Several naturally occurring dioxins, including 1,3,7-tribromodibenzo-p-dioxin (1,3,7-TriBDD), synthesized by red algae, have been detected in the marine environment. As 1,3,7-TriBDD is accumulated in mussels and fish, predators, such as marine birds, are exposed to this congener, similar to anthropogenic dioxins (including 2,3,7,8-tetrachlorodibenzo-p-dioxin TCDD). However, little is known about the impact of 1,3,7-TriBDD exposure on the bird health. To understand the effects of 1,3,7-TriBDD on birds, the phenotypic effects and hepatic transcriptome were investigated in chicken (Gallus gallus) embryos treated with 27 μM (2.9 ng/g egg) and 137 μM (14.4 ng/g egg) 1,3,7-TriBDD. The blood glucose levels in the 1,3,7-TriBDD-treated groups were lower than those in the control group. The transcriptome analysis of 6520 sequences in the 27 and 137 μM 1,3,7-TriBDD-treated groups identified 733 and 596 differentially expressed genes (DEGs). Cytochrome P450 1A4 and 1A5 were also identified as DEGs, suggesting that the aryl hydrocarbon receptor is activated by this congener. Pathway and network analyses with DEGs suggested that 1,3,7-TriBDD may induce carcinogenic effects and metabolic alterations. These results were similar to the effects on TCDD-treated embryos. Nevertheless, the overall transcriptome results suggested that compared with TCDD, 1,3,7-TriBDD has a unique impact on insulin- and peroxisome-signaling pathways in chicken embryos. Differences in altered transcriptome profiles between 1,3,7-TriBDD- and TCDD-treated embryos may lead to different phenotypic effects: less severe effects of 1,3,7-TriBDD and more fatal effects of TCDD. Collectively, these findings warrant the further assessment of the hazard and risk of 1,3,7-TriBDD on marine animals, considering increased exposure due to climate change.

在海洋环境中已检测到几种天然存在的二恶英，包括由红藻合成的 1,3,7-三溴二苯并对二恶英 (1,3,7-TriBDD)。由于 1,3,7-TriBDD 在贻贝和鱼类中积累，海鸟等捕食者会接触到这种同系物，类似于人为二恶英（包括 2,3,7,8-四氯二苯并-对二恶英 TCDD）。然而，关于 1,3,7-TriBDD 暴露对鸟类健康的影响知之甚少。为了解 1,3,7-TriBDD 对鸟类的影响，研究了鸡 ( Gallus gallus ) 的表型效应和肝脏转录组) 用 27 μM（2.9 ng/g 鸡蛋）和 137 μM（14.4 ng/g 鸡蛋）1,3,7-TriBDD 处理的胚胎。1,3,7-TriBDD治疗组的血糖水平低于对照组。对 27 和 137 μM 1,3,7-TriBDD 处理组中 6520 个序列的转录组分析鉴定了 733 个和 596 个差异表达基因 (DEG)。细胞色素 P450 1A4 和 1A5 也被鉴定为 DEG，表明芳烃受体被该同源物激活。DEGs 的通路和网络分析表明 1,3,7-TriBDD 可能诱导致癌作用和代谢改变。这些结果与对 TCDD 处理的胚胎的影响相似。尽管如此，整体转录组结果表明，与 TCDD 相比，1,3,7-TriBDD 对鸡胚胎中的胰岛素和过氧化物酶体信号通路具有独特的影响。1,3,7-TriBDD 和 TCDD 处理的胚胎之间转录组谱改变的差异可能导致不同的表型效应：1,3,7-TriBDD 的严重影响和 TCDD 的更致命影响。总的来说，考虑到气候变化导致的暴露增加，这些发现值得进一步评估 1,3,7-TriBDD 对海洋动物的危害和风险。