Estrogen Receptor Activation Potential of Internal Concentrations of BPA in Humans

Human exposure to BPA is widespread, but efficient first pass glucuronidation limits the bioactive fraction of BPA to ~0.1 % of total BPA. This talk will summarize published data on adult human exposure to Bisphenol A with a focus on characterizing internal exposure to the bioactive (aglycone) form of Bisphenol A in adults and children. We derive estimates of BPA serum concentrations from more than 30 human urine biomonitoring studies and external exposure estimates, representing greater than 12000 individuals across 9 countries, including adults, children, and pregnant and non-pregnant women, by applying the ratio of blood to urine concentrations of total BPA and the fraction of total serum BPA in the unconjugated form. Blood concentrations are compared to affinity constants for all estrogen receptors to determine if concentrations are high enough to cause endocrine disruption. They are not. But can this knowledge affect the public’s view of the risks posed by BPA?