"Now the problem with dispersant is this; When you think of 'dispersants', you think it just breaks it apart, and sort of 'dissolves' the oil, and it merely washes away, but not in an oil form. But that is not the case. The dispersant that has been used, that is most effective, also breaks it down, but hugely into a gaseous material, which of course, goes into the atmosphere, and is HIGHLY toxic. Coupled with the other gasses coming up from the well, this is not able to be done safely. It's not just the sludge, that washes up on the beaches, with the dispersant in it that is toxic, which has been reported...though that PART, is also accurate"

My understanding is the purpose of all dispersants is to break oil down into tiny droplets....(and each one has its best conditions for use). This dillutes the oil, takes the oil from the sea surface (sinks it down), and enables bacteria to act on it better (increases the surface area that bacterial can act on).

Most compounds are toxic to a different degree to different forms and stages of sea life at high concentrations. This is also the case for oil and all dispersants. However, my understanding is the scientific assessment (of the any scientists involved) is that the use of dispersants on this oil spill(considering the amounts and the potential impacts on surfaces sepecies and coastal areas)... is a better option than just leaving the oil reach the surface untreated, where it would stay there or move onshore in big amounts.But, didpersing oil is definately not 100 percent effective, especially in these conditions. So, some oil reaches the surface, and the shorelines...but not at the levels that would occur if not used...(and if not used at source).

Oil at the surface gives off considerable toxic fumes....especially at these levels (and, I understand this oil is lighter, which could give off more toxic compouunds to the air) Oil that is dispersed deeper into the vast ocean, would gives off much less toxic fumes into the atmosphere...and would provide a safer working environment at the sea surface site.

While dispersed oil (aka, a plume) can be detected by scientific instruments, I doubt that well-dispersed oil would look much different than regular seawater to the naked eye.