Mircrobial Ecologist Terry Hazen, who claims microbes have eaten away BP's undersea plumes of hydrocarbons, had some interesting things to say about dispersants used in previous oil disasters. See end of article for more information on Hazen's recent plume 'research'.
Bioremediation: The Hope and the Hype for Environmental Cleanup, Univ. of California Television, October 8, 2007:
Terry Hazen discusses when it's best to resort to engineered bioremediation of contaminated sites, and when it's best to rely on natural attenuation. Recent advances have greatly broadened the potential applications for bioremediation. At the same time, scientists' knowledge of biogeochemical processes has advanced and they can better gauge how quickly and completely contaminants can be degraded without human intervention.
Dispersant discussion at 3:00 minutes in:
h/t RP Siegel of TriplePundit
Deep-Sea Oil Plume Goes Missing, ScienceNews, August 25, 2010:
Hazen says, those bugs have been so voracious that for one plume of oil his team had been following, “within the last three weeks we no longer detect a deep plume. At all.” ...
Hazen’s interpretation has its skeptics. “Most of the science associated with this spill has been oversimplified,” says John Kessler, a chemical oceanographer at Texas A&M University in College Station. ...
Although the few molecules described in the new paper in Science may well have degraded within weeks, Kessler says, “there are others that have much longer half-lives—on the order of years, sometimes even decades.”
Moreover, he points out, many of the tools traditionally used to gauge biodegradation don’t work well in the field. A few teams have lately begun transitioning to use of more sensitive probes, he says.
And data from those more sensitive tools are fueling his skepticism of Hazen’s report that microbes have been erasing deep-sea plumes. As recently as August 22, Kessler says, “I spoke to some of those researchers out there [in the Gulf], and they told me they were still seeing plumes.”