You would have to eat around 25 tins (at 95g or 3.3 ounces a tin) of it a week before you hit the maximum tolerable intake of mercury. For pregnant people (or people trying to get pregnant), the limit would be around 12 tins (at 95g a tin) a week. It is unlikely many consumers will reach these limits.
Poisoning from methylmercury can take weeks or months to appear. A chemical spill with elemental mercury or inorganic mercury might give you symptoms more rapidly. Mercury poisoning is diagnosed by testing your blood and urine for mercury levels.
Can you get mercury poisoning from fish? Yes, certain types of fish contain methylmercury, which is present in the water where fish live. Methylmercury is a type of organic mercury that is dangerous to the human body if you consume large amounts of it.
The Dietary Guidelines for Americans recommends at least 8 ounces of fish per week (based on a 2,000 calorie diet) and less for children. Those who might become or are pregnant or breastfeeding should eat between 8 and 12 ounces of a variety of fish per week, from choices that are lower in mercury.
Blood mercury levels above 100 ng/mL have been reported to be associated with clear signs of mercury poisoning in some individuals (e.g., poor muscle coordination, tingling and numbness in fingers and toes).
Exposure to mercury – even small amounts – may cause serious health problems, and is a threat to the development of the child in utero and early in life. Mercury may have toxic effects on the nervous, digestive and immune systems, and on lungs, kidneys, skin and eyes.
Government dietary guidelines recommend that people eat fish twice a week. And we know that fish are full of omega-3 fatty acids—which can benefit both heart and brain.
Commercially sold fish that may contain high levels of mercury include shark (flake), ray, swordfish, barramundi, gemfish, orange roughy, ling and southern bluefin tuna. In freshwater environments containing mercury, some species of fish may contain high levels of mercury.
For most people, the risk from mercury by eating fish and shellfish is not a health concern. Yet some fish and shellfish contain higher levels of mercury that may harm an unborn baby or young child's developing nervous system.
Foods with sulfur: Foods rich in sulfur, like garlic and broccoli, may help with removing toxic metals. Supplements like selenium, alphalipoic acid and glutathione may also help with mercury toxicity.
Choose fish and shellfish that are lower in mercury such as salmon, trout, tilapia, cod, sole, sardines, shrimp, oysters, and other shellfish. For the most health benefits, choose fatty fish such as salmon, trout, herring, chub mackerel, and sardines. o These fish have healthy omega-3 fatty acids.
Elemental (Metallic) Mercury
Metallic mercury mainly causes health effects when inhaled as a vapor where it can be absorbed through the lungs. Symptoms of prolonged and/or acute exposures include: Tremors; Emotional changes (such as mood swings, irritability, nervousness, excessive shyness);
The traditional treatment for mercury poisoning is to stop all exposures. In many cases, chelation therapy is also used. This involves giving a medication (the chelator) which goes into the body and grabs the metal (chelos is the Greek word for claw) then carries the metal out of the body, usually into the urine.
Children under six can eat up to three 3-ounce portions per month. Older children and adults can safely eat it once a week. But look out for "gourmet" or "tonno" labels. They are made with bigger yellowfin tuna and can contain mercury levels comparable to canned white.
Salmon is low in mercury.
Farmed salmon has on average, 0.05 micrograms of mercury per gram. This is well below the levels deemed safe for women and children by the FDA and EPA, which inform the United States Dietary Guidelines for Americans (DGA).
The United States Food and Drug Administration recommends keeping the consumption of albacore (white) tuna to under 4 ounces per week and skipjack (light) tuna to under 12 ounces per week. These amounts should be lower for children and women who are or may become pregnant.
Packed with nutrients for a healthier you
With half the calories of salmon, Barramundi is still packed with Omega-3 fatty acids (known to promote both brain and cardiovascular health) and boasts 21 grams of lean protein in a four-ounce serving.
The biological half-life of mercury is estimated to be approximately 30 to 60 days in the body [4]. The half-life of mercury in the brain is not entirely clear, but is estimated to be as long as approximately 20 years.
Once in your body, metallic mercury can stay for weeks or months. When metallic mercury enters the brain, it is readily converted to an inorganic form and is “trapped” in the brain for a long time. Metallic mercury in the blood of a pregnant woman can enter her developing child.
Certain nutrients such as Selenium, Vitamin C and E, and Glutathione help with mercury removal. Adding these nutrients in your diet can go a long way in preventing mercury toxicity. Besides, high doses of chlorella, a green algae, has also been proven helpful in reducing body mercury levels.