Navigation Links
Perinatal bisphenol-A exposure may affect fertility
Date:12/2/2010

BOSTON (Dec. 2, 2010, 12:01 a.m. ET) 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.


'/>"/>

Contact: Siobhan Gallagher
617-636-6586
Tufts University, Health Sciences
Source:Eurekalert

Related biology news :

1. Perinatal Days and International Stillbirth Conference -- Nov.5-7
2. March of Dimes establishes 2 new perinatal bioethics awards
3. Study: Bird diversity lessens human exposure to West Nile Virus
4. Birth control has long-term effect on hormone exposure
5. Major source of radon exposure overlooked at former Ohio uranium-processing plant
6. Household exposure to toxic chemicals lurks unrecognized, researchers find
7. Study reveals effects of unconscious exposure to advertisements
8. Benefits of breastfeeding outweigh risk of infant exposure to environmental chemicals in breastmilk
9. Novel technique changes lymph node biopsy, reduces radiaiton exposure
10. Novel technique changes lymph node biopsy, reduces radiation exposure
11. Swimmers at public beaches show increased risk of exposure to contagious staph bacteria
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/6/2017)... 6, 2017 According to Acuity Market ... border authorities to continue to embrace biometric and ... 2143 Automated Border Control (ABC) eGates and 1436 ... more than 163 ports of entry across the ... achieving a combined CAGR of 37%. APC Kiosks ...
(Date:2/3/2017)... WASHINGTON , Feb. 3, 2017 A ... Identity Strategy Partners, LLP (IdSP) . Designed to ... in the complex identity market, founding partners Mark ... nearly 35 combined years just in identity expertise that ... tank and non-profit leadership. The Crego-Kephart combined expertise has ...
(Date:2/2/2017)... NEW YORK , Feb. 2, 2017  EyeLock ... has released a new white paper " What You ... The problem of ensuring user authenticity is a ... protect the authentication of users. However, traditional authentication schemes ... Biometric authentication offers an elegant ...
Breaking Biology News(10 mins):
(Date:2/23/2017)... upscale Capitol Hill neighborhood, with its swanky shops, parks and cafés, ... treatment salon to set up shop. But there,s Hair ... bistro on E Madison Ave, and CEO Maria Botham ... clinic, we pride ourselves on being a destination for parents ... stigma associated with lice. Everyone can get lice – it ...
(Date:2/23/2017)... ... 2017 , ... Today, researchers can fast-track sample collection and ... other biomarkers or SNPs of interest) using one, easy-to-collect saliva sample. With the ... between insulin and other relevant biomarkers can be extensively studied through a non-invasive ...
(Date:2/23/2017)... ... February 22, 2017 , ... Seventy-one members ... named Fellows of the Society this year, the Fellows Committee has announced. The ... of optics, photonics, and imaging as well as their service to the Society ...
(Date:2/22/2017)... 22, 2017 Scientists propose in Nature ... damage in Gaucher and maybe other lysosomal storage diseases ... costs than current therapies. An international research ... , which also included investigators from the University of ... data Feb. 22. The study was conducted in mouse ...
Breaking Biology Technology: