Recent lab tests, the New York Times reports, have found so much mercury in bluefin tuna--a popular item in sushi restaurants from coast to coast--that a diet of six pieces a week would exceed the maximum levels recommended by the US Environmental Protection Agency (EPA).
Owners of sushi restarants implicated in the study expressed astonishment at the findings, which also concluded that sushi from five of the 20 establisments tested could be shut down for exceeding acceptable mercury levels. Mercury levels included in the study were far greater than those found in canned tuna, which itself was the subject of a warning from the EPA and the federal Food and Drug Administration, who issued a statement in 2004 that children, pregnant women, and women who might become pregnant should avoid eating certain kinds of canned tuna. More recent studies have indicated that mercury may also cause health problems in adults, including neurological symptoms and cardiovascular disease.
Meanwhile, there are other (environmental) reasons to avoid bluefin tuna. As of last year (and for the next four years), Japan's annual quota for southern bluefin tuna has been cut in half, making it severely overfished, and its allotment of Atlantic bluefin has been reduced by almost 25 percent, because of shortages. The Washington Post reports that sushi restaurant proprietors are selling the fish at a substantial loss, and imports of tuna into the United States have dropped 24 percent, and last year, the US actually implored other nations to completely ban bluefin tuna fishing for three to five years until stocks can be replenished. Now the bluefin tuna population is threatened with extinction.
OK, that's the bad news. The good news is, there are alternatives! Several tuna purveyors deal in low-mercury, "safer" alternatives--chief among them Kona Kampachi tuna, AKA Kona Blue, a sustainably farmed fish which has, since at least last year, been catching the attention of sushi and other high-end chefs looking for sustainable alternatives to conventional farmed fish around the country. The fish receive no antibiotics or medications, and their food comes from sustainable wild fisheries and organic sources. Another alternative comes from Wild Planet, a sustainable seafood enterprise that produces "minimal" and "low" mercury tuna--meaning fish that average less than 0.15 parts per million of mercury, thanks in part to their small size when caught--between nine and 25 pounds, compared to the 70-plus-pound fish that are caught in traditional line fishing.
Much, much more information (and many more resources for those seeking non-mercury-contaminated alternatives to conventional bluefin tuna) can be found at the International Commission for the Conservation of Atlantic Tunas, which works to conserve tunas "and tuna-like species" in the Atlantic Ocean.
Thanks for this important post and for letting people know that overfishing is an issue too. I just wanted to add that Environmental Defense has a seafood selector that considers fishing/farming practices as well as mercury and PCB contamination to rate popular seafood as Eco-Best, Eco-Ok, or Eco-Worst. You can also find alternatives to your favorites if they are on the Eco-Worst list. You can find it at www.EnvironmentalDefense.org/Seafood.
Keep up the great work!
Substantial bodies of research in cultures which consume vastly more fish than our own do not indicate any added risk from eating tuna or other high mercury fish. However, the potential to wipe out the wild stocks of bluefin tuna are quite real and present dangers. More substantial international compacts must be completed with enforceable restrictions on bluefin catch, especially by the Japanese. In lieu of this, the red herring scare tactic of "eat tuna and die" will suffice to limit demand, and offer an acceptable "we don't serve" excuse to restaurants which try to make a difference by not serving bluefin.
I think one of your links is broken (Wild Planet drops you on a job posting) but thanks for the heads up on Kona Kampachi. I just wrote about it and the Mercury News.
You guys are usually so right on with your sourcing that I was a little surprised by the misstatements in this piece. Kampachi (aka kanpachi) is not a tuna, it's a jack in the Carangidae family. There's enough trouble with mislabeling fish that we shouldn't be lumping non- tunas with tunas, especially when they have such different life histories.
I don't know if you have some direct experience with the companies you site but otherwise you might as well give a laundry list of testing businesses and programs, including CleanFish, SafeHarbor, and Ecofish. The general rule for getting less mercury is choosing younger fish, which have eaten less mercury-laden prey, or to avoid top predators like tunas and swordfish. Since Hg is taken up by bacteria and phytoplankton, you can't completely avoid it in the sea.
Finally, citing ICCAT as the place to go for information about tuna is like sending folks to the fox to learn about chicken. ICCAT's errant quotas and lack of enforcement by member countries are directly responsible for the declines of Atlantic tuna. Even the Bush Administration has said ICCAT is too lenient. Glad to hear you like their mission statement, though.
Most of our family tuna consumption comes from our local sushi restaurant, which provides NO information about origins... I hope this post inspires many to ask questions so restaurant keepers feel an obligation to source responsibly and inform their customers.
For those interested in sustainable fisheries, here's another interesting discussion with Tech Awards winner Rodrigo Pizzaro about solutions for sustainable salmon farming: http://sic.conversationsnetwork.org/shows/detail3475.html