Bisphenol-A (BPA) is an industrial chemical found in everything from food-can linings to cigarette filters to retail receipts. Nationwide testing by the Centers for Disease Control and Prevention found it in "nearly all" of its subjects. A growing body of research has established BPA as an endocrine-disrupting chemical that does harm at tiny doses. But is BPA no big deal, after all?
That's the message of a presentation given at the annual American Association for the Advancement of Science last month by Justin Teeguarden, a scientist with the Pacific Northwest National Laboratory, a lab that operates under contract with the US Department of Energy. According to a PNNL press release about the presentation, Teeguarden analyzed 150 BPA exposure studies and found that "people's exposure may be many times too low for BPA to effectively mimic estrogen in the human body." The study's funder, the press release adds, was the US Environmental Protection Agency.
Teeguarden's presentation drew wide media attention. The Guardian, the Wall Street Journal, Agence France-Presse, and the Independent all weighed in with comforting reports about the possibly innocuous nature of BPA. Writing on his Discover Magazine blog, Keith Kloor even chided me for not mentioning Teeguarden's work in my post last week about a recent study on BPA and other harmful chemicals.
Teeguarden's assessment has not been published—in a peer-reviewed journal or anywhere else
But before you dust off that old BPA-laden sippy cup for your kid, it's worth digging a little deeper into the source. First of all, all of those media reports neglected to mention that Teeguarden's assessment has not been published—in a peer-reviewed journal or anywhere else.
Teeguarden declined to speak to me but did answer some questions over email. I asked him if his study had been submitted for publication. "Not published yet," he replied. I pressed him on the question of whether it had been submitted for publication. He didn't respond. When I asked him if he would email me a copy of the Powerpoint presentation he gave at the AAAS conference, he replied, "Happy to share post acceptance," meaning, I assume, that he would turn it over once it had been accepted for publication.
The lack of publication combined with Teeguarden's refusal to release a presentation he has delivered in a public forum make it extremely difficult to assess his project. Laura Vandenberg, a postdoctoral fellow at Tufts who has published research finding significant levels of BPA in human blood, told me that it's "highly unusual" for an unpublished work to generate so much attention. When a reporter asks her to comment on a study, she told me, "what I normally do is to ask for a copy of the manuscript," she said. In this case, of course, there is no manuscript available.
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