Though predominantly a tropical water problem of the Pacific and Caribbean, ciguatoxin has been found in farm-raised salmon.

There is also some evidence that it can be sexually transmitted.  So never have sex after eating fish--LOL

Always feed your annoying neighbor's cat the fish you plan to eat first.---not really--just kidding--I actually love cats.

It looks like nothing is safe to eat anymore, unless you raise it yourself, or at least no how it has been raised.

Mary

As deep water drilling for oil in the Gulf of Mexico increases, residual toxicity in the fish population will increase, due to several cancer causing solvents used in the drilling, pumping, recovery, derrick maintenance, and tanker shipment operations ALWAYS being spilled. 

But don't ask the OIL companies, with the largest windfall profits in the entire history of capitalism, to fix this, because they 'wink-wink' are not required to, because of their own K Street lobbyists 'bribe-bribe', on both sides of the isles, in the House and Senate, of the US Congress, protection.