Center for Marine Environmental Studies, Ehime University, Matsuyama, 790-8577, Japan.
Department of Life and Nanopharmaceutical Science and Department of Biology, Kyung Hee University, Seoul, 130-701, Republic of Korea.
Ecotoxicol Environ Saf. 2021 Jan 1;207:111263. doi: 10.1016/j.ecoenv.2020.111263. Epub 2020 Sep 9.
Tris(2-chloroethyl) phosphate (TCEP) is an organophosphate flame retardant that used in textiles, industrial materials, and furniture to delay the spread of fire after ignition. TCEP has been detected in the tissues and eggs of fish and birds. However, there are no studies regarding the effects of TCEP on avian embryos. In the present study, we investigated the developmental toxicity of TCEP exposure on chicken embryos in a shell-less incubation system, which enables in situ observation. Chicken embryos were treated with graded doses of TCEP (50, 250, and 500 nmol/g egg) on incubation day 0. The survival rate, morphological biometrics, heart rate, and length and branch number of extraembryonic blood vessels were measured on incubation days 3-9. Survival rates were reduced from incubation day 3 and were significantly decreased until day 9. Body length, head + bill length and eye diameter were significantly reduced by TCEP exposure. Regarding skeletal effects, spine length was decreased in a dose-dependent manner on day 9. Body weight on day 9 significantly reduced in all TCEP treatment groups. These results suggest that TCEP exposure to >50 nmol/g egg retards development in chicken embryos. TCEP exposure to 500 nmol/g egg significantly increased heart weight to body weight ratio in the embryos. More than 250 nmol/g egg of TCEP significantly reduced the heart rate of embryos in the early developmental stage. The formation of extraembryonic blood vessels and the number of erythrocytes were significantly reduced even with 50 nmol/g egg of TCEP. These findings suggest that TCEP exposure specifically affects the cardiovascular system in chicken embryos, which leads to developmental delay. The results of this study also demonstrate that the shell-less incubation system can be used to continuously monitor the effects of chemicals on developing avian embryos.
三（2-氯乙基）磷酸酯（TCEP）是一种有机磷阻燃剂，用于纺织品、工业材料和家具中，以延缓点燃后的火势蔓延。TCEP 已在鱼类和鸟类的组织和卵中被检测到。然而，目前还没有关于 TCEP 对禽类胚胎影响的研究。在本研究中，我们在无壳孵化系统中研究了 TCEP 暴露对鸡胚胎的发育毒性，该系统能够进行原位观察。鸡胚胎在孵化第 0 天用不同剂量的 TCEP（50、250 和 500 nmol/g 卵）处理。在孵化第 3-9 天测量存活率、形态生物计量、心率以及胚胎外血管的长度和分支数。孵化第 3 天开始存活率降低，并一直持续到第 9 天显著降低。TCEP 暴露使体长、头+喙长和眼直径显著减小。关于骨骼效应，第 9 天脊柱长度呈剂量依赖性降低。所有 TCEP 处理组的第 9 天体重均显著降低。这些结果表明，TCEP 暴露量>50 nmol/g 卵会延迟鸡胚胎的发育。TCEP 暴露量为 500 nmol/g 卵时，胚胎的心脏重量与体重比显著增加。TCEP 超过 250 nmol/g 卵时，显著降低了胚胎在早期发育阶段的心率。即使暴露于 50 nmol/g 卵的 TCEP，胚胎外血管的形成和红细胞数量也显著减少。这些发现表明，TCEP 暴露特异性地影响鸡胚胎的心血管系统，导致发育延迟。本研究的结果还表明，无壳孵化系统可用于连续监测化学物质对禽类胚胎发育的影响。
