"High Mercury Levels Are Found in Tuna Sushi"

Recent laboratory tests 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.

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. The sushi was bought by The New York Times in October.

“No one should eat a meal of tuna with mercury levels like those found in the restaurant samples more than about once every three weeks," said Dr. Michael Gochfeld, professor of environmental and occupational medicine at the Robert Wood Johnson Medical School in Piscataway, N.J.

Dr. Gochfeld analyzed the sushi for The Times with Dr. Joanna Burger, professor of life sciences at Rutgers University. He is a former chairman of the New Jersey Mercury Task Force and also treats patients with mercury poisoning.

The owner of a restaurant whose tuna sushi had particularly high mercury concentrations said he was shocked by the findings. “I’m startled by this,” said the owner, Drew Nieporent, a managing partner of Nobu Next Door. “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.”

Although the samples were gathered in New York City, experts believe similar results would be observed elsewhere...

No government agency regularly tests seafood for mercury.

Tuna samples from the Manhattan restaurants Nobu Next Door, Sushi Seki, Sushi of Gari and Blue Ribbon Sushi and the food store Gourmet Garage all had mercury above one part per million, the “action level” at which the F.D.A. can take food off the market. (The F.D.A. has rarely, if ever, taken any tuna off the market.) The highest mercury concentration, 1.4 parts per million, was found in tuna from Blue Ribbon Sushi. The lowest, 0.10, was bought at Fairway....

In general, tuna sushi from food stores was much lower in mercury. These 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. Mercury enters the environment as an industrial pollutant...

Some environmental groups have sounded the alarm. Environmental Defense, the advocacy group, says no one, no matter his or her age, should eat bluefin tuna...