Courtesy uscgd8 Chemicals known as dispersants are now being used against the ever increasing amount of oil leaking out of a deep water well head. Dispersants help break the larger masses of oil into smaller droplets which will mix into the water. These dispersants are being sprayed onto the surface slicks and are also being injected directly into the oil flowing out almost a mile under the surface.
Officials said that in two tests, that method appeared to be keeping crude oil from rising to the surface. They said that the procedure could be used more frequently once evaluations of its impact on the deepwater ecology were completed. New York Times
Dispersant chemicals contain solvents to assist it in dissolving into and throughout the oil mass and a surfactant which acts like soap. Surfactant molecules have one end that sticks to water and one end that sticks to oil. This, along with wave action, breaks masses of oil into droplets small enough that they stay suspended under water, rather than floating back to the surface.
Such cleanup products can only be used by public authorities responding to an emergency if they are individually listed on the National Contingency Plan Product Schedule.
Many of the first dispersants used in the 70s and 80s did show high toxicity to marine organisms. However, today there is a wealth of laboratory data indicating that modern dispersants and oil/dispersant mixtures exhibit relatively low toxicity to marine organisms.
On occasions the benefit gained by using dispersants to protect coastal amenities, sea birds and intertidal marine life may far outweigh disadvantages such as the potential for temporary tainting of fish stocks. ITOPF
Here is a link to one product on their list (Oil Gone Easy Marine S200
According to National Geographic News, "Dispersants only alter the destination of the toxic compounds in the oil." Moving the oil off the surface protects the birds and animals along the shoreline but will increase the oil exposure for fish, shrimp, corals, and oysters. I hate to mention what hurricanes will do to this situation.