Abstract

The Hudson River (HR) Estuary has a long history of pollution with a variety of contaminants including PCBs and dioxins. In fact, 200 miles of the mainstem HR is designated a U.S. federal Superfund site, the largest in the nation, because of PCB contamination. The tidal HR hosts the southernmost spawning population of Atlantic tomcod, Microgadus tomcod, and studies revealed a correlation between exposure of juveniles to warm water temperature during summer to abundance of spawning adults of the same cohort in the following winter. Further, a battery of mechanistically linked biomarkers, ranging from the molecular to the population levels, were significantly impacted from contaminant exposures of the HR tomcod population. In response to xenobiotic insult, the HR tomcod population developed resistance to PCB and TCDD toxicity resulting from a deletion in the aryl hydrocarbon receptor2 (AHR2) gene. Furthermore, RNA-Seq analysis of global gene expression demonstrated that effects of the AHR2 polymorphism were far more pervasive than anticipated. The most highly PCB-contaminated sediments in the upper HR were dredged between 2009 and 2015 with the objective of lowering PCB concentrations in fishes in the lower HR. Success of the remediation project has been controversial. These observations suggest that tomcod provides an informative model to evaluate the efficacy of HR PCB remediation efforts on downriver fish populations and possible interactive effects between contaminant exposure and a warming environment.

 抽象的

哈德逊河 (HR) 河口长期以来受到多种污染物（包括多氯联苯和二恶英）的污染。事实上，由于 PCB 污染，HR 主干道 200 英里被指定为美国联邦超级基金站点，是全国最大的站点。潮汐HR是大西洋真鳕（ Microgadus tomcod ）最南端的产卵种群的栖息地，研究表明，夏季幼鱼暴露在温暖的水温下，与接下来的冬季同一群体产卵成体的丰度之间存在相关性。此外，HR tomcod 种群的污染物暴露对一系列从分子水平到种群水平的机械相关生物标志物产生了显着影响。为了应对异种生物的攻击，HR tomcod 群体对 PCB 和 TCDD 毒性产生了抵抗力，这是由于芳烃受体 2 (AHR2) 基因的缺失所致。此外，对全局基因表达的 RNA-Seq 分析表明，AHR2 多态性的影响比预期的更为普遍。 2009 年至 2015 年间，对 HR 上游 PCB 污染最严重的沉积物进行了疏浚，目的是降低 HR 下游鱼类中 PCB 的浓度。修复项目的成功一直存在争议。这些观察结果表明，tomcod 提供了一个信息丰富的模型来评估 HR PCB 修复工作对下游鱼类种群的有效性以及污染物暴露和环境变暖之间可能的相互作用影响。