Etridiazole (EDZ), a thiadiazole-containing toxic chemical, is widely used as a fungicide. Regular usage of EDZ may reach and contaminate water bodies, but its adverse effects on aquatic vertebrates have not been well studied. Therefore, the present study aimed to evaluate the harmful effects of EDZ using zebrafish (ZF) (Danio rerio) embryos. ZF embryos were treated with 3.75, 7.5, 15, 30, and 60 mg/L of EDZ. Subsequently, mortality and developmental toxicities were quantified at 24, 48, 72, and 96 h post fertilization (hpf). The results showed that embryo mortality was concentration- and time-dependent. The median lethal concentration (LC50) of EDZ at 96-h was 25.58 ± 1.49 mg/L. Besides, EDZ induced a series of morphological deformities, including abnormal somite formation, abnormal eye pigmentation, abnormal tail morphology, tail kinks, skeletal malformations (lordosis, kyphosis, and scoliosis), and yolk sac edema in a concentration-dependent manner. Among the deformities, the most significant were reduced heartbeat and increased incidence of pericardial edema. The median effective concentration (EC50) of EDZ at 96-h was 17.93 ± 2.22 mg/L and the 96-h teratogenic index (TI) value was 1.52. Taken together, these results indicate that EDZ is a teratogen, and primarily affects the cardiovascular system of ZF.

中文翻译：

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致畸和斑马鱼土菌灵的发育毒性作用（斑马鱼）胚胎

含有噻二唑的有毒化学物质-乙二唑（EDZ）被广泛用作杀菌剂。经常使用EDZ可能会到达并污染水体，但是尚未充分研究其对水生脊椎动物的不利影响。因此，本研究旨在评估使用斑马鱼（ZF）（Danio rerio）胚胎的EDZ的有害作用。ZF胚胎用3.75、7.5、15、30和60 mg / L EDZ处理。随后，在受精后24、48、72和96 h（hpf）定量测定死亡率和发育毒性。结果表明，胚胎死亡率与浓度和时间有关。EDZ在96小时的中值致死浓度（LC50）为25.58±1.49 mg / L。此外，EDZ诱发了一系列形态畸变，包括畸形的松节形成，异常的眼睛色素沉着，异常的尾巴形态，尾巴扭结，骨骼畸形（驼背，驼背和脊柱侧弯）和卵黄囊水肿，呈浓度依赖性。在这些畸形中，最明显的是心跳加快和心包水肿的发生率增加。EDZ在96小时的平均有效浓度（EC50）为17.93±2.22 mg / L，96小时致畸指数（TI）值为1.52。综上所述，这些结果表明EDZ是一种致畸剂，主要影响ZF的心血管系统。