On January 27, 2015 the U.S. Department of Energy’s Pacific Northwest National Laboratory published a news release reporting on a new study suggesting that exposure to bisphenol A (BPA, CAS 80-05-7) via food does not create a risk for high exposures. In 2013, a study conducted in dogs led to the conclusion that human blood levels of BPA might be higher than regulatory agencies assumed because sublingual absorption had been often neglected (FPF reported). This idea became the basis for questioning the regulatory decisions. Therefore, in the new study published in the peer-reviewed journal Toxicology and Applied Pharmacology, Teeguarden and colleagues set out to determine whether BPA absorption from tissues of the mouth also increased BPA blood levels in humans. Ten male volunteers ate warmed tomato soup containing 30 μg/kg body weight dose of easily traceable deuterium labeled BPA. Serum and urine samples were collected over a 24-hour period and analyzed for BPA. The results show that soup consumption, i.e. normal eating behavior and hence typical human exposure to BPA in liquids, did not lead to higher levels of the active form of BPA in blood. Furthermore, there was no merit to hypotheses that BPA accumulates in humans, as the full dose was eliminated in urine within 24 hours. The authors stress that it was now confirmed that typical exposure to BPA in food produces picomolar to subpicomolar serum BPA concentrations in humans and not nM concentrations, as previously reported in some biomonitoring studies. Nevertheless, there could be cases, e.g. in hospitals, where plastics are used in medical procedures and exposures could therefore be higher than in the general population, Teeguarden noted. The European Food Safety Authority (EFSA) and the U.S. Food and Drug Administration (FDA) have recently reaffirmed the safety of BPA in food contact applications.
Pacific Northwest National Laboratory (January 27, 2015). “Man trumps dog: Earlier assumption about BPA exposure confirmed.”
Teeguarden, J.G. et al. (2015). “24-hour human urine and serum profiles of bisphenol A: Evidence against sublingual absorption following ingestion in soup.” Toxicology and Applied Pharmacology (published online January 22, 2015).