I am aware of the EPA tables of tests on mysid shrimp and silverside fish, which do nothing to address my concerns. EPA has conducted no tests.

Alabaster Corporation, manufacturer of Sea Brat 4, (preferred by EPA to Corexit 9500), is quite clear in their statement that "Although Sea Brat is not a bioremediation product Sea Brat is 'Extremely Effective' if used with any microbial or bioremediation products for emergency response or ocean, water environmental pollution."

The blurb refers to the EPA NCP Product Schedule- "This listing does NOT mean that EPA approves, recommends, licenses, certifies, or authorizes the use of SEA-BRAT #4 on an oil discharge. This listing means only that data have been submitted to EPA as required by subpart J of the National Contingency Plan, Sec. 300.915."

Testing seems to have been done only by the manufacturing company. The EPA or other government labs seem not to have done any detailed tests.

Further, "for a heavy crude oil spill use a approximate 5 to 1 ratio. 1 part Sea-Brat concentrate with 4 parts water." This is a large amount, considering how much would be required at the BP spill.

With regard to Corexit 9500A, a 96 hour test by BP on marine life showed that it was twice as toxic as the crude oil gushing into the Gulf.
In a letter, Rep. Markey warned the "release of thousands of gallons of chemicals into the Gulf of Mexico could be an unprecedented, large and agressive experiment on our oceans, and requires careful oversight by the Environmental Protection Agency and other appropriate federal agencies."

(A director of Nalco, manufacturer of Corexit, formerly was an executive of BP.
The product, or at least some numbered Corexit dispersants, have been banned in the UK.