BP Oil Spill Dispersants Drifted, But Didn’t Degrade
Despite claims that chemical dispersants would help break down crude oil and eventually degrade in the water, a new study suggests that the spill hung around for months after the well was capped.
When the Deepwater Horizon exploded and sank in the Gulf of Mexico last April, it left an uncapped deepsea well that bled millions of gallons of oil into the ocean.
The study, which was published in Environmental Science & Technology, found that popular to contrary belief, the dispersant did not degrade but instead moved with the oil plumes until at least September, 2010.
Prior to the Gulf oil spill disaster, no deepwater applications of dispersant had been conducted, and thus no data existed on the environmental fate of dispersants in deepwater.
“When you read about Corexit, it’s supposed to biodegrade,” Carys Mitchelmore of the University of Maryland’s Center for Environmental Science told WiredScience. But specific rates have not generally been reported, she adds. So the dispersant’s apparent persistence in the new paper is somewhat unexpected.
Researchers like Mitchelmore admit that the jury’s still out on whether Corexit’s toxic cocktail of ingredients really act as a catalyst for oil degredation, or whether they actually make things worse.
As Care2′s Jasmine Greene reported recently, it’s not the lingering dispersant itself that could mean big problems for the environment and wildlife, it’s the mixture of Corexit and crude oil.
“The mix creates, poly-aromatic hydrocarbons (PAH), which has been identified as a carcinogen, mutagen and teratogen. The dispersant mixes with the oil and becomes water soluble, which then evaporates into the air. This harmful chemical comes down as rain in addition to being in the water on the beaches, soil, wetlands, even crab, oyster and mussel tissue.”
Image Credit: NOAA