In a perfect world, fish would be a near-perfect food. It's high in protein and full of essential nutrients and healthy fats. Unfortunately, nearly all fish are contaminated with mercury. And, because it's bioaccumulative, mercury is found in higher concentrations of larger, older fish and predatory species like shark, tuna, and swordfish. If you eat fish often, to protect your health, you should know how much mercury you may be ingesting based on your weight.
Now, there's now an easy way to find out. GotMercury?.org has created a online calculator to do just that. Type in your weight, along with the type and amount of fish you eat each week, and its calculator will instantly tell you whether your consumption exceeds the EPA's recommended limit.
For example, the site lists a recent study (by Turtle Island Restoration Project) about the mercury levels in swordfish. Some 68 percent of swordfish samples tested were above the FDA Action Level of 1 ppm mercury and 16 percent were more than 2 ppm, more than twice the FDA's Action Level. The average mercury concentration found: 1.38 ppm, 38 percent higher than the FDA Action Level.
Gotmercury?.org