[Vince Ferrer]

What about ridding the oceans of mercury so we can all eat more fish without getting sick?

That's probably a yes/no answer. We probably can devise a way to extract mercury. However, there is so much mercury in the ocean, on the sea floor, and coming in from rivers that any attempt probably wouldn't make a difference. It is an environmentalist scare that mercury comes from coal plants, which it does. However, it also is contained in the rocks and soil, and leaches out into water and is carried by rivers into the ocean. So mercury is added to the ocean whether or not we burn coal. Better pollution controls on power plants may help some, but I think it is just there naturally as well, and the effort to get rid of it is not economical.

[who_would_fardels_bear]

Then we need to stop the rivers from flowing into the oceans.

That will also help to keep the seas from rising and inundating the world's coastal regions due to Global Warming.

/sarc

[Does so]

Mercury is also used to capture gold from riverbeds.