The effects of ionizing radiation on zebrafish development and survival. Zebrafish embryos at 6 or 24 hpf were exposed to 0, 5, 10, 15, or 20 Gy. (A, C) The proportion of viable to total zebrafish embryos at 6 and 24 hpf. 0 Gy (Control, ♦), 5 Gy (□), 10 Gy (●), 15 Gy (Δ), 20 Gy (◯), and survival were determined at 0, 24, 48, 72, 96, 120, 144, and 168 hpf. Morphology was also daily evaluated in each group (B, D). hpf, hours postfertilization.