cell Biology, Faculty of Medicine, University of Liverpool.
  10. Prof. Jörg Oehlmann, Goethe University Frankfurt am Main, Institute for Ecology, Evolution and Diversity.
  11. Prof. Gail S. Prins, PhD, Professor of Physiology, Department of Urology, University of Illinois at Chicago.
  12. Prof. Fredrick vom Saal, Curators Professor of Biological Sciences, University of Missouri-Columbia.
  13. Prof. Pietro Giulio Signorile, President of the Italian Endometriosis Foundation.
  14. Prof. Ana M Soto, MD, Department of Anatomy and Cell Biology, Tufts University, School of Medicine.
  15. Prof. Hugh S. Taylor, M.D., Professor of Molecular, Cellular and Developmental Biology, Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University.
  16. Laura N. Vandenberg, PhD, Postdoctoral Fellow, Center for Regenerative and Developmental Biology, Tufts University.
  17. Prof. Cheryl S. Watson, PhD, Professor, Biochemistry & Molecular Biology Dept. University of Texas, Medical Branch, Galveston.
  18. Prof. Andrew Watterson, Occupational and Environmental Health Research Group, University of Stirling.
  19. Prof. R. Thomas Zoeller, Biology Department, Morrill Science Center, University of Massachusetts.

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  1. Action for Breast Cancer, Malta
  2. Alliance for Cancer Prevention, UK
  3. Arnika, Czech Republic
  4. Association for Environmental and Chronic Toxic Injury, Italy
  5. Austrian section of ISDE (International Society of Doctors for the Environment), Austria
  6. Breast Cancer Fund, USA
  7. Breast Cancer UK, UK
  8. BUND / Friends of the Earth Germany, Germany
  9. Cancer Prevention and Education Society, UK
  10. ChemSec –International Chemical Secretariat, International
  11. CHEM Trust, UK
  12. Chemical Sensitivity Network, Germany
  13. Clean Air Action Group, Hungary
  14. Comité pour le Développement Durable en Santé, France
  15. Danish Consumer Council, Denmark
  16. The Danish Ecological Council, Denmark
  17. Eco-Accord Program on Chemical Safety, Eastern Europe, Caucasus and Central Asia
  18. EcoAid, Germany
  19. Ecologistas en Acción, Spain
  20. Environmental Health Fund, USA
  21. Environment Illinois, USA
  22. European Environmental Bureau, EU
  23. Finnish Association for Nature Conservation, Finland
  24. Friends of the Earth Spain, Spain
  25. Global 2000 / Friends of the Earth Austria, Austria
  26. Health and Environmental Network, Europe
  27. Health Care Without Harm, International
  28. Indiana Toxics Action, USA
  29. Instituto Sindical de Trabajo Ambiente y Salud, Spain
  30. The Irish Doctors’ Environmental Association, Ireland
  31. Italian Endometriosis Foundation, Italy
  32. Plastic Planet, Austria
  33. Rachel’s Friends Breast Cancer Coalition, USA
  34. Réseau Environnement Santé, France
  35. Society for Sustainable Living, Czech Republic
  36. Unison, UK
  37. VHUE e.V., Germany
  38. Women in Europe for a Common Future, Europe
  39. Women’s Environmental Network, Scotland
  40. Women’s Voices for the Earth, USA
  41. WWF European Policy Office, Europe

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References

German Translation by CSN:

60 Wissenschaftler und NGOs appellieren an EFSA

Everyday Exposure to Dangerous Levels of Toxic Chemical BPA Unavoidable

Foods Contaminated with Chemical Linked to Chronic Diseases on the Rise

Senator Feinstein, others demand BPA ban in Food Safety Bill

(Washington, DC ) Senator Dianne Feinstein stood with environmental health advocates today on Capitol Hill to release a new report that demonstrates alarming levels of bisphenol A (BPA) in common canned foods. BPA is a synthetic sex hormone and exposure to low doses has been linked to abnormal behavior, diabetes and heart disease, infertility, developmental and reproductive harm, and obesity, which raises the risk of early puberty, a known risk factor for breast cancer.

Senator Feinstein has introduced legislation that would ban BPA in cans, in addition to other food and beverage containers. The Senator is hopeful that the Food Safety Act will include language that protects consumers from BPA exposure.

We found in our analysis that if someone is eating just one meal with at least one canned food product, their levels of BPA are as much as those that have been shown to cause health effects in laboratory animal studies,” says Bobbi Chase Wilding of Clean New York, co-author, of No Silver Lining, An Investigation Into Bisphenol A in Canned Foods, by The National Workgroup for Safe Markets, a coalition of U.S. public health- and environmental health-focused organizations.

“Six states have taken crucial first steps this year to get this hormone mimicking chemical out of our children’s food, but this report shows that there is much more to be done. Senator Feinstein’s bill will protect much more of our food from this toxic contamination,” said U.S. Public Interest Research Group Public Health Advocate Elizabeth Hitchcock.

“BPA is a bad actor chemical that should not be in contact with food we eat,” says Laura Vandenberg, PhD, Tufts University, a leading BPA researcher. “Hundreds of independent peer-reviewed scientific studies have found harm from low doses of BPA and its inexcusable the chemical is still used in food cans.”

Dr. George Lundgren, a Minnesota family physician who was biomonitored and discovered BPA in his own body, has seen an increase in suspected BPA linked health effects in his patients: “The cases of diabetes and obesity are increasing at such a rate in my own practice that diet and lack of exercise alone just can’t explain it away. And the fact that there are no labels on the products that are exposing us to a chemical that may be linked to these serious health problems and other illness is disturbing.”

“Anyone who reads this report would agree that getting BPA out of food is an urgent food safety issue that demands immediate congressional action,” said Janet Nudelman, policy director at the Breast Cancer Fund. “Fortunately the Senate has the opportunity to address this problem right now by including strong protections against food-based exposures to BPA in the Food Safety Modernization Act. This is our best chance to protect Americans, especially our kids, from this toxic chemical.”

“We commissioned this study to see what level of BPA might be consumed from canned foods in a typical, everyday American diet,” explains Mia Davis from Clean Water Action, another of the report’s co-authors, “We wanted to know if the amount of BPA found in canned foods and beverages would be enough to affect a person’s health, or the health of their child if they are pregnant.”

Mike Schade from Center for Health, Environment & Justice, also a co-author, says, “General Mills just announced that it is removing BPA from its organic tomatoes’ cans, so we know that companies that want to do the right thing, will, but we need the FDA to insure a basic level of protection for consumers.”

Sarah Janssen, MD, PhD, staff scientist, Natural Resources Defense Council says,“The levels of BPA in our food supply have been associated with a wide range of health effects. Dozens of independent scientists, including the Director of NIEHS, have advised reducing BPA exposure. It’s time for FDA to act on their advice.” NRDC filed a petition in October, 2008 asking FDA to revoke the approval of and ban BPA as a food additive. FDA has yet to rule on this petition.

BPA in canned foods is just one of thousands of ways we are exposed to dangerous chemicals in everyday products,” said Andy Igrejas, national campaign director for Safer Chemicals, Healthy Families, a coalition of 200 environmental and public health groups. “The proposed Safe Chemicals Act needs to be strengthened and passed so that people, especially children, are not bombarded with such hazards.”

Highlights:

  • Levels in canned food that are the same or similar to levels of BPA found in the urine of over 90% of Americans by the Center for Disease Control and Prevention, and cord blood of newborn babies.
  • One can of Del Monte green beans had the highest levels of BPA ever found in canned food, at 1140 parts per billion; EPA presumes BPA is safe at 50 parts per billion per day.
  • The study tested 50 cans from 19 states and Ontario, Canada for BPA contamination, including cans with fish, fruits, vegetables, beans, soups, tomato products, sodas, and milks, which together represent common ingredient and meal options for a wide range of North American consumers.
  • Test results showed there is inconsistency across brands and types of food, which prevents consumers from avoiding BPA just by looking at a label. In one case, two different cans of peas from two separate lots had an extreme difference: on had six parts per billion, while the other had over 300 parts per billion.

BPA has been banned from baby bottles and children’s sippy cups in six states (Connecticut, Maryland, Minnesota, Washington, Wisconsin, and Vermont), three counties in New York and the City of Chicago. Only Connecticut and Vermont restrict the use of BPA in cans of baby food.

Denmark has recently become the first country to enact a BPA ban and Canada has banned BPA in baby bottles while the French Senate is working to impose restrictions. Japan asked manufacturers for voluntary restriction of BPA from canned food in 1998 and saw a decline in their population’s levels of contamination.

Literature: Chemical Safety Workgroup, Release, May 18, 2010.

Read full report: NO SILVER LINNING (pdf)

Related Article:

Yale: Why BPA leached from ’safe’ plastics may damage health of female offspring

Yale scientists show how bisphenol A induces epigenetic changes in pregnant mice that cause hormonal imbalance in the later life of female progeny

Here’s more evidence that “safe” plastics are not as safe as once presumed: New research published online in The FASEB Journal suggests that exposure to Bisphenol A (BPA) during pregnancy leads to epigenetic changes that may cause permanent reproduction problems for female offspring. BPA, a common component of plastics used to contain food, is a type of estrogen that is ubiquitous in the environment.

“Exposure to BPA may be harmful during pregnancy; this exposure may permanently affect the fetus,” said Hugh S. Taylor, Ph.D., co-author of the study from Yale University School of Medicine in New Haven, Connecticut. “We need to better identify the effects of environmental contaminants on not just crude measures such as birth defects, but also their effect in causing more subtle developmental errors.”

Taylor and colleagues made this discovery by exposing fetal mice to BPA during pregnancy and examining gene expression and DNA in the uteruses of female fetuses. Results showed that BPA exposure permanently affected the uterus by decreasing regulation of gene expression. These epigenetic changes caused the mice to over-respond to estrogen throughout adulthood, long after the BPA exposure. This suggests that early exposure to BPA genetically “programmed” the uterus to be hyper-responsive to estrogen. Extreme estrogen sensitivity can lead to fertility problems, advanced puberty, altered mammary development and reproductive function, as well as a variety of hormone-related cancers. BPA has been widely used in plastics and other materials. Examples include use in water bottles, baby bottles, epoxy resins used to coat food cans, and dental sealants.

“The BPA baby bottle scare may be only the tip of the iceberg.” said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. “Remember how diethylstilbestrol (DES) caused birth defects and cancers in young women whose mothers were given such hormones during pregnancy. We’d better watch out for BPA, which seems to carry similar epigenetic risks across the generations. ”

Author: FASEB* – Federation of American Societies for Experimental Biology, Why BPA leached from ’safe’ plastics may damage health of female offspring, 25-Feb-2010.

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* FASEB comprises 23 societies with more than 90,000 members, making it the largest coalition of biomedical research associations in the United States