Combined Effects of Temperature Changes and Bisphenol a on the Embryonic Development of Zebrafish (Danio rerio)

Water pollution by heat and organic matter is a global concern. Bisphenol A (BPA), an organic synthetic compound which is used as a raw material in the manufacture of many plastic products. It was found in water and has the potential to bioaccumulate and disrupt the endocrine system. This study evaluated the simultaneous influence of BPA and temperature changes on zebrafish embryos (Danio rerio). Embryos (0 day) were exposed in BPA (2.5 - 25 mg/L) at three temperature regimes: 23°C, 28°C (control) and 33°C. The amount of embryonic death, malformations (hematoma, pericardial edema) were recorded at 24 hours post fertilization (hpf), 48hpf, 72hpf and 96hpf. The results showed that embryo mortality and malformation rate increase depending on BPA concentration and temperature. At 96hpf endpoint, lethal concentration (LC50) and morphological effective concentration (mEC50) of 23°C, 28°C, 33°C were obtained as follows: LC50 = 14.886 mg/L and EC50 = 10.421 mg/L; LC50 = 16.732 mg/L and EC50 = 9.336 mg/L; LC50 = 7.627 mg/L and EC50 = 7.731 mg/L. The toxic of BPA at 33oC was higher that of control condition indicating the synergistic effect of BPA and temperature changes on the embryonic development of zebrafish. This suggests the climate change might also change the toxic effect of bisphenol A.