For those of you interested in your food choices, here is an interesting article, The Danger of Not Eating Tuna. I like to mix up canned salmon (or tuna) with relish, spices, and mayo and put it on toast for a tasty and somewhat healthy lunch choice. So, I'm always interested in reading about mercury in fish and/or the benefits of eating fish.
Here are a few excerpts from the article:
Just so we know, which fish are higher and which are lower in mercury?
Shellfish are almost all low in mercury because they don't live very long and they're small: shrimp, lobster, crab, scallops. And shellfish have medium levels of omega-3s, similar to other medium-size fish. Salmon are also good. They're high in omega-3s and low in mercury because they're also short-lived.
Light tuna is low in mercury, compared with white (albacore) or red (bluefin) tuna. On average white tuna has three times the mercury as light tuna. But on average white tuna has three times the omega-3s as light tuna — and all the evidence that we can see suggests that omega-3s have more benefit than mercury has harm.
The bottom line
The bottom line is that there's inconclusive evidence that mercury has any long-term effects in adults at the levels that are commonly consumed, and that even if there are effects, studies suggest that they are only to lessen the benefit of the fish. That's important from a public health perspective — we might be getting even more benefit from fish on a population level if we took the mercury out, and that's a very important question that should be answered. But that doesn't mean that the individual person trying to decide on a fish meal should worry about mercury.
I know I sound like I'm trying to downplay the risk but I really think we are experimenting with people's lives when we give recommendations or write stories or reports that make people eat less fish. We know from very good human studies that fish intake reduces the risk of dying from a heart attack by about a third. And heart attack is the number-one cause of death in the U.S. among both women and men. It's the number-one cause of death in almost every country in the world. And eating fish once or twice a week reduces that risk by a third. So if we're causing people not to eat fish or to choose to eat something other than fish because they're worried that the fish has some mercury in it, they're increasing their risk of dying from a heart attack for a concern that has not been established.