Posts Tagged ‘polycyclic aromatic hydrocarbons’
Wednesday, March 21, 2012 @ 12:03 PM gHale
It has been almost two years since the April 20, 2010 explosion on the BP Deepwater Horizon drilling rig in the Gulf of Mexico and scientists are now getting a handle on the impact the disaster had on the environment.
For months, crude oil gushed into the water at a rate of 53,000 barrels per day before workers were able to cap the well July 15, 2010.
Oil from the Macondo well made it into the ocean’s food chain through the tiniest of organisms, zooplankton, a new study said.
Tiny drifting animals in the ocean, zooplankton are useful to track oil-derived pollution. They serve as food for baby fish and shrimp and act as conduits for the movement of oil contamination and pollutants into the food chain. The study confirms that not only did oil affect the ecosystem in the Gulf during the blowout, but it was still entering the food web after they capped the well.
Oil, which is a complex mixture of hydrocarbons and other chemicals, contains polycyclic aromatic hydrocarbons (PAHs), which can act as a fingerprint and determine its origin. Researchers were able to identify the signature unique to the Deepwater Horizon well in the Gulf of Mexico, where 11 workers perished in the April explosion.
“Our research helped to determine a ‘fingerprint’ of the Deepwater Horizon spill—something that other researchers interested the spill may be able to use,” said Dr. Siddhartha Mitra of East Carolina University. “Furthermore, our work demonstrated that zooplankton in the Northern Gulf of Mexico accumulated toxic compounds derived from the Macondo well.”
The team’s research indicates the fingerprint of the Deepwater Horizon oil spill was in some zooplankton in the Gulf of Mexico ecosystem at low levels, as much as a month after capping the leaking wellhead. In addition, the extent of the contamination seemed to be patchy. Some zooplankton at certain locations far removed from the spill showed evidence of contamination, whereas zooplankton in other locations, sometimes near the spill, showed lower indications of exposure to the oil-derived pollutants.
“Traces of oil in the zooplankton prove that they had contact with the oil and the likelihood that oil compounds may be working their way up the food chain,” said Dr. Michael Roman of the University of Maryland Center for Environmental Science.
The study was led by East Carolina University with researchers from the University of Maryland Center for Environmental Science, Oregon State University, Georgia Institute of Technology, and U.S. Geological Survey.