November 11, 2009

Study Links Heavy BPA Exposure To Sexual Dysfunction In Men

Researchers reported on Wednesday that male factory workers in China who got very high doses of the chemical BPA, or bisphenol A, had high rates of sexual problems, The Associated Press reported.

The study, which adds to concerns about BPA's effects on most consumers, showed that heavy exposure to BPA -"“ which is widely used in hard plastic bottles -- was linked to impotence and lower sexual desire and satisfaction.

Researcher Dr. De-Kun Li said the men in the study experienced BPA levels about 50 times higher than those faced by typical American men.

"We don't know whether more typical doses have similar effects," he added.

Li, a reproductive and perinatal epidemiologist at Kaiser Permanente's research division in Oakland, warned that the finding shouldn't alarm people. But he said it would be prudent to limit exposure to BPA while scientists look for any effects from lower doses.

Meanwhile, the U.S. government recently announced new funding for research into BPA's effects.

Experts say some 90 percent of the U.S. population carries detectable levels of BPA in the urine, as it is used in a wide variety of consumer products, including some hard plastic bottles and metal food or beverage cans. Several makers of baby bottles recently said they had stopped using the chemical.

BPA exposure might harm the reproductive and nervous systems, and possibly promote prostate and breast cancers, according to scientists. A preliminary study last year linked BPA to possible risks for heart disease and diabetes.

Trace amounts of BPA that leach out of bottles and food containers are not dangerous, according to FDA investigation last year. However, the administration is now reviewing that stance after criticism from its scientific advisers.

Li and colleagues studied 164 factory workers in China who were exposed to high levels of BPA on the job and compared them to 386 other men in the same town who either worked at other factories or were married to factory workers.

BPA exposure was measured through air sampling, and researchers interviewed the workers about their sexual functioning.

They found that men with high BPA exposure were about four times as likely to report trouble achieving erections, about seven times as likely to say they had difficulty ejaculating, and about four times as likely to report low sex drive or low satisfaction with their sex lives than the other workers.

Linda Birnbaum, director of the National Institute of Environmental Health Sciences, who was not involved in the research, said the effects are dramatic and pretty clearly related to the exposure.

She said the finding fits in with animal studies and should be followed up by research in the general population. Last month, her institute said it would spend more money on BPA-related research.

"The work is probably not very relevant for consumers," said Steven Hentges, a BPA expert and official with the American Chemistry Council, an industry group.

He said the reported 50-fold difference in exposure seems to be an underestimate because of how it was calculated. He also said the workers inhaled BPA or got it on their skin.

Hentges said consumers get it through diet instead, which lets the body detoxify it.

The workers probably were exposed not only through inhalation and skin contamination but also by swallowing BPA powder that contaminated their food, Li said.
He said he didn't know which route was most prominent in the Chinese factories.

The full study was published online Wednesday by the journal Human Reproduction. The National Institute of Occupational Safety and Health financed the work.


On the Net: