The 2010 Deepwater Horizon (MC252) disaster in the northern Gulf of Mexico released more than 4 million barrels of crude oil. Oil rose from the ocean floor to the surface where many large pelagic fish spawn. Here we describe the impacts of field-collected oil samples on the rapidly developing embryos of warm-water predators, including bluefin and yellowfin tunas and an amberjack. For each species, environmentally relevant MC252 oil exposures caused serious defects in heart development. Moreover, abnormalities in cardiac function were highly consistent, indicating a broadly conserved developmental crude oil cardiotoxicity. Losses of early life stages were therefore likely for Gulf populations of tunas, amberjack, swordfish, billfish, and other large predators that spawned in oiled surface habitats.
深水地平线灾难在墨西哥湾北部泄漏了超过6.36亿升原油。原油泄漏污染了许多具有商业和生态意义的深海鱼类上层水域产卵栖息地。因此，金枪鱼，旗鱼等大型食肉动物发育中的卵（胚胎和幼虫）可能被暴露在原油衍生的多环芳香烃中（PAHs）。鱼类胚胎一般来说对PAH诱导的心脏中毒非常敏感，并且因此发生在心脏生理和形态的不利变化可能会引起急性滞后的死亡率。心脏功能对具有高有氧需求的快速游动的深海掠食者特别重要。这些物种的后代在相对较高温度下迅速发育，但他们面对原油毒性的脆弱性仍然未知。我们评估了现场采集的深水地平线（MC252）油样对包括蓝鳍金枪鱼，黄鳍金枪鱼和大头鱼在内的三种深海鱼类胚胎的影响。我们证明了实际环境暴露（1-15微克/升 总PAH）会导致所有三个品种表现为心包水肿和其他继发畸形中的循环受阻高潮的心脏功能特定剂量依赖性缺陷。每一个物种均显示出了暴露在原油泄漏下的不规则房性心律失常， 这表明了对原油毒性表现出的高度保守性反应。原油泄漏中收集的海湾水样有相当一部分的PAH浓度超过在此观察到的毒性阈值，这表明了深海鱼类幼虫损失的潜在可能性。对包括北极在内的其他海洋栖息地的脆弱性评估应着眼于作为对原油影响非常敏感和反应一致指标的当地鱼类种群心脏发育。
The Deepwater Horizon disaster released more than 636 million L of crude oil into the northern Gulf of Mexico. The spill oiled upper surface water spawning habitats for many commercially and ecologically important pelagic fish species. Consequently, the developing spawn (embryos and larvae) of tunas, swordfish, and other large predators were potentially exposed to crude oil-derived polycyclic aromatic hydrocarbons (PAHs). Fish embryos are generally very sensitive to PAH-induced cardiotoxicity, and adverse changes in heart physiology and morphology can cause both acute and delayed mortality. Cardiac function is particularly important for fast-swimming pelagic predators with high aerobic demand. Offspring for these species develop rapidly at relatively high temperatures, and their vulnerability to crude oil toxicity is unknown. We assessed the impacts of field-collected Deepwater Horizon (MC252) oil samples on embryos of three pelagic fish: bluefin tuna, yellowfin tuna, and an amberjack. We show that environmentally realistic exposures (1–15 µg/L total PAH) cause specific dose-dependent defects in cardiac function in all three species, with circulatory disruption culminating in pericardial edema and other secondary malformations. Each species displayed an irregular atrial arrhythmia following oil exposure, indicating a highly conserved response to oil toxicity. A considerable portion of Gulf water samples collected during the spill had PAH concentrations exceeding toxicity thresholds observed here, indicating the potential for losses of pelagic fish larvae. Vulnerability assessments in other ocean habitats, including the Arctic, should focus on the developing heart of resident fish species as an exceptionally sensitive and consistent indicator of crude oil impacts.