I was interested in Aajonus' theory that we do not absorb the mercury from raw fish, but do with cooked fish. Why do fish which have eaten fish (raw) test high for mercury? Also, I have read stories of big sushi eaters complaining of mercury issues.
As I mentioned in my Spring 2007 newsletter, there could be several reasons that mercury is not absorbed when we eat it raw. Usually, I do not like to theorize on reality because my theory could be wrong. Many people think because a theory is wrong, reality is also. Because the "roosters'-crowing-caused-sunrise" theory was wrong, the sun did not stop rising. With that said, here is my theory:
Little fish eat substances containing mercury. The bodies of those fish try their best to prevent damage from that mercury by depositing it in fat. Each fish that eats those fish further isolates and controls contamination and injury by producing more complex fats. By the time it gets to our plate, it is so contained in that fat that our bodies either cannot digest it or our bodies are able to identify the mass and choose not to digest it. Either way, we do not absorb very much, if any, of the mercury.
When laboratories test anything, first they use solvents to dissolve the substance tested. When fish have been dissolved and tested, tests reveal the amount of mercury contained in that fish, but it does not evaluate how much damage the mercury may have done to the fish prior to fat-isolation.
As I said in my Spring 2007 issue, cooking completely fractionates those fat molecules and releases the mercury. Our bodies absorb the mercury. Therefore, eating cooked fish that is high in mercury contaminates us with mercury.
Your final statement that seems to give foundation to the probability that sushi eaters absorb mercury may not be such evidence. Consider that most human mercury-poisoning in our modern advanced society originates from vaccines, other injections and applying Mercurochrome and Merthiolate (liquid mercury used as "medicinal" antiseptics). Until recently, the mercury from one injection equates to the mercury found in about 4,000 pounds of cooked swordfish. Most vaccines and other injections have the equivalent of the mercury found in 3,300 pounds of fish. I believe that our government blames fish-eating for most mercury-poisoning because they are trying to distract us from the real cause: medication. The government is protecting the pharmaceutical and medical industries, not us. Is it intentional harm for profit and to maintain the status quo or is there a reason more sinister? That is for everyone concerned to investigate.