Fair point, it's somewhat hyperbolic phrasing. A perhaps somewhat retroactive defence: Surface contamination is deadly, particularly to bird/shore life, but d

Fair point, it's somewhat hyperbolic phrasing. A perhaps somewhat retroactive defence: Surface contamination is deadly, particularly to bird/shore life, but dispersed oil is deadly throughout the water column (until it resurfaces, at which point it becomes deadly to birds again). There's relatively little life at the surface compared to the pelagic zone, so the impact of dispersants doesn't merely multiply the effect of the oil by the depth of the water, but actually moves that oil into the regions where life is densest.