[Coral-List] Fwd: Gulf Oil Spill, dispersants

[Bill Allison]

A number of list members have suggested that the dispersants could be
problematic and should be investigated. It is ironic and alarming that oil
dispersants inimical to life are being used in unprecedented quantities to
make the problem “go away”, that is, to make it invisible &
coincidentally(?), to make the largely unknown causal chain of environmental
harm much harder to trace. We now have visible oil + invisible oil +
~2,000,000 liters of toxic dispersants in the Gulf, and the meter is still
running - apparently an order of magnitude faster than announced some days
ago.

Although the formula of Corexit, the main dispersant being used is
proprietary, an online search identified some important ingredients as:

- 2-butoxyethanol: organic solvent, toxic, said to kill most arthropods,
biodegradable*.

- sulfonic acid esters: common in many household products such as detergents
& in sulfa drugs (anti-biologics) - toxic (add detergent to an aquarium &
watch).

- propylene glycol: an alcohol used in many household products, readily
biodegradable*.

*BIODEGRADABLE - sounds good BUT: it means that microrganisms break it down,
consuming oxygen in the process. Propylene glycol which I suppose is the
carrier and main component, is said to have a very high BOD. Add to this the
BOD created by the decomposition of creatures large & small killed by oil &
dispersants, and that of microbes feeding on the oil itself. There is
speculation about whether the resultant emulsion will sink or float and an
expectation that the whole mess will disperse and be diluted, so becoming
even more invisible. Recall that many species of marine larvae travel in the
near-surface few millimeters of the sea. Depending on the timing of spawning
events and dispersal, might this have a negative impact on larval
recruitment across a spectrum of marine life?

On the positive side (I’m kidding), Corexit is made in USA, the stock of the
producer has appreciated, & the costs the whole clean-up bundle will be
added to GNP (I’m not kidding). Is that an insane system or what?





-- 
________________________________
Say what some poets will, Nature is not so much her own ever-sweet
interpreter as the mere supplier of that cunning alphabet, whereby selecting
and combining as he pleases, each man reads his own peculiar lesson
according to his own peculiar mind and mood. (Herman Melville, 1852)