Thanks for the context. Simple is good. :)
And if the only effect that’s being looked at in acute toxicity tests is death, true exposure to an oil spill isn’t a carbon monoxide gas chamber...so there are no long term effects to long term exposure ?
Well, "death" is certainly not the only effect that is looked at in acute toxicity studies. Any symptoms noted before death are certainly noted and recorded. And certainly any high-level exposures to humans will record any and all symptoms that can be measured at the time. The folks that work at chemical plants are our "canaries", as some of them will be exposed, despite the best efforts to prevent such exposure.
But the point that I'm trying to get to is that for there to be "long term effects" there usually has to be "long term exposure" above some threshold value. There are very few chemicals that have sufficiently irreversible effects that a single exposure to other than a very high high level will cause such a problem. In fact, at the moment I can't think of a single chemical that will do so from "chemical effects" alone. The ONE case that occurs to me is exposure to radioactive iodine from a nuclear reactor breach or bomb, and that is because the thyroid is so efficient at grabbing onto iodine and not letting go that the thyroid gets a fatal dose. And all the measurement data that I have seen for pretty much every toxin associated with the spill have been at such low levels that I just don't see how there could be significant problems.