After the infamous BP oil spill in 2010, where some of that oil ended up remained a mystery to scientists. Now, a new study from Florida State University has finally found where some of that missing oil wound up.
Some 200 million gallons of crude oil spilled into the Gulf of Mexico that day, and apparently since then 6 to 10 million gallons of it has been buried in the sediment on the Gulf floor - about 62 miles southeast of the Mississippi Delta.
And according to researchers, this news does not bode well for local marine life.
"This is going to affect the Gulf for years to come," lead author Jeff Chanton said in a statement. "Fish will likely ingest contaminants because worms ingest the sediment, and fish eat the worms. It's a conduit for contamination into the food web."
In addition, it has been shown that the spilled oil is linked to skin lesions in bottom-dwelling fish like the red snapper, and less speedy mahi-mahi. But fish aren't the only ones affected by these large oil slicks. Previous research has tied the ill-famed BP spill to unhealthy corals, a decline in Kemp's ridley sea turtles - a critically endangered species - and dolphins with hormone abnormalities.
And now it seems that the culprit is still at bay, with millions of gallons of oil still sitting in sediment on the sea floor.
In order to locate this remaining oil, Chanton and his colleagues used carbon 14, a radioactive isotope as an inverse tracer to determine where oil might have settled. Oil does not have carbon 14, so sediment that contained oil would immediately stand out. Then, they used geographic information system mapping to see where the oil-slicked sediment was scattered on the sea floor.
For some, it might appear that oil settling to the Gulf bottom would actually be beneficial in the short term, allowing the water to clear. However, Chanton says that it's a problem in the long run.
That's because there's less oxygen on the sea floor relative to the water column, so the oiled particles are more likely to become hypoxic - meaning they experience less oxygen. And when that happens, it becomes increasingly difficult for bacteria to break down the oil.
And even though some of this oil has now been found, researchers did not mention how scientists plan to clean it up. What's more, this is not even all of the missing oil from the BP spill. There's still many more gallons floating around out there, a looming threat to marine life.
The findings were published in the journal Environmental Science & Technology.
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