In case you needed another reason not to consume the dangerously overfished bluefin tuna: This week, The New York Times had a story about a study of mercury contamination, conducted by the newspaper, of leading sushi restaurants in New York. Guess which species showed the highest level of mercury? In the study, the Times collected samples of tuna sushi from leading restaurants like Blue Ribbon Sushi and Nobu Next Door. The results “found so much mercury in tuna sushi from 20 Manhattan stores and restaurants that at most of them, a regular diet of six pieces a week would exceed the levels considered acceptable by the Environmental Protection Agency.”

In addition, the Times noted that “sushi from 5 of the 20 places had mercury levels so high that the Food and Drug Administration could take legal action to remove the fish from the market.” In a sidebar about the health risks related to mercury, the Times noted that “several studies have concluded that elevated mercury levels may be associated not only with neurological problems but with cardiovascular disease among adults as well.”

Sushi made from bluefin showed the highest level of mercury. As the Times report noted, their findings “reinforce results in other studies showing that more expensive tuna usually contains more mercury because it is more likely to come from a larger species, which accumulates mercury from the fish it eats.” In addition to the high levels of mercury found in bluefin tuna, there is also the consideration that the population of the mighty fish is under such pressure that many are calling for an Atlantic-wide moratorium on catching bluefin.

The findings prompted famed restaurateur Drew Nieporent (owner of Nobu, Nobu Next Door, and Tribeca Grill) to comment: “I’m startled by this. Anything that might endanger any customer of ours, we’d be inclined to take off the menu immediately and get to the bottom of it.”

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This is not just a problem in New York’s sushi bars. Today, in a bit of serendipity, Oceana released a study showing high mercury levels in fresh tuna, other sushi, and swordfish from sushi bars and grocery stores from cities across the country. I hope that others who sell sushi and other fish also take the FDA warnings on mercury and seafood to heart, and also get on board and support efforts to reduce the amount of mercury that finds its way into our oceans (and ultimately our diets).