Food writer Tom Philpott has authored a March 13, 2013, Mother Jones article taking issue with a meta-analysis of bisphenol A (BPA) studies that toxicologist Justin Teeguarden recently presented at the American Association for the Advancement of Science. Funded by the U.S. Environmental Protection Agency, the meta-analysis covered 150 exposure studies and 130 toxicity studies, and ultimately concluded that “people’s exposure may be many times too low for BPA to effectively mimic estrogen in the body,” according to a recent press release issued by the Department of Energy’s Pacific Northwest National Laboratory (PPNL).
In particular, Teeguarden argued that human BPA exposure usually occurs at levels well below detection, pointing to the combined results of exposure studies apparently showing “that human blood levels of BPA are expected to be too far below levels required for significant binding to four of the five key estrogen receptors to cause biological effects.” His research also noted that the “low doses” defined in animal toxicity studies “actually span an immense range of concentrations” that for the most part fall outside current human exposures, raising questions about the accuracy of these models when applied to human health. “The term low-dose cannot be understood to mean either relevant to human exposures or in the range of human exposures. However, this is in fact what it has come to mean to the public, as well as many in the media,” Teeguarden was quoted as saying.
Philpott has countered, however, that recent media coverage of Teeguarden’s presentation failed to mention that the meta-analysis has not yet been published in a peer-reviewed journal. His review of the presentation in Mother Jones also criticized the toxicologist for his alleged industry ties and implied that the federal research laboratory PNNL, which operates under an entity known as Battelle, is not wholly independent of corporate interests since it once designed a chemical exposure framework for the American Chemistry Council.
“[I]n the past Teeguarden has received support from the plastics industry for research on BPA and other hormone disruptors—and has co-authored work with industry employed scientists,” opined Philpott in regard to Teeguarden’s previous studies funded by the American Plastics Council. “All of which is merely to point out that Teeguarden shouldn’t be thought of as a government scientist. He is a researcher who has collaborated with and been funded by the chemical industry, and works for an organization that also has worked with the chemical industry.”