Abstract
In this study, we investigated the toxicity of bisphenol compounds (BPs), namely, bisphenol A (BPA), bisphenol B (BPB), bisphenol E (BPE), bisphenol F (BPF) and bisphenol P (BPP) to the early life stages of medaka, and their estrogenic activity in vitro based on chemiluminescent signal intensity. The 14-d LC50 values of BPs on embryos less than 24-h post-fertilization were estimated in the range of 2800 to 28600 μg/L(BPA: 14800 μg/L, BPB: 7400 μg/L, BPE: 26000 μg/L, BPF: 28600 μg/L and BPP: 2800 μ g/L). In addition, the lowest-observed-effect concentrations of hatchability after 14-d BPs exposure were estimated as follows: BPA: 12500 μg/L, BPB: 8890 μg/L, BPE: 26670 μ g/L, BPF: 17780 μg/L and BPP: 1780 μg/L. Moreover, the time to hatching of fertilized eggs exposed to BPs for 14 days was significantly delayed at a BPF dose of 17780 μg/L. The 96-h LC50 values of BPs on 24-h-old larvae were estimated in the range between 6100 and 13900 μg/L(BPA: 13900 μg/L, BPB: 6100 μg/L, BPE: 13900 μg/L, BPF: 13300 μg/L and BPP: 2300 μg/L). On the other hand, the estrogenic activities of BPs for medaka estrogen receptor α were estimated as BPA: 0.06, BPB: 0.10, BPE: 0.03, BPF: 0.13 and BPP: 0.05 compared with estradiol-17β: 100 in the yeast two-hybrid assay. These results suggest that BPB and BPP have high toxicity to the early life stages of medaka and that the in vitro estrogenic activities of BPB and BPF were higher than that of BPA.
