Abstract：
Alaska contains over 600 formerly used defense (FUD) sites, many of which serve as point sources of pollution. These sites are often co-located with rural communities that depend upon traditional subsistence foods, especially lipid-rich animals that bioaccumulate and biomagnify persistent organic pollutants (POPs). Many POPs are carcinogenic and endocrine-disrupting compounds that are associated with adverse health outcomes. Therefore, elevated exposure to POPs from point sources of pollution may contribute to disproportionate incidence of disease in arctic communities. We investigated PCB concentrations and the health implications of POP exposure in sentinel fishes collected near the Northeast Cape FUD site on Sivuqaq (St. Lawrence Island), Alaska. Sivuqaq residents are almost exclusively Yupik and rely on subsistence foods. At the request of the Sivuqaq community, we examined differential gene expression and developmental pathologies associated with exposure to POPs originating at the Northeast Cape FUD site. We found significantly higher levels of PCBs in Alaska blackfish (Dallia pectoralis) collected from contaminated sites downstream of the FUD site compared to fish collected from upstream reference sites. We compared transcriptomic profiles and histopathologies of these same blackfish. Blackfish from contaminated sites overexpressed genes involved in ribosomal and FoxO signaling pathways compared to blackfish from reference sites. Contaminated blackfish also had significantly fewer thyroid follicles and smaller pigmented macrophage aggregates. Conversely, we found that ninespine stickleback (Pungitius pungitius) from contaminated sites exhibited thyroid follicle hyperplasia. Despite our previous research reporting transcriptomic and endocrine differences in stickleback from contaminated vs. reference sites, we did not find significant differences in kidney or gonadal histomorphologies. Our results demonstrate that contaminants from the Northeast Cape FUD site are associated with altered gene expression and thyroid development in native fishes. These results are consistent with our prior work demonstrating disruption of the thyroid hormone axis in Sivuqaq residents.
摘要：
阿拉斯加包含600多个以前使用过的防御（FUD）站点，其中许多是点污染源。这些地点通常与依赖传统生计食品的农村社区位于同一地点，尤其是生物积累和生物放大持久性有机污染物（POPs）的富含脂质的动物。许多持久性有机污染物是致癌和内分泌干扰化合物，与不良健康结果有关。因此,来自点污染源的持久性有机污染物暴露量增加可能导致北极社区疾病发生率不成比例。我们调查了在Sivuqaq（圣劳伦斯岛）东北角FUD站点附近收集的前哨鱼类中的PCB浓度和POP暴露对健康的影响，阿拉斯加Sivuqaq居民几乎完全是Yupik，并依靠生计食品。应Sivuqaq社区的要求，我们研究了与暴露于东北开普FUD位点的POPs相关的差异基因表达和发育病理。我们发现，与从上游参考站点收集的鱼相比，从FUD站点下游污染站点收集的阿拉斯加黑鱼（Dalliapectoralis）中的多氯联苯含量明显更高。我们比较了这些相同黑鱼的转录组谱和组织病理学。与参考位点的黑鱼相比，来自污染位点的黑鱼过表达了参与核糖体和FoxO信号通路的基因。受污染的黑鱼的甲状腺滤泡也明显较少，色素巨噬细胞聚集体较小。相反，我们发现，来自污染部位的九分之一粘附分子（Pugitiuspungitius）表现出甲状腺滤泡增生。尽管我们以前的研究报告了受污染的棘鱼的转录组和内分泌差异参考网站，我们没有发现肾脏或性腺组织形态的显著差异.我们的结果表明，东北开普FUD位点的污染物与本地鱼类的基因表达改变和甲状腺发育有关。这些结果与我们先前的工作一致，表明Sivuqaq居民中甲状腺激素轴的破坏。
