[TheMentat]

I think there are plenty of absorbent materials that can be used, some of which are already being used.

Just to play devil's advocate with this particular product... dumping thousands of tons of fertilizer into the gulf of mexico would wreak havoc of the environment. The resulting algae blooms would choke out a huge amount of the marine life. While it would probably still be an improvement over the current situation, there's likely a better alternative.