Mercury is known to bioaccumulate in humans, so bioaccumulation in seafood carries over into human populations, where it can result in mercury poisoning. Mercury is dangerous to both natural ecosystems and humans because it is a metal known to be highly toxic, especially due to its ability to damage the central nervous system.
Fish and shellfish concentrate mercury in their bodies, often in the form of methylmercury, a highly toxic organic compound of mercury.
Species of fish that are long-lived and high on the food chain, such as marlin, tuna, shark, swordfish, king mackerel, tilefish (Gulf of Mexico), and northern pike, contain higher concentrations of mercury than others.
The last researches showed that 100 gr of this canned fish contains for 15 to 40 ml mercury.
Tuna is a rich and very useful ingredient which can also be used like addition in salads.
But, the American nutritionists, with researchers, have shown how often is normal to have a tuna meal.
They also approved the presence of mercury and some other heavy metals. This is because the tuna is migrating fish. On this way may appropriate a lot of heavy metals and harmful materials that cause pollution of the sea. The mercury can`t disappear when the tune is canned.
Canned tuna contains 15-40 ml mercury, but fresh tuna contains 2 times more!
So, the canned tuna reduces the harmful materials. To avoid complications in the digestion, loss of memory, the nutritionists advise eating tuna moderately!
This information is not news! The panic about poisoning with mercury tuna began in 2004 by the Food and Drug Administration for pregnant women.