Prior posts have followed the debate over BPA and its potential problems. In a recently reported study, researchers have raised a new issue, the activation of estrogen-related genes.
Exposure of animal and cell models to doses of BPA below the recommended tolerable daily intake (TDI) of 50 µg/kg/day have been shown to alter specific estrogen-responsive gene expression, but this has not previously been shown in humans. Researchers studied 96 adult men and examined in-vivo expression of 6 estrogen-, estrogen-related- and androgen- receptor genes in peripheral blood leukocytes (white blood cells; see http://en.wikipedia.org/wiki/White_blood_cell).
The study found that even at BPA levels below the TDI certain estrogen-related receptors were expressed. The results were consistent even when taking into account potential confounding factors such as obesity, serum lipid concentrations, and white cell sub-type percentages. The conclusion drawn, then, was that activation of receptor-mediated pathways by BPA provides evidence that BPA is likely to function as a xenoestrogen ("foreign" estrogens that have estrogenic effects on a living organism; see http://en.wikipedia.org/wiki/Xenoestrogen).