Estrogenic activity of dental materials and bisphenol-A related chemicals in vitro

Twenty-eight chemicals used as dental materials and bisphenol-A related chemicals were diluted with DMSO to concentrations ranging from 10(-7) to 10(-3) M and tested for estrogenicity. Bisphenol-A (BPA), bisphenol-F (BPF) and bisphenol-A-bischloroformate (BPACF) showed estrogenic activity using the yeast two-hybrid system, and BPA, BPF, BPACF and bisphenol-S (BPS) showed estrogenic activity using the fluorescence polarization system. However, none of the remaining chemicals and none of the dental materials showed any activity at concentrations between 10(-7) and 10(-3) M. Although BPA, BPF, BPACF, bisphenol-A-dimethacrylate and BPS showed estrogenic activity in the E-screen test, the remaining chemicals did not. Thus, most of the chemicals showed consistent results, either positive or negative, by the three testing methods, while two chemicals showed conflicting results. Further studies, together with in vivo and epidemiological examinations, are required. Elucidation of the structure-activity relationships of these chemicals is also needed to estimate the estrogenicity of a chemical from its structure.