研究表明，2010年发生的灾难性深水地平线(DWH)漏油事件，可能比之前认为的严重得多，原因是“看不见的有毒”石油。
这次泄漏是海洋历史上最大的一次，向墨西哥湾释放了大约7.95亿升(2.1亿加仑)的石油，油膜覆盖了大约57500平方英里的区域。这场灾难造成了大范围的环境破坏，并迫使墨西哥湾的大片区域停止捕鱼作业。
通常，科学家主要使用卫星来跟踪像这样的重大漏油事件，然而，这种技术不一定能揭示环境问题的全部。
根据发表在杂志上的一项研究科学进步，泄漏的“有毒范围”可能比先前卫星数据显示的要大30%，留下的足迹从佛罗里达的墨西哥湾延伸到德克萨斯和佛罗里达群岛的海岸。
“虽然深水地平线号漏油事件已经得到了广泛的研究，但几个基本问题仍然没有答案:DWH漏油事件的全部范围是什么？卫星足迹能解释整个漏油范围吗？泄漏的一部分是否超出了卫星覆盖范围，但对海洋动物仍然有毒？”这项研究的作者是迈阿密大学的伊加尔·贝伦斯坦和克莱尔·帕里斯新闻周刊。
他们说:“这些基本问题对于我们理解深水地平线号漏油事件，尤其是海洋漏油事件非常重要。”。
在这项研究中，除了卫星图像和墨西哥湾石油流动模型之外，科学家们还检查了此前公布的其他小组在漏油现场进行的现场测量。
他们的分析显示，在卫星确定的泄漏区域的假定边界之外，墨西哥湾或墨西哥的大部分地区暴露在对海洋生物有毒的“隐形”石油中。
“我们发现石油泄漏超出了卫星覆盖范围，到达了被认为未受污染的地区，如西佛罗里达大陆架和德克萨斯海岸。超出卫星足迹的一部分不可见部分对海洋生物是有毒的，”作者说。
根据这项研究，被称为多环芳烃的有毒化学物质可能在卫星无法探测到浮油后的几天甚至几周内仍然存在于水中。
2010年7月3日，在路易斯安那州海岸附近的墨西哥湾，在深水地平线泄漏点附近可以看到支持船。
“由于这项研究，我们现在知道有毒浓度的石油可以延伸到卫星足迹之外，并可以在泄漏不再可见后继续存在于水中，”作者说。
“我们提供了一个定量框架来计算这些石油浓度及其在时间和空间上的范围，以便更好地说明石油泄漏对海洋生态系统的影响。我们表明，环境损害远远超出了以前在空间和时间上的估计。”
研究人员表示，他们在研究中使用的分析可以应用于未来的石油泄漏，以便更好地评估其影响。
“我们推荐这种方法作为卫星估算的补充，”贝伦斯坦·巴黎在一份声明中说。“目前，卫星能够最快速、最准确地显示浮油的位置。但漏油还会延伸到水柱中，在那里水流与上层环流分离。
作者表示，鉴于世界范围内与石油生产相关的活动正在增加，最新的发现可能具有重大意义。
“漏油是全球范围内非常频繁的事件。总的来说，关于石油泄漏的概念是，石油在可见的地方是危险的，”作者告诉新闻周刊。“几乎没有关于石油中看不见但仍然有毒的部分的说明。我们提出并量化了DWH有毒和不可见石油的概念，并强调在评估未来石油泄漏的损害和/或风险时应考虑到这一部分。”
2010年4月20日，位于路易斯安那州海岸41英里处的英国石油公司运营的深水地平线钻井平台发生爆炸，导致11名工人死亡，造成了深水泄漏。
据报道，钻井平台随后沉没，在87天的时间里，超过400万桶石油从受损的马孔多油井中涌出，直到漏油最终被堵住环境保护局。
此次泄漏是美国历史上最严重的环境灾难之一，严重破坏了墨西哥湾的生态系统和地区经济，同时也损害了该地区许多居民的健康。
2014年，一名美国联邦法官裁定，英国石油公司在操作钻井平台时表现出严重疏忽，对漏油事件负有主要责任。一年后，这家英国公司同意向美国政府和五个州支付价值约187亿美元的罚款。据路透社报道，这是美国历史上最大的企业和解。
'INVISIBLE AND TOXIC' OIL FROM DEEPWATER HORIZON SPILL MAY HAVE MADE DISASTER MUCH WORSE THAN PREVIOUSLY THOUGHT
The catastrophic Deepwater Horizon (DWH) oil spill, which occurred in 2010, may have been significantly worse than previously thought due to "invisible and toxic" oil, research suggests.
The spill was the largest in marine history, releasing around 795 million liters (210 million gallons) of oil into the Gulf of Mexico with slicks covering an estimated area of 57,500 square miles. The disaster caused extensive environmental damage and forced the closure of vast stretches of the Gulf to fishing operations.
Normally, scientists primarily use satellites to track major oil spills such as these, however, this technique does not necessarily reveal the full extent of the environmental problem.
According to a study published in the journal Science Advances, the "toxic extent" of the spill could have been up to 30 percent greater than what previous satellite data has suggested, leaving a footprint which stretched from Florida's Gulf Coast, to the shores of Texas and the Florida Keys.
"While the Deepwater Horizon oil spill has been extensively studied, several fundamental questions remained unanswered: What was the full extent of the DWH oil spill? Does the satellite footprint account for the entire oil spill extent? And is there a part of the spill that extends beyond the satellite footprint but is still toxic to marine animals?" the authors of the study Igal Berenshtein and Claire Paris from the University of Miami, told Newsweek.
"These fundamental questions are highly important for our understanding of the Deepwater Horizon oil spill in particular, and marine oil spills in general," they said.
For the study, the scientists examined previously published on-site measurements taken by other teams at the spill site, in addition to satellite imagery and models of oil movement in the Gulf.
Their analysis revealed that large areas of the Gulf or Mexico beyond the assumed boundary of the spill area determined by satellites were exposed to "invisible" oil that was toxic to marine organisms.
"We found that the oil spill extended beyond the satellite footprint, reaching areas which were considered non-contaminated such as the West Florida shelf and Texas shores. A part of the invisible portion that extended beyond the satellite footprint was toxic to marine life," the authors said.
According to the study, toxic chemicals known as polycyclic aromatic hydrocarbons may still be present in water for days or even weeks after satellites can no longer detect an oil slick.
Support ships are seen near the Deepwater Horizon spill site on July 3, 2010 in the Gulf of Mexico off the coast of Louisiana.
"Thanks to this study we now know that toxic concentrations of oil can extend beyond the satellite footprint, and can persist in the water after the spill is no longer visible," the authors said.
"We provide a quantitative framework to compute these oil concentrations and their extent in time and space, to better account for the impact of oil spills on the marine ecosystem. We show that the environmental damage extends substantially beyond what was previously estimated both in space and time."
The researchers say that the analysis they used in the study could be applied to future oil spills in order to better assess their impacts.
"We recommend this method as complementary to satellite estimates," Berenshtein Paris said in a statement. "Currently, satellites provide the most rapid and accurate indication of the locations of the oil slicks. But the oil spill also extends in the water column where currents are decoupled from the upper circulation."
The authors say the latest findings could have significant implications given that activities related to petroleum production are increasing around the world.
"Oil spills are highly frequent events worldwide. In the general, the conception regarding oil spills is that oil is hazardous where it is visible," the authors told Newsweek. "There is nearly no accounting for the portions of the oil that are invisible but are still toxic. We bring forward and quantify the concept of the DWH toxic and invisible oil, and stress that this portion should be accounted for when assessing damage and/or risk of future oil spills."
The Deepwater spill was caused by an explosion on the BP-operated Deepwater Horizon oil drilling rig—located around 41 miles off the Louisiana coast—on April 20, 2010, which resulted in the deaths of 11 workers.
The rig subsequently sank and more than four million barrels of oil gushed out of the damaged Macondo well over the course of 87 days until the leak was finally capped, according to the Environmental Protection Agency.
The spill was one of the worst environmental disasters in American history, severely damaging the Gulf of Mexico ecosystem and the regional economy, while also harming the health of many residents in the region.
In 2014, a U.S. federal judge ruled that BP had displayed gross negligence in its operation of the rig and was primarily responsible for the spill. A year later, the British company agreed to pay fines worth around $18.7 billion to the U.S. government and five states. This is the largest corporate settlement in American history, Reuters reported.
