Individual and combined developmental toxicity assessment of bisphenol A and genistein using the embryonic stem cell test in vitro

• Bisphenol A and genistein were classified as weakly and strongly embryotoxic respectively in embryonic stem cell test.
• The combined exposure effects of BPA and GEN were evaluated using a 4 × 4 full factorial design.
• BPA and GEN have a synergistic effect on embryonic stem cells differentiation at lower dosages.

The potential developmental toxicity of environmental estrogenic endocrine disruptors have become a great concern in recent years. In this study, two typical environmental oestrogen, namely, bisphenol A (BPA) and genistein (GEN) were investigated for potential embryotoxicity using the embryonic stem cell test model. Afterwards, a 4 × 4 full factorial design and the estimated marginal means plot were performed to assess the combined effects of these two compounds.According to the linear discriminant functions and classification criteria, bisphenol A and genistein were classified as weakly embryotoxic and strongly embryotoxic respectively. As for combined effects, the overall interaction between BPA and GEN on embryonic stem cells (ESCs) differentiation was synergistic at low dosages, however, on ESCs and 3T3 cell proliferation, the predominate action was additive. Considering the actual daily intake of these chemicals, it is concluded that BPA alone might not have adverse reproductive or developmental effects on human being. However, given that BPA and GEN do have synergistic effect at low concentration, they may disturb normal embryo development together, which could result in birth defect and behavioral alterations later in life.