Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Perinatal bisphenol-A exposure may affect fertility

Exposure to a ubiquitous environmental chemical during pregnancy may impair reproductive capacity of female offspring, according to a study published online in advance of print on December 2 in Environmental Health Perspectives. Fertility decreased over time in female mice that had been exposed during fetal and neonatal (perinatal) development to doses of bisphenol-A (BPA) that were lower than or equal to human environmental exposure levels.

"Mice exposed to BPA in the womb and during nursing subsequently had fewer successful pregnancies and delivered fewer pups over the course of the study," reported one of the study's co-senior authors, Ana M. Soto, MD, professor of anatomy and cellular biology at Tufts University School of Medicine (TUSM) and member of the cell, molecular and developmental biology program faculty at the Sackler School of Graduate Biomedical Sciences.

At the highest of three doses tested, only 60% of the BPA-exposed mice had four or more deliveries over a 32-week period, compared with 95% in the unexposed control group. Decline of the reproductive capacity of the female mice in this study was not obvious at first pregnancy, when the animals were very young, but manifested later in life with a decline in number of pups born per delivery.

"This finding is important because standard tests of reproductive toxicology currently consist of assessing the success of a first pregnancy in young animals. If subsequent pregnancies are not examined, relevant effects may be missed," said co-senior author Beverly S. Rubin, PhD, associate professor of anatomy and cellular biology at TUSM and member of the cell, molecular and developmental biology and neuroscience program faculties at the Sackler School.

"In addition, the infertility effect of BPA was dose-specific in our study. The lowest and highest doses we tested both impaired fertility, while the intermediate dose did not. This phenomenon, called non-monotonicity, is a common characteristic of hormone action. In other words, chemicals have to be tested at a variety of doses in order to avoid false "no effect" results," added co-senior author Carlos Sonnenschein, MD, professor of anatomy and cellular biology at TUSM and member of the cell, molecular and developmental biology program faculty at the Sackler School.

"BPA has effects that mimic those of estrogen, a natural hormone. Fetal and neonatal exposure to BPA has been shown to have other hormone-related effects in rodents, including increased risk of mammary and prostate cancers, altered behavior, and obesity. BPA has been found in the urine of over 92% of Americans tested, with higher levels in children and adolescents relative to adults. It has also been detected in human maternal and fetal plasma," said co-first author Perinaaz R. Wadia, PhD, a research associate in the Soto/Sonnenschein laboratory at TUSM.

"Our findings are potentially of great relevance to humans because BPA is used in the production of materials people are exposed to every day, such as polycarbonate plastics and the resins used to coat the inside of food and beverage cans," said co-first author Nicolas J. Cabaton, PhD, formerly a post-doctoral fellow in the Soto/Sonnenschein laboratory at TUSM and now at the French National Institute for Agricultural Research (INRA).

The authors compared the effects of BPA to those of diethylstilbestrol (DES), a hormonally active chemical that is known to have caused reproductive impairment in women exposed during fetal life, and concluded that the effects of these two chemicals on fertility were comparable. Similar to BPA, low doses of DES had failed to cause obvious reproductive problems when evaluated only at first pregnancy as in the standard tests used by regulatory agencies to determine toxicity.

The three doses of BPA tested are within the range of human exposure and below the Environmental Protection Agency (EPA) reference dose (i.e., the maximal acceptable daily dose). "Our results suggest that a more sensitive test, like the one used in this report should be adopted by regulatory agencies in order to uncover the true risk and possible epigenetic effects of suspected endocrine disruptors," said Soto.

Additional authors include Daniel Zalko, DVM, PhD, French National Institute for Agricultural Research (INRA), Cheryl M. Schaeberle, BS, laboratory coordinator in the Soto/Sonnenschein lab; Michael H. Askenase, BS, formerly a research technician in the Soto/Sonnenschein lab; Jennifer L. Gadbois, RN, Andrew P. Tharp, BS, and Gregory S. Whitt, BS, all research technicians in the Soto/Sonnenschein lab in the department of anatomy and cellular biology at TUSM.

This study was supported by the National Institute of Environmental Health Sciences, part of the National Institutes of Health.

Cabaton NJ, Wadia PR, Rubin BS, Zalko D, Schaeberle CM, Askenase MH, Gadbois JL, Tharp AP, Whitt GS, Sonnenschein C, Soto AM. Environmental Health Perspectives. 2010. "Perinatal exposure to environmentally relevant levels of bisphenol-A decreases fertility and fecundity in CD-1 mice."

About Tufts University School of Medicine and the Sackler School of Graduate Biomedical Sciences

Tufts University School of Medicine and the Sackler School of Graduate Biomedical Sciences at Tufts University are international leaders in innovative medical education and advanced research. The School of Medicine and the Sackler School are renowned for excellence in education in general medicine, biomedical sciences, special combined degree programs in business, health management, public health, bioengineering and international relations, as well as basic and clinical research at the cellular and molecular level. Ranked among the top in the nation, the School of Medicine is affiliated with six major teaching hospitals and more than 30 health care facilities. Tufts University School of Medicine and the Sackler School undertake research that is consistently rated among the highest in the nation for its effect on the advancement of medical science.

If you are a member of the media interested in learning more about this topic, or speaking with a faculty member at the Tufts University School of Medicine, the Sackler School of Graduate Biomedical Sciences, or another Tufts health sciences researcher, please contact Siobhan Gallagher at 617-636-6586.

Siobhan Gallagher | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg

nachricht New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>