Dispersants are the hot topic about the gulf spill this week, and we are getting alot of questions from reporters about which dispersant is most toxic and whether BP has made the right selection. But the truth is that the toxicity of the dispersant per se is probably the least of our problems: the crude oil spewing out of the bottom of the ocean is 10-100 times more toxic than the dispersant, and there is at least ten times more oil in the sea at this point than dispersant chemical.
We've put together a video below to start to answer some of these questions.
The most important questions people should be asking about the dispersants are NOT which one is least toxic while sitting on the shelf (except with regard for worker protection, which merits great attention). The important questions concern:
- Will any of these dispersants actually be effective? Will they abate a great percentage of the smothering oil plume from reaching the shoreline or will they have only a trivial effect? We are flying blind on this one because we have no experience with applying dispersants at depth.
- What is the toxicity of a chemically dispersed plume? When the dispersant mixes into the crude oil, it creates a mixture that chemically and physically is neither oil nor dispersant -- it is a new "formulation" of mixed compounds. Is this mixture more or less toxic than what we started with? And is a Corexit dispersed plume chemically distinct from a Dispersit dispersed plume? We are flying blind on this one because we have not required toxicity testing data on dispersed plumes.
- Will chemical dispersants keep the oil plume from naturally degrading over time? Will these chemicals slow down or accelerate the process of biodegradation? Again we are flying blind on this one because we have not adequately studied the biodegradation of any chemically dispersed plumes.
Last question: Why are we flying blind on all these important questions?