by: S. L. Baker
(NaturalNews) Don't worry, be happy. Just ignore the fact that countless researchers have warned time and time again that the chemical bisphenol A (BPA for short) is a major hormone disruptor and is a huge threat to human health. After all, we must all be safe because the U.S. Food and Drug Administration (FDA) would have banned the stuff long before now if there was really any problem, right?
Here's the latest breaking news on what has become an environmental nightmare for both humans and possibly wildlife while the FDA does nothing but express "some concern" that BPA might not be perfectly safe.
University of Missouri researchers have evidence that BPA causes male deer mice to lose their masculinity and behave more like females. In fact, female mice sense something isn't quite "right" about BPA exposed males and don't want to mate with them.
The scientists conclude that exposure to BPA during human development could also be wreaking havoc on hormones and distorting and disrupting behavioral and cognitive traits that are unique to each sex and important in reproduction.
"The BPA-exposed deer mice in our study look normal; there is nothing obviously wrong with them. Yet, they are clearly different," said Cheryl Rosenfeld, associate professor in biomedical sciences in the College of Veterinary Medicine and investigator in the Bond Life Sciences Center, in a statement to the media. "Females do not want to mate with BPA-exposed male deer mice, and BPA-exposed males perform worse on spatial navigation tasks that assess their ability to find female partners in the wild."
"This study sets the stage for BPA researchers to examine how BPA might differentially impact the behavioral and cognitive patterns of boys versus girls," Rosenfeld added. "Investigators looking for obvious BPA-induced differences, such as chromosome deletions or DNA mutations, could be missing subtle behavioral differences that eventually lead to long-term adverse outcomes, including demasculinization of male behaviors with a decreased reproductive fitness."
For the new study, the researchers fed female deer mice a BPA-supplemented diet for two weeks prior to breeding and throughout lactation. The mothers were given a dosage equivalent to what the U.S. Food and Drug Administration considers a non-toxic dose for pregnant women to ingest.
When the deer mice offspring were weaned at 25 days of age, they were fed on a non-supplemented BPA diet. Then, after the rodents matured into adults, their behavior was tested to study each mouse's ability to navigate a maze to safety.
Male deer mice normally have an enhanced spatial navigational ability. It's important because it allows them to find female mates that are dispersed throughout the environment. Female deer mice do not need to search for mates so their navigational abilities have not been enhanced by evolution. But when the University of Missouri researchers tested the navigational skills of male mice that had been exposed to BPA early in their development, something was terribly wrong.
Each male mouse had two five minute opportunities per day, for seven days, to try to find their way in to a home cage through one of several holes placed around the edge of an open maze.
What's more, the maze was marked with a set of visible navigational cues to help the animals. Yet many of them could not find the exit. On the other hand, all the male mice who had not been exposed to BPA found the correct exit quickly – some on the first day.
Adding to the strong evidence that the BPA dramatically changed the ability of the male mice to navigate normally, the scientists found that the non-BPA exposed mice quickly learned the most direct approach to finding the correct hole, while the exposed males appeared to sort of randomly and inefficiently wander around looking.
The female deer mice also were turned off by potential mates who had been exposed to BPA. In a mate choice experiment, the scientists measured the females' level of interest in a stranger male by observing specific behaviors, such as nose-to-nose sniffing and the amount of time the female spent checking out her potential partner. According to Dr. Rosenfeld, both non-exposed and BPA-exposed females strongly preferred control males over BPA-exposed males.
"These findings presumably have broad implications to other species, including humans, where there are also innate differences between males and females in cognitive and behavioral patterns," Rosenfeld said in the media statement. "In the wide scheme of things, these behavioral deficits could, in the long term, undermine the ability of a species such as the deer mouse to reproduce in the wild. Whether there are comparable health threats to humans remains unclear, but there clearly must be a concern."
This research, which is set for publication in the Proceedings of the National Academy of Sciences, is the latest in a mounting and damning array of studies showing the dangers of BPA. For example, as NaturalNews has covered extensively, BPA has been found to cause precancerous conditions, kidney and developmental problems in animals.
And research published in the Journal of the American Medical Association (JAMA) showed that humans could be walking time bombs of health problems related to the ingestion of BPA, which is found in virtually all packaged foods. The JAMA study reported for the first time that the chemical might well be linked to the epidemic of heart disease and diabetes in this country.