Die off, disease, mutation in wake of BP oil spill concern scientists

BP 435x292 Die off, disease, mutation in wake of BP oil spill concern scientistsThree years after BP’s Deepwater Horizon disaster unleashed the nation’s worst oil spill, a group of University of South Florida scientists have found evidence of a massive die-off at the base of the Gulf of Mexico’s food chain – a troubling sign that sea life in the area is far from returning to normal.

David Hollander, a USF chemical oceanographer, told the Tampa Bay Times that a die-off of tiny foraminifera stretches into the mile-deep DeSoto Canyon where BP’s Macondo well blew out in April 2010. From there the die-off emanates throughout the Gulf waters, following the trails forged by massive plumes of oil that lurked below the water’s surface for months.

“Everywhere the plume went, the die-off went,” Hollander told the Tampa Bay Times.

The discovery means the full impact of the oil spill on the Gulf’s ecological system has yet to be seen. As the Tampa Bay Times reports, “Although some pundits said the spill wasn’t as bad as everyone feared, further scientific research has found that corals in the gulf died,” while anglers reel in fish “with tattered fins and strange lesions” and dolphins continue to die in unusually high numbers.

The scientists have found that the dark oily sediment at the bottom of the Gulf contains the same chemical signature as the oil that blasted from BP’s Macondo well for 85 days in 2010. The same chemical signature has also been found in the livers of red snapper and other types of fish turning up with the same lesions. According to Hollander, fishes’ livers were trying to filter out impurities but couldn’t handle the enormous quantities of oil. Oil from the BP spill has also been connected to compromised immune systems and diseases in fish.

But while sick and diseased fish present a serious problem, it’s the possibility that the fish are being damaged at the genetic level that worries the scientists the most.

“If they get sick, that’s one thing,” USF fisheries biologist Steve Murawski told the Tampa Bay Times. “But if it changed their genes so that they’re less resistant to disease or have lower weights, that’s a big deal. That would be a real game-changer if true.”

Scientists are also finding the problem might not be so dire if BP hadn’t used record quantities (1.8 million gallons) of a chemical dispersant called Corexit, which is the reason why so much toxic sludge lies on the sea floor. As BP’s attempts to cap the out-of-control well failed, it began pumping the chemical directly at the well a mile below the surface.

Such an application of Corexit or any other type of oil dispersant was unprecedented.  As a result, the chemical broke down much of the oil into tiny particles that formed the giant suffocating plumes. Spring floods from the Mississippi River pushed a lot of the oil particles to the sea floor, where it formed a layer of sludge that scientists believe could remain in place for a century.

Although some of the effects of the Deepwater Horizon spill on the Gulf’s ecology are evident today, the truth is nobody knows how quickly, if ever, the Gulf will recover. Damage could take years to become apparent as it did with the Exxon Valdez spill in Alaska. There, eight years had passed before the herring population in Prince William Sound died off, ending a major food source and way of life for many of the area’s inhabitants.


Tampa Bay Times