Yesterday marked the 10th anniversary of the BP Deepwater Horizon explosion that killed 11 workers and injured 17 others as the oil rig plunged 5,000 feet into the Gulf of Mexico. And for the next 87 days, 3.19 million barrels of oil (134 million gallons) spewed into the water, the worst offshore oil disaster in our history.
Oil damaged 1,300 miles of shoreline across the five states that border the Gulf, with the slick covering 43,300 square miles (the size of Virginia). For marine dealers in those states where fishing boats are their biggest sellers, the negative impact on boating, fishing and boat sales was devastating. And it wasn’t until six years later that BP was finally found responsible and ordered to pay more than $20.8 billion in civil and criminal penalties and natural resources penalties over a 15-year period that began in 2017.
So where are we today? NOAA is working with the public, educators and industry to support recovery of the Gulf’s natural resources using funds from the BP settlement. Among those is the University of South Florida’s College of Marine Science. In the decade since the disaster, USF researchers have circled the Gulf of Mexico, catching fish and cutting them open in search of toxic pollution. They recently reported sampling 2,503 fish representing 91 species from 359locations and multiple habitats around the Gulf, and found evidence of chronic oil pollution exposure in every one.
“We actually haven’t found one oil-free fish yet,” says Steven Murawski, the USF professor who has led the study, the most comprehensive analysis of oil pollution in fish of the Gulf everconducted. Popular recreational fish with the highest concentrations of the most toxic part of crude oil were yellowfin tuna, golden tilefish and red drum. Sought-after grouper and snapper also showed evidence of sustained PAH (polycyclic aromatic hydrocarbons) exposure but at lower levels than the top three.
Very important: People may wonder if this seafood OK to eat. Yes, say scientists, because it’s not near the level considered unsafe. But it raises serious questions about species’ long-term health, according to the USF study just published in Nature Scientific Reports.
Not surprising, the northern Gulf has the most extreme pollution “hot spots,” identified from samples obtained off the United States, Mexico and Cuba. But researchers are still trying to assess the full extent of the damage. For example, reports in a University of Miami-led study indicate the oil could have extended “in invisible but problematic concentrations, 30 percent farther than previously believed, nearer to west Florida and the Keys.”
Erin Pulster is the lead author of the USF study. Before the project, Pulster reports there was almost no research on oil’s effect on fish. The thinking, she says, had been that fish are adept at metabolizing toxins, so there was little worry about compounds accumulating in their bodies.
“Fish were largely ignored,” she says.
Pulster brings to light the concerns about repeated exposure and the long-term effects of bile that lingers in a fish’s system. To explain it, Murawski offers an excellent parallel with humans who metabolize alcohol after a night of drinking. A few cocktails will be cleared fairly quickly, but alcoholics might suffer cirrhosis and a failing liver over the long term. “If there’s repeated pollution events, the system in the liver breaks down, so at what point do chronic exposures really undermine the systems of the animal?”
Diminished productivity in such fish as red snapper, a prized recreational and commercial fish, is a major long-term fear. Fish are exposed to hydrocarbons in several ways. Bottom-feeders suck up crabs and other food where oil droplets adhering to dead plankton along with sediment from the Mississippi River all settled. But the sediment gets stirred up by storms — like a snow globe, Murawski says — so it’s back flying around in the water column where the fish can draw in toxins through their gills swimming through suspended oil droplets.
There is at least one good result of the Deepwater Horizon disaster, according to Murawski. It’san increased culture of safety in the oil industry, a product of some increased regulatory demands and, of course, nobody wanting to be the next Deepwater Horizon. “I don’t think we’re going to see an 87-day spill again,” he speculates.
That said, he does expect another well blowout sooner or later in because oil companies continue to drill in deeper areas. The companies consistently push for more areas and leases to be made available. For example, there’s a longstanding moratorium on drilling off Florida that will expire in 2022. While the Florida congressional delegation is already advocating for another 10-year extension, drilling operators are signaling their own desire by consistently going after leases closer to the moratorium line, essentially to the south and east of the Deepwater Horizon site.
Finally, scientists admit it’s nearly impossible to connect pollution in fish to a specific cause. Oil leaks into the Gulf from river runoff and other sources. However, oil pollution is highest in fish around the north central Gulf, with elevated levels following the Horizon disaster. Murawski estimates the discharge of oil after the rig sank was seven times greater than the annual leakage from natural seeps, and that elevation came in just 87 days.
For the boat dealers and marina operators surrounding the Gulf, saltwater recreational fishing is a cultural and economic mainstay. Recreational fishing generates billions of dollars annually in economic activity. Research like that at USF, and regulatory actions when appropriate, must continue to generate a healthy marine ecosystem. NOAA Fisheries is responsible for maintainingour sustainable and productive fisheries.
For the boating industry, it’s clearly in our best interest to advocate for needed research fundinggoing forward — perhaps now more than ever, as we can surely anticipate funding cuts and budget battles once an end to the covid-19 pandemic is finally in sight.