Gulf Of Mexico 52x More Toxic From Corexit Clean Up Than The Original Oil Spill Itself

Gulf Of Mexico 52x More Toxic From Corexit Clean Up Than The Original Oil Spill Itself

Friday, November 30, 2012 10:15

Study shows mixing oil with dispersant increased toxicity to Gulf’s ecosystems




Posted November 30, 2012 Atlanta, GA

If the 4.9 million barrels of oil that spilled into the Gulf of Mexico
during the 2010 Deep Water Horizon spill was a ecological disaster, the
two million gallons of dispersant used to clean it up apparently made it
even worse – 52-times more toxic. That’s according to new research from
the Georgia Institute of Technology and Universidad Autonoma de
Aguascalientes (UAA), Mexico.

The study found that mixing the dispersant with oil increased toxicity
of the mixture up to 52-fold over the oil alone. In toxicity tests in
the lab, the mixture’s effects increased mortality of rotifers, a
microscopic grazing animal at the base of the Gulf’s food web. The
findings are published online by the journal Environmental Pollution and will appear in the February 2013 print edition.

Using oil from the Deep Water Horizon spill and Corexit, the dispersant
required by the Environmental Protection Agency for clean up, the
researchers tested toxicity of oil, dispersant and mixtures on five
strains of rotifers. Rotifers have long been used by ecotoxicologists to
assess toxicity in marine waters because of their fast response time,
ease of use in tests and sensitivity to toxicants. In addition to
causing mortality in adult rotifers, as little as 2.6 percent of the
oil-dispersant mixture inhibited rotifer egg hatching by 50 percent.
Inhibition of rotifer egg hatching from the sediments is important
because these eggs hatch into rotifers each spring, reproduce in the
water column, and provide food for baby fish, shrimp and crabs in
estuaries.

“Dispersants are preapproved to help clean up oil spills and are widely
used during disasters,” said UAA’s Roberto-Rico Martinez, who led the
study. “But we have a poor understanding of their toxicity. Our study
indicates the increase in toxicity may have been greatly underestimated
following the Macondo well explosion.”

Martinez performed the research while he was a Fulbright Fellow at
Georgia Tech in the lab of School of Biology Professor Terry Snell. They
hope that the study will encourage more scientists to investigate how
oil and dispersants impact marine food webs and lead to improved
management of future oil spills.

“What remains to be determined is whether the benefits of dispersing
the oil by using Corexit are outweighed by the substantial increase in
toxicity of the mixture,” said Snell, chair of the School of Biology.
“Perhaps we should allow the oil to naturally disperse. It might take
longer, but it would have less toxic impact on marine ecosystems.”


Source:-
http://beforeitsnews.com/environment/2012/11/gulf-of-mexico-52x-more-toxic-from-the-corexit-clean-up-than-the-original-oil-spill-itself-2455448.html