Fig. 1

Trinitrotoluene (TNT) in pink water causes developmental defects in zebrafish. (A) Bright-field lateral view of embryos treated with pink water. Embryos were exposed to pink water containing TNT at 0 µg/mL (a,a?), 1.35 µg/mL (b,b?), 2.70 µg/mL (c,c?), and 13.5 µg/mL (d,d?) from 5 till 29 hpf (a?d, scale bar 250 µm) or 53 hpf (a??d?, scale bar 500 µm) and imaged using a stereoscope. Defects in pigmentation were evident at 29 hpf (a?d, arrow for eye color, arrowhead for body pigment, 3.2× magnification) and at 53 hpf (a??d?, arrow for abnormal heart, arrowhead for body pigment, 2.5× magnification). Morphological changes in body shape and a defect in blood circulation (split arrowhead) were observed in embryos treated with pink water containing 13.5 µg/mL of TNT at 53 hpf (d?). 5/29 hpf, treatment starting at 5 hpf, observation at 29 hpf; 5/53 hpf, treatment starting at 5 hpf, observation at 53 hpf; (B) Dorsal views of embryos treated with pink water from 38?56 hpf. (a?d) Embryos show a dose-dependent pigmentation defect. Less pigment is visible in the eye (arrow) and trunk melanocytes (arrowhead). 8× magnification, scale bar 250 µm. 38/56 hpf, treatment starting at 38 hpf, observation at 56 hpf; (C) Embryos treated with TNT at 0 µg/mL (a), 1.20 µg/mL (b), 2.90 µg/mL (c), and 5.80 µg/mL (d) from 5 hpf had similar phenotypes to embryos treated with pink water, including pigmentation defect (arrowhead), abnormal heart (arrow), and defective blood circulation (split arrowhead). 5/53 hpf, treatment starting at 5 hpf, observation at 53 hpf, scale bar 500 µm.