EPA Required Dispersant For BP Oil Spill Clean-Up Increased Toxicity 52 Fold: The EPA Cure Is Worse Than The Spill And Worse Than Letting Nature Clean-Up The Oil

From "Worse Than the Problem: Clean-up Makes 2010 Spill 52x More Toxic" on ScienceBlog:

The study [from the Georgia Institute of Technology and Universidad Autonoma de Aguascalientes (UAA), Mexico] 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. [Emphasis added.]

Terry Snell, chair of the Georgia Institute of Technology School of Biology said, "Perhaps we should allow the oil to naturally disperse. It might take longer, but it would have less toxic impact on marine ecosystems."