A new scientific study published June 12, 2013 in the peer-reviewed journal Environmental Health Perspectives adds a new puzzle stone to the bisphenol A (BPA) debate. French researchers exposed dogs to small levels of BPA via different exposure pathways, and measured their blood BPA levels. Of particular interest was the free, estrogenic form of BPA before conjugation and detoxification. Compared to the standard exposure route for oral toxicity studies, delivering BPA directly under the dogs’ tongues led to significantly higher free BPA levels.
This study explains why human biomonitoring studies find free BPA, despite the compound’s rapid conjugation and clearance from the body (FPF article).
New study shows impact of oral dosing on free BPA levels. FPF report June 13, 2013.