Thomas Bridgeland wrote:

> There was a serious mass poisoning in the 50s here in Japan. Mercury
> from a factory contaminated the Minamata bay and many who ate the fish
> over time developed severe symptoms and died. Just a year or so ago
> some fish from that bay are now being allowed to be eaten.
>
> But it is hard to go from such an acute case to the far lower levels of
> mercury in deep sea fish like tuna or salmon. Not really comparable.
>
The article I cited talked about this incident. Here it is again:
http://www.pubmedcentral.gov/articlerender.fcgi?tool=pubmed&pubmedid=12844364
this is the full article, free (as in beer).