10 years after US oil spill…Scientists find oil & chemicals in 91 species of fish; US$71B spent on clean up; Guyana is still to have full insurance

May 31, 2021 News

---

Kaieteur News – A decade after BP and its partners spent US$71B to clean up the catastrophic 2010 oil spill at the Deepwater Horizon rig in the Gulf of Mexico, a study was conducted by marine scientists with the University of South Florida (UFS) to ascertain the effect of the spill on the marine life in the area.
The scientists sampled more than 2,500 individual fish representing 91 species from 359 locations across the Gulf of Mexico. Interestingly, their study found evidence of oil exposure in all of them, including some of the most popular types of seafood. According to the study done in 2020, the highest levels were detected in yellowfin tuna, golden tilefish and red drum.
The study that was published in “Nature Scientific Reports,” represents the first comprehensive, Gulf-wide survey of oil pollution launched in response to the Deepwater Horizon spill. It was funded by a nearly US$37 million grant from the independent Gulf of Mexico Research Initiative (GoMRI) to establish the Center for Integrated Modeling and Analysis of Gulf Ecosystems (C-IMAGE), an international consortium of professors, post-doctoral scholars and students from 19 collaborating institutions.
Over the last decade, USF scientists conducted a dozen research expeditions to locations off the United States, Mexico and Cuba examining levels of polycyclic aromatic hydrocarbons (PAHs), the most toxic chemical component of crude oil, in the bile of the fish. Bile is produced by the liver to aid in digestion, but it also acts as storage for waste products.
“We were quite surprised that among the most contaminated species was the fast-swimming yellowfin tuna as they are not found at the bottom of the ocean where most oil pollution in the Gulf occurs,” said lead author Erin Pulster, a researcher in USF’s College of Marine Science. “Although water concentrations of PAHs can vary considerably, they are generally found at trace levels or below detection limits in the water column. So where is the oil pollution we detected in tunas coming from?”

Pulster says it makes sense that tilefish have higher concentrations of PAH because they live their entire adult lives in and around burrows that they excavate on the seafloor and PAHs are routinely found in Gulf sediment. However, their exposure has been increasing over time, as well as in other species, including groupers, some of Florida’s most economically important fish. In a separate USF-led study, her team measured the concentration of PAHs in the liver tissue and bile of 10 popular grouper species. The yellowedge grouper had a concentration that increased more than 800 percent from 2011 to 2017.
Fish with the highest concentrations of PAH were found in the northern Gulf of Mexico, a region of increased oil and gas activity and in the vicinity of the Deepwater Horizon spill that gushed nearly four million barrels of oil over the course of three months in 2010. Oil-rich sediments at the bottom where much of the oil settled are resuspended by storms and currents, re-exposing bottom-dwelling fish.
Oil pollution hot spots were also found off major population centers, such as Tampa Bay, suggesting that runoff from urbanized coasts may play a role in the higher concentrations of PAHs. Other sources include chronic low-level releases from oil and gas platforms, fuel from boats and airplanes and even natural oil seeps—fractures on the seafloor that can ooze the equivalent of millions of barrels of oil per year.
“This was the first baseline study of its kind, and it’s shocking that we haven’t done this before given the economic value of fisheries and petroleum extraction in the Gulf of Mexico,” said Steven Murawksi, professor of fisheries biology at USF, who led the international research effort.
Despite the detected trends of oil contamination in fish bile and liver, fish from the Gulf of Mexico are tested rigorously for contaminants to ensure public safety and are safe to eat because oil contaminants in fish flesh are well below public health advisory levels. Chronic PAH exposure, however, can prevent the liver from functioning properly, resulting in the decline of overall fish health.
These studies were made possible by BP’s 10-year, $500 million commitment to fund independent research on the long-term effects of the Deepwater Horizon spill administered by the Gulf of Mexico Research Initiative. This year marks the end of that funding.
“Long-term monitoring studies such as these are important for early warning of oil pollution leaks and are vital for determining impacts to the environment in the case of future oil spills,” Pulster said. (Source: https://www.usf.edu/news/2020/first-gulf-of-mexico-wide-survey-of-oil-pollution-in-fish-completed-10-years-after-deepwater-horizon.aspx)
THE DEEPWATER HORIZON SPILL
Deepwater Horizon oil spill, also called Gulf of Mexico oil spill, is considered one of the largest marine oil spills in history, caused by an April 20, 2010, explosion on the Deepwater Horizon oil rig—that was located in the Gulf of Mexico, approximately 41 miles (66 km) off the coast of Louisiana—and its subsequent sinking on April 22.
The Deepwater Horizon rig, owned and operated by offshore-oil-drilling company Transocean and leased by oil company BP, was situated in the Macondo oil prospect in the Mississippi Canyon, a valley in the continental shelf.
On the night of April 20, a surge of natural gas blasted through a concrete core recently installed by contractor Halliburton in order to seal the well for later use. It later emerged through documents released by Wikileaks that a similar incident had occurred on a BP-owned rig in the Caspian Sea in September 2008. Both cores were likely too weak to withstand the pressure because they were composed of a concrete mixture that used nitrogen gas to accelerate curing.
Once released by the fracture of the core, the natural gas traveled up the Deepwater rig’s riser to the platform, where it ignited, killing 11 workers and injuring 17. The rig capsized and sank on the morning of April 22, rupturing the riser, through which drilling mud had been injected in order to counteract the upward pressure of oil and natural gas. Without any opposing force, oil began to discharge into the gulf. The volume of oil escaping the damaged well—originally estimated by BP to be about 1,000 barrels per day—was thought by U.S. government officials to have peaked at more than 60,000 barrels per day. The total estimated volume of leaked oil approximated with plus or minus 10% uncertainty, including oil that was collected, making it the world’s largest accidental spill.
CLEANUP EFFORTS
The petroleum that had leaked from the well before it was sealed formed a slick extending over more than 57,500 square miles (149,000 square km) of the Gulf of Mexico. To clean oil from the open water, 1.8 million gallons of dispersants—substances that emulsified the oil, thus allowing for easier metabolism by bacteria—were pumped directly into the leak and applied aerially to the slick. Booms to corral portions of the slick were deployed, and the contained oil was then siphoned off or burned. As oil began to contaminate Louisiana beaches in May, it was manually removed; more difficult to clean were the state’s marshes and estuaries, where the topography was knit together by delicate plant life. By June, oil and tar balls had made landfall on the beaches of Mississippi, Alabama, and Florida. In all, an estimated 1,100 miles (1,770 km) of shoreline were polluted.
AFTERMATH AND IMPACT
Economic prospects in the Gulf Coast states were dire, as the spill affected many of the industries upon which residents depended. More than a third of federal waters in the gulf were closed to fishing at the peak of the spill, due to fears of contamination. A moratorium on offshore drilling, enacted by former U.S. Pres. Barack Obama’s administration despite a district court reversal, left an estimated 8,000–12,000 temporarily unemployed. Few travelers were willing to face the prospect of petroleum-sullied beaches, leaving those dependent on tourism struggling to supplement their incomes. Following demands by Obama, BP created a US$20 billion compensation fund for those affected by the spill. A year later nearly a third of the fund had been paid out, though lack of oversight allowed government entities to submit wildly inflated claims, some unrelated to the spill. By 2013, the fund was largely depleted.
Numerous investigations explored the causes of the explosion and record-setting spill. The U.S. Government report, published in September 2011, pointed to defective cement on the well, faulting mostly BP, but also rig operator Transocean and contractor Halliburton. Earlier in 2011, a White House commission likewise blamed BP and its partners for a series of cost cutting decisions and an inadequate safety system, but also concluded that the spill resulted from “systemic” root causes and “absent significant reform in both industry practices and government policies, might well recur.”
CONCERNS FOR GUYANA
The findings by the marine scientists have also caught the attention of local industry experts who related to Kaieteur News that they should serve as a wake up call for Guyana which is pursing massive oil projects in the Stabroek Block without full coverage insurance. This newspaper has reported on several occasions that Guyana is yet to receive official documentation or any piece of evidence for that matter to say that ExxonMobil would stand the costs for clean up and restoration programmes, following any oil spill from the Liza Phase One, Liza Phase Two, and Payara projects.
In the absence of full coverage insurance, stakeholders have expressed deep concern about the billions of dollars in expenses Guyana would be left with following any irreparable damage that follows from an oil spill.
What has also left stakeholders in a deep state of worry is the fact that Guyana has no independent study on the potential harmful effects on its marine life from an oil spill. There is also no provision in the Production Sharing Agreement for the Stabroek Block which ensures ExxonMobil would undertake to do such a study and provide compensation should Guyana be affected in this way.

 

---

---