Apr 22, 2020 8:00 AM

The Deepwater Horizon Disaster Fueled a Gulf Science Bonanza

A decade after the worst oil spill in US history, researchers have turned out a massive data set charting the health of the ecosystem.

After the Deepwater Horizon drilling rig exploded a decade ago this month, killing 11 workers and spewing a massive black curtain of crude oil across the Gulf of Mexico, thousands of first responders and cleanup workers arrived on the scene. So too did an army of scientists. Aboard seagoing research vessels and wading along beaches and marshes, they came to assess the catastrophe and track it over time. British Petroleum, owner of the rig, agreed to fund a scientific stimulus package of $500 million just a few weeks after the April 20, 2010, blowout.

The 134 million gallons of oil devastated wildlife from Texas to Florida, killing thousands of marine mammals, such as dolphins and sea turtles, according to federal officials, and destroying shoreline and underwater habitats for commercially important fish, crabs, shrimp, and oysters. More than 25,000 fishermen and seafood industry workers were suddenly out of work, with a 10-year price tag of $4.5 billion in total economic losses, according to a 2019 study by a trio of researchers funded in part by the National Oceanic and Atmospheric Administration.

At the same time, BP’s payout was a boon for scientific research. It led to a deeper understanding of the gulf’s ecosystem—its marine life and its physical systems—and how to preserve it. It also led to new scientific tools and models that are helping researchers assess environmental damage around the world. That pile of money—spread out over 10 years—funded hundreds of grants under the umbrella of the Gulf of Mexico Research Initiative, or GoMRI, an independent scientific advisory panel that awarded grants based on merit reviews by scientific peers.

Studies ranged from developing an algorithm to predict oil slicks when satellite images aren’t available, to a way of using fiddler crabs and snails to monitor the health of Louisiana salt marshes. Other studies detailed the physical oceanography, biology, and marine chemistry of the Deepwater Horizon spill’s impact zone, as well as its economic and psychological effects on coastal fishing communities.

Starting in 2011, the BP money also funded the data collection efforts of people like Chris Reddy, a senior scientist at the Woods Hole Oceanographic Institution. Reddy is an expert in oil spill science who in 2010 helped determine the size, heading, and chemical composition of the underwater plume from an oceanographic research vessel and underwater robot near the Macondo well site, about 80 miles south of New Orleans. In 2012, a federal judge ruled that Reddy and another scientist had to turn over internal emails (and much more, including raw data from instruments and processed data) about their scientific research to BP, which was preparing a defense against a federal lawsuit over the spill. Reddy’s research helped determine that the flow rate was much larger than BP or federal officials originally estimated; initially it was estimated to only be about 40,000 to 200,000 gallons per day. But the work of Reddy and fellow Woods Hole scientist Rich Camilli showed it was actually up to 2.8 million gallons per day.

Reddy’s data also supported a 2015 settlement in which BP officials agreed to plead guilty to 14 criminal charges arising over the spill and to pay $20 billion in damages to the Department of Justice, as well as $4.5 billion to the five coastal states. “If you are looking for a legacy, it may not be a published paper, but the data set that was behind it,” says Reddy. “It’s a gold mine and it’s going to continue to be tapped.”

Reddy received funding from GoMRI starting a year before his legal fight with BP, and that funding continued until 2018. At the time, he and other scientists feared BP’s legal maneuvers would have a chilling effect on the ability of researchers to study the gulf without pressure. It also took a considerable toll on his spirits, Reddy recalls, to fight a court battle while conducting research.

Today, Reddy has changed his tune a bit. He says that the initial shot of BP research money made a difference for him and other scientists who were trying to understand what happened. He says marine scientists and oil industry engineers had to learn to get along to figure out how to stop the oil, and how to measure where it was headed. “We live in this ivory tower,” Reddy adds, “and suddenly we crashed a party with a wide range of guests. We didn’t know the language, the customs, and the dress code. It was difficult and challenging, and there were some clashes. Ten years later, there’s a much better working relationship with the oil spill science community.”

The BP money that set up GoMRI also led to the deployment by microbiologists from several labs of new genetic tests on naturally occurring bacteria and plankton around the oil spill and on Gulf coast beaches and marshes. These tests were able to prove whether an area had been hit by the oil spill, even if much of the oil itself had evaporated, or become buried in bottom sediments.

“One of the issues we were dealing with is how to track the oil,” says Samantha Joye, a marine scientist at the University of Georgia. Joye says these genetic tests used by her lab and others allowed researchers to track microbial populations. They found new species of bacteria that consume oil at various water depths and conditions, and discovered that chemical dispersants that federal officials used to fight the spill were killing these natural oil-eating bacteria.

Joye adds the Deepwater Horizon spill was the first time that microbiologists had the tools, methods, and funding to use this technique to accurately measure ecological damage. While oily seabirds and dying dolphins usually grab the media spotlight during a spill, she notes that changes at the bottom of the food chain are perhaps more important to document. “You can put an assessment on how many square miles of beach were damaged, but how do you come up with a price tag on plankton?” Joye asks. “They are the biological engine of the system. Without those organisms, the entire ecosystem collapses.”

Joye led a committee of microbiologists studying the Deepwater Horizon spill, which published an overview of these findings in March.

Nearly all of the research studies from the initial $500 million of GoMRI funds have been completed; one of the largest examined the effects of oil on 91 fish species in the Gulf of Mexico. From 2011 to 2018, researchers from the University of South Florida and several other institutions sampled more than 2,500 individual fish and found evidence of oil exposure in all of them, as they reported last week in the journal Nature Scientific Reports.

“We actually haven’t found one oil-free fish yet,” says Steven Murawski, the USF professor of marine science who led the $37 million research effort. Yellowfin tuna, golden tilefish, and red drum had the highest concentrations of polycyclic aromatic hydrocarbons (known as PAHs, which are the most toxic part of crude oil), while commercially important grouper and red snapper had slightly lower levels.

Murawski says that while the fish aren’t dying of direct exposure from PAHs, the toxins are accumulating in their livers—making them less healthy and as a result, more susceptible to disease or parasites. He believes that there is a tipping point of continuous exposure to oil, past which some species will be wiped out. Biologists like Murawski say they hope they can find this point before it's too late.

Erin Pulster, a scientific researcher at USF, was an author on the new study. She says she was surprised that oil was still accumulating so many fish species. “I blindly assumed the pollution levels would decrease,” Pulster points out. “The fact they are increasing over time surprised me.”

Pulster says the contamination is the result of spilled oil from Deepwater Horizon that has settled on the seafloor, but which is then kicked up again into the water column by passing tropical storms. More oil and contaminants continue to flow from farms, factories, and cities along the Mississippi River into the gulf, which also absorbs constant leaks from the thousands of oil and gas operations.

Looking back, the scientists who responded to the Deepwater Horizon spill say that the past decade has brought a bonanza of new research. “It was a horrible tragedy and 11 men died,” the University of Georgia's Joye says. “But the scientific community rose to the challenge and we learned a tremendous amount from that disaster.”

Despite the toxic contamination she found during years of dissecting fish guts, Pulster says she still prefers locally caught seafood. “I eat gulf fish, oysters, and shrimp,” she admits. “They are too good not to eat. But I wouldn’t eat the liver.”