BPA Makes Sperm Less Spunky: Study

(CBS/AP) Does exposure to bisphenol-A (BPA) make sperm less spunky?

A new study shows that men exposed to high levels of the controversial chemical - which is found in many plastics - had low sperm counts and decreased sperm motility. 

Whether the poor semen quality translates to reduced fertility is unknown. Study author Dr. De-Kun Li, a scientist at the Kaiser Permanente Division of Research in Oakland, Calif., noted that even men with extremely low sperm counts can father children.

But Li said finding that BPA may affect sperm is troubling because it echoes studies in animals and follows his previous research in the same men that linked BPA exposure with sexual problems.

The study was published online today in the journal Fertility and Sterility.

Andrea Gore, a pharmacology and toxicology professor at the University of Texas who was not involved in the research, called it an important but preliminary study.

The results "are at least suggestive of the possibility that BPA may be one of the compounds that are causing some of these changes" in sperm, she said. But Gore said stronger evidence is needed to prove that BPA is indeed the culprit.

BPA is used to make resins and strengthen plastics and is found in many consumer products: hard plastic bottles, metal food container linings, dental sealants and eyeglasses. Most Americans' urine contains measurable levels of BPA.

Studies in animals have linked the chemical with reproductive problems and cancer.

Steven Hentges of the American Chemistry Council, an industry group, said the study in China "is of limited relevance" to U.S. consumers, who typically are exposed to very low BPA levels that pose no health threat.

The study involved 130 Chinese factory employees who worked directly with materials containing BPA and 88 workers who didn't handle it and whose exposure was similar to that of typical American men.

Low sperm counts were found in workers who had detectable levels of BPA in their urine. Poor sperm quality was two to four times more prevalent among these men than among workers whose urine showed no sign of BPA. The lowest sperm counts were in men with the highest levels of BPA.

The FDA has been evaluating the chemical's safety. In an e-mailed statement, the agency said it is working with the National Institutes of Health and others "to advance scientific understanding of BPA and inform our decisions."

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