Researchers also found a proportionately higher concentration of free BPA—as opposed to the conjugated forms modified by the body for elimination—further showing that in fetuses the ability to eliminate the chemical from the body is not the same as in adults.
"The general message from our research is that people have to be cognizant of the fact that the adult body may be able to deal with a particular exposure but a developing fetus may not," said Muna Nahar, doctoral student in the School of Public Health's Department of Environmental Health Sciences and first author on the paper.
Previous animal studies have associated BPA with breast and prostate cancer, and reproductive and behavioral abnormalities. Some research on effects to human health has tied BPA to cardiovascular disease, miscarriage, decreased semen quality and childhood behavioral issues. The chemical also may impact metabolism, diabetes and obesity, although more studies are required to determine its effects.
Prior research on BPA—a chemical used in many consumer products, including plastic bottles and metal food and beverage cans—has measured concentrations of the chemical in urine. About 95 percent of those who have been tested in a nationally representative health survey study show some level of BPA, but the research to date had yet to firmly establish the presence of the chemical in tissues.
Understanding the internal dose is essential to determine adverse effects on health, the researchers say. BPA can reach the body through ingestion, inhalation and by contact with the skin.
Nahar and colleagues Dana Dolinoy of the U-M School of Public Health and Chunyang Liao and Kurunthachalam Kannan of the Wadsworth Center at the New York State Department of Health studied the livers of 50 first- and second-trimester fetuses, using high-performance liquid chromatography and mass spectrometry. They found wide variances in how much BPA was present in livers, with some fetuses showing high levels of exposure.
"The finding of free BPA in fetuses is significant," said Dana Dolinoy, the John G. Searle Assistant Professor of Environmental Health Sciences and senior/corresponding author of the study.
After measuring a three-times-higher concentration of free BPA than the conjugated forms in the fetal livers, the researchers then examined the enzymes responsible for metabolizing the chemical and compared them with those at work in adult male and female livers.
"Our research shows that the argument that it's so rapidly metabolized is not true in fetuses," Dolinoy said.
The study appears online in the Journal of Biochemical and Molecular Toxicology, which in early 2013 will publish a special print issue focusing on the National Institute of Environmental Health Sciences Outstanding New Environmental Scientist Award (ONES) projects. Dolinoy was awarded a five-year ONES grant in 2009 for the project titled "In Utero Exposure to Bisphenol A: Effects on the Fetal Epigenome."
Dana Dolinoy: www.sph.umich.edu/iscr/faculty/profile.cfm?uniqname=ddolinoy
Muna Nahar: http://research.sph.umich.edu/person.cfm?deptID=2&groupID=32&ownerID=478
School of Public Health: www.sph.umich.edu/index.htmlView a Risk Bites video that explains BPA: http://youtu.be/219JRH3dEwg
Laurel Thomas Gnagey | Newswise
An ounce of prevention: Research advances on 'scourge' of transplant wards
28.08.2015 | University of Wisconsin-Madison
Hypoallergenic parks: Coming soon?
27.08.2015 | American Society of Agronomy
A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.
The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...
A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).
Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...
In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.
These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...
Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.
For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...
It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.
Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...
20.08.2015 | Event News
20.08.2015 | Event News
19.08.2015 | Event News
28.08.2015 | Physics and Astronomy
28.08.2015 | Health and Medicine
28.08.2015 | Life Sciences