Although outgoing BP CEO Tony Hayward alleged that the mud BP is using to seal the well in the Gulf is not toxic, a congressional investigation has revealed that the mud is a highly toxic chemical mixture containing ethylene glycol and lye. Rep. Lois Capps (D-CA) asserts, "Time and time again, BP has failed to disclose critical data and information that is essential to our ability to track the long term effects of this spill."