That's great news...the dispersant was meant to prevent the damage caused by oil. Clearly the off-shore drilling industry is stabbing in the dark when they present their risk assessments to regulators.
Though perhaps the dispersant served another purpose...BP still faces potential fines from the civil charges that can cost anywhere between $1100 to $4300 per barrel that spilled. The dispersant could have made the total amount more difficult to assess.
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.
Gulf of Mexico clean-up makes 2010 spill 52-times more toxic; Mixing oil with dispersant increased toxicity to ecosystemsUsing 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.
Though perhaps the dispersant served another purpose...BP still faces potential fines from the civil charges that can cost anywhere between $1100 to $4300 per barrel that spilled. The dispersant could have made the total amount more difficult to assess.
