Still No Evidence for Endocrine Disruption

By ACSH Staff — Aug 30, 2010
BPA has long been blamed by environmental activists for supposedly mimicking the hormone estrogen (although scientists say its estrogenic effects are akin to eating tofu). Now researchers are trying to argue the chemical raises testosterone. A study of 715 Italian men and women aged 20 to 74 published in Environmental Health Perspectives found that men with the highest levels of BPA in their urine also had an increase in their blood testosterone concentrations although all the hormone levels still remained within normal range.

BPA has long been blamed by environmental activists for supposedly mimicking the hormone estrogen (although scientists say its estrogenic effects are akin to eating tofu). Now researchers are trying to argue the chemical raises testosterone. A study of 715 Italian men and women aged 20 to 74 published in Environmental Health Perspectives found that men with the highest levels of BPA in their urine also had an increase in their blood testosterone concentrations although all the hormone levels still remained within normal range.

WebMd Health News quoted ACSH s Dr. Elizabeth Whelan on the the study results:

It is no surprise that BPA was measurable in urine, but as to BPA being causally related to an increase in testosterone, the authors note that their evidence does not prove causation. There is no reason to believe that trace environmental exposures to BPA would affect testosterone levels any more than eating a meal consisting of natural soy, which is a potential natural endocrine modulator.

Study researcher Dr. Tamara Galloway concludes that BPA is what s known as an anti-androgen even though it remains unproven if BPA actually affects testosterone levels or has any health effects at all.

This is the first that I ve ever heard of such a theory, says ACSH s Dr. Gilbert Ross. I am completely unaware of any medical basis for saying that if you give someone an anti-androgen, their testosterone levels will rise.

Dr. Ross further notes that this study overlooked two critical points. First, the fact that they found BPA in the urine of 95 percent of Italian men is not surprising and does not indicate that it s toxic. Secondly, the anti-androgenic potency of BPA is minute compared to other hormonally active substances in the body. Clearly, these authors started with an answer and worked backward to come up with eccentric theories as to why BPA might be harmful even though no actual data supports these claims.I found it disturbing that the expert commentaries paint this study as important, without taking note of the fact that no hormonal abnormalites were detected none.