Superfish
A Warning to Seafood Lovers

Seafood lovers take note: there’s good news and bad news.

First, there’s the bad news for those who enjoy tuna on rye.

High concentrations of mercury, a neurotoxin that can damage developing brains in fetuses, are found in some kinds of popular fish such as albacore tuna. Swordfish and shark, king mackerel, marlin, orange roughy and tilefish also contain dangerous levels of mercury.

Women of reproductive age and young children are advised to avoid these types of fish and limit overall consumption of all fish to no more than 12 ounces per week, according to the Food and Drug Administration, as it takes months for the body to rid itself of mercury.

The danger from mercury is not just to developing brains. There is evidence to suggest an association between mercury exposure and heart disease, making it dangerous for everyone, but especially those who are already at risk.

The American Heart Association, however, recommends eating fatty fish at least twice a week because it is high in omega-3 fatty acids which are believed to help lower rates of heart disease, reduce hypertension, relieve some arthritis symptoms and prevent cancer. Fatty varieties that are low in mercury include herring, sardines, and wild salmon. Some popular fish that are also good choices include sole, tilapia, clams and oysters.

“It all depends on your diet — you can’t eat a lot of big, wild fish,” said Tim Fitzgerald, a marine scientist for Environmental Defense Fund, who provides health consumption information to Monterey Bay Aquarium’s Seafood Watch.

The problem with large, predatory species like marlin and swordfish is that they contain much higher levels of mercury than small fish, such as anchovies and sardines, because of the way mercury moves up the food chain. “Sharks, marlin, polar bears and people at the end of the food chain have the highest concentration of mercury,” Fitzgerald said.

It’s sometimes difficult for consumers to make seafood choices that are good for their health — and the environment. According to Tim Fitzgerald, “Billions of pounds of imported fish come into the United States annually, and less than one percent is tested for environmental toxins by the FDA.” Because marlin is not a popular dining choice in the U.S., many people are not aware of this. And while the FDA is the regulator body that creates consumer advisories about mercury for pregnant women, they actually do very little testing for this neurotoxin.

Another problem with the advisories is that they are not terribly specific and there’s a lot of room for interpretation, according to Fitzgerald. It’s also difficult for consumers to make the best seafood choices because sometimes what’s best for the environment is not always best for their health, and vice versa. For example, blue marlin and striped marlin from Hawaii are fairly resilient to fishing pressure and are listed as “good” alternatives for the environment on Seafood Watch. But, Seafood Watch also lists a health advisory for these fish, due to high levels of mercury. Monterey Bay’s other regional pocket guides provide further guidance for consumers and note that imported blue marlin and striped marlin should be “avoided.”

So, for U.S. consumers, the situation is “buyer beware — eat with caution,” but certainly not to give up on all fish. Consumers may just need some help from Monterey Bay’s Seafood Watch, which maintains a list of “which seafood to buy and why,” including a comprehensive seafood search, regional seafood guides — and printable pocket-sized guides for your wallet.

And, if you are a tech-savvy-seafood-lover, a “fish phone” may be more of what you’re looking for. Environmental Defense Fund’s Seafood Selector to-go allows mobile web users to look up their seafood guide on a blackberry or iPhone and download the information.

Ultimately, it’s ideal to exercise moderation and caution when eating seafood by taking into account both environmental and health concerns. Fortunately you don’t have to wonder whether the seafood menu at your favorite restaurant is environmentally friendly, the answers to your questions may just be a text-message away.

  • leanna

    i waint the one were giraffes give birth
    a wonder of life. yawn…. so were is it
    then!

  • Gianmario

    i live in italy , and here we often go to fishing “big game” and what surprised me is how big and bad billfish can become .. i have an enormous respect for this giant predators

  • Franco

    Mercury is also dangerous to adults not only chindren. It impairs important antioxidant systems and in turn, the brain becomes more susceptible to other environmental toxins, such as pesticides and air pollution, which in these days, we are constantly exposed to. We should let big fish alone and eat only farmed fish. This would be good for environment and for health.

  • semilog

    I didn’t see any good news. Why?

  • Savannah

    Ya where is all the good news I just saw bad news!!!!!!

  • Jason

    That is because there is no good news and it will only get worse.You can thank your fellow human beings for that. Where do you think all the mercury came from?

  • john

    The real problem is the collapsing fish population throughout the world’s oceans. We are way too greedy and efficient at capturing fish and there is little market pressure to be sensible and manage well. We should all stop eating so much fish. I was in a grocery at 8000 ft. in Colorado and they had every variety of ocean fish up there – we cannot sustain this kind of depredation on the oceans much longer. And when something goes extinct, that’s it.Which species will be the keystone that leads to disaster? No one knows. So eat up.

  • dom

    big corps. have been dumping toxins in the ocean since world war 2. if youre foolish enough to eat anything out of the giant waste basket we call the ocean,HAVE AT IT!!

  • Andy Marks

    The good news is overfishing will eliminate poisonous fish permanently! Wah, you don’t like black humor?

  • HT

    Well the big problem with farmed fish lies in what they are fed. Currently any farmed Salmon will NOT have the OMEGA 3 fatty acids which is the main benefit from eating WILD (natural life in the wild) fish such as Salmon.

  • http://midlandseventsphotography.co.uk/links/ Midlands Photographer

    Like your stuff, really enjoying the read.

  • Tony G

    Too bad, this article is not in touch with reality. I could have been truthful and informative. Now these people think they have been a little more educated, crazy stuff! It’s amazing how little people don’t know yet they proclaim to be experts! Hurry, follow them off the cliff!

  • TJFish

    It’s a disservice to the public to keep harping on the “dangerous levels” of mercury in certain species of fish. The advice based on misapplied studies and misunderstood results. Concern for public health and marine fish stocks is good. Basing it on flawed arguments only muddies the picture.

    The exposure limits for mercury set to amounts that are very far below the amounts that produce detectable pahtology. It’s something like 1/1000th of that amount. What’s not reported are the levels of selenium in the fish counter act any potential damage from mercury.

    Nutritional studies show that increasing the intake of selenium reduces the effect of mercury and helps the body eliminate it. The facts run counter to popular “knowledge”. If you’re concerned about mercury intake, eat more tuna, especially Yellowfin tuna.

  • steve

    Tony G is obviously invovled in the fishing industry. Their’s’ a not a problem attitude’. Close minded moron!

  • Frank Rizo

    ^ Totally agree, Steve. As well as TJFish. Not to worry, if we carry on with current practices, and knowing mandkinds’s track record we will, all ocean life is projected to collapse by 2048. And don’t think that only consuming farmed fish will help. Farmed fish are fed fishmeal made from 20-30 million metric tons of wild caught forage fish. Put differently, farmed fish eat about 25% of the global fish catch. Not to mention these farms release huge amounts of pollution and disease into the ocean waters.

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