Effects of HNTs on the morphology of developing zebrafish. Embryos were treated with different concentrations of HNTs (0, 0.25, 2.5, 5, 25, and 50 mg mL−1) starting from 6 hpf. (A–D) Percent of malformed zebrafish was analysed at 72, 96, and 120 hpf. (E) Morphology of zebrafish larvae treated with HNTs was photographed using a microscope at 48, 72, 96, and 120 hpf. The values are represented as mean ± SD (n = 24). Each bar represents the collated data of three separate experiments. The data were analysed using Graph Prim 6 for one-way ANOVA and a Tukey’s post hoc test. *** p < 0.001 versus control group. Adapted from [89].