“Corexit 9527, considered by the EPA to be an acute health hazard, is stated by its manufacturer to be potentially harmful to red blood cells, the kidneys and the liver, and may irritate eyes and skin. The chemical 2-butoxyethanol, found in Corexit 9527, was identified as having caused lasting health problems in workers involved in the cleanup of the Exxon Valdez oil spill. According to the Alaska Community Action on Toxics, the use of Corexit during the Exxon Valdez oil spill caused people “respiratory, nervous system, liver, kidney and blood disorders”. Like 9527, 9500 can cause hemolysis (rupture of blood cells) and may also cause internal bleeding.

According to the EPA, Corexit is more toxic than dispersants made by several competitors and less effective in handling southern Louisiana crude.
On May 20, 2010, the EPA ordered BP to look for less toxic alternatives to Corexit, and later ordered BP to stop spraying dispersants, but BP responded that it thought that Corexit was the best alternative and continued to spray it.”