While only few in vitro studies showed that BPF [36, 37] and BPS [19] increase the proliferation of breast cancer cell lines (MCF-7 or MCF-7 CV), several showed that BPA increases the proliferation of these same cell lines [4, 5, 9, 36–41] and few investigated whether this increase is ER-dependent [19, 40]. Here, ESR1 is linked to breast cancer.