Is Chemical in Plastic Robbing Men of Sex Appeal? Female mice rejected male mice exposed to chemical BPA in the womb.

June 28, 2011 -- A chemical found in common plastics may undermine a man's masculinity and his ability to attract a female, or at least that's what a new study on mice may suggest.

It is the latest research to question the health safety of the hormone-changing compound bisphenol-A, or BPA.

In the study, researchers found that female mice were not attracted to male mice that were exposed to BPA in the womb. They also noted that males exposed to the chemical in the womb were more likely to behave like females.

Researchers said female mice exposed to BPA were unaffected by the chemical.

It's possible that BPA exposure alters the males' hormone signals, researchers said, and some say the chemical exposure may have the same effect on people by altering developmental sexual traits in boys and girls.

"BPA has been shown to suppress the early production of testosterone. In short, the females can sense [the males'] compromised state and are less attracted to these males," said Cheryl Rosenfeld, associate professor in biomedical sciences at the University of Missouri and co-author of the study.

According to the Environmental Protection Agency, more than 1 million pounds of BPA are released into the environment each year, primarily uised as an ingredient to harden plastic. The chemical has been widely scrutinized, causing several consumer products, including baby bottles, water bottles and microwavable dishware made with the compound, to be taken off the shelves.

Last year, the European Union and Canada banned the use of BPA in baby bottles. Many U.S. states are following suit by considering a ban on the chemical, as well.

Chemical in Plastics Threatening Masculinity?

Last week, the American Medical Association voted to adopt a policy which recognized BPA as a chemical that interferes with human hormones. The organization now urges makers of BPA plastics to label and identify the chemical in the product.

"While the exact outcomes may differ in humans, there is reason for concern that sex-specific behavioral alterations are a significant risk following prenatal exposure to BPA," said Dr. Rodney Dietert, professor of immunotoxicology at Cornell University. "Brain, behavior and immune effects are commonly seen with developmental exposure to BPA."

In a previous study, researchers linked BPA to lower sperm counts and smaller testes in male mice. Another study reported that a female mouse had reduced pregnancy rates when she mated with a male exposed to BPA, said Dr. John Spangler, associate professor at Wake Forest University School of Medicine.

"This study adds to the increasing evidence that BPA is a toxin that we should regulate more stringently," said Spangler.

Researchers said the mice were fed food laced with BPA at levels considered safe for human exposure, but the American Chemistry Council disagreed, saying "typical human exposures are miniscule compared to the dose used in the study."

"Given the incredibly high exposure levels of BPA used in this study—a single dose level approximately 250,000 times higher than typical human intake – there is little to be learned from the authors' work," the American Chemistry Council said in a statement.