As one expert told ABC7, the best comparison to the dispersants would be paint thinner. They are alcohol-based but organic in nature, and while toxic, they have been approved for use by the EPA. But oil companies have never used the dispersants in these quantities, causing the critics to come out in force.
A gusher at the bottom of the Gulf, a trickle of legal documents from a fax machine, and the spray of a dispersant called corexit from planes above the oil spill were all related Wednesday.
"We're left with few options ranging from bad to worse, and maybe even worse than that," Andrea Treece said.
Treece is a lawyer for the Center for Biological Diversity, which has filed a 60-day notice of intent to sue the United States Coast Guard and the EPA if they do not investigate the impacts of dispersants on threatened and endangered species.
"They have never been used in these volumes," Treece said. "BP had dumped nearly a million gallons in dispersants into the Gulf. They have never been used in deep water like this before, so we really don't know the full extent of this from the bottom of the food chain up."
From the outset of this crisis, BP has used corexit, despite critics who say it is more toxic than other products which remain on shore.
According to experts, all dispersants are toxic and have many of the same ingredients, but others say it is not that simple.
"It is a giant science experiment in some ways," Thomas Azwell said.
Azwell used to work on oil rig in the Gulf. Now, he is finishing his Ph.D. in environmental science at UC Berkeley.
"The real question is how long do these chemicals persist in the environment," he said.
Or are they necessary at all? Some critics argue that, if left alone, the oil could disperse naturally. The Center for Biological Diversity, among others, questions if their use has more to do with saving BP's public image.
"There is an element, here, of BP trying to bury the body by keeping the oil beneath the surface, keeping it from shore, making it a lot harder to track," Treece said.
Wednesday afternoon, samples of water from the Gulf arrived at the Lawrence Berkeley National Laboratory. They come from within the oil plume and also from along the edge of the sheen. Terry Hazen, who has expressed concern about the use of dispersants, will conduct tests on those samples to see if the oil is breaking up. He also wants to know how clean or toxic the water may be.