Press Release

U.S. Geological Survey Mercury Study Misleads Americans About Seafood and Health

Washington — A new study about mercury in the Pacific Ocean is completely irrelevant to consumers who eat tuna and other marine fish, the nonprofit Center for Consumer Freedom (CCF) said today. U.S. Geological Survey (USGS) scientists, whose work was published today in the journal Global Biogeochemical Cycles, tested only ocean water, not fish. Despite the lack of any new data on mercury levels in actual seafood, a USGS press release claimed that “increased mercury emissions from human sources … contaminate tuna and other seafood.”

In a recently concluded legal case which struck down a demand for warning labels on tuna cans, two different California courts found that virtually all the mercury traces in tuna and other ocean fish are “naturally occurring.”

And today’s USGS study can’t dispute the December 2003 findings of Francois Morel, the noted Princeton University geochemist. Morel’s research found that mercury levels in Pacific Ocean tuna did not increase at all during a 27-year period, despite a significant increase in human-generated atmospheric mercury.

“No matter how much mercury is in ocean water, the levels in actual fish aren’t increasing,” said CCF Director of Research David Martosko. “And the entire medical literature still contains zero U.S. mercury-poisoning cases related to eating commercial fish. Even Jeremy Piven is eating tuna tartare again.”

CCF also took issue with the USGS scientists’ failure to test any seafood. “It’s the Food and Drug Administration’s job to tell us what’s safe to eat,” Martosko said. “And the latest FDA report says we should be looking at all the health benefits of eating fish. Hand-wringing about mercury in ocean water isn’t terribly useful.”

The USGS study ignored evidence that most mercury in the oceans originates from undersea volcanic activity, and from geothermal vents in the ocean floor. And it paid no notice to emerging science indicating that plentiful selenium in marine environments may be minimizing the absorption of mercury by ocean fish such as tuna.

“Saying that human activity is putting any mercury into ocean fish is a wild guess,” Martosko added. “And it’s reckless to suggest that tuna and other marine fish are somehow unsafe to eat.”

A Center for Consumer Freedom report, Tuna Meltdown, found that more than 250,000 children in low-income households were born at risk of IQ deficits because their mothers were needlessly scared to eat tuna while they were pregnant. To read this devastating study, visit

Founded in 1996, the Center for Consumer Freedom is a nonprofit 501(c)(3) organization devoted to promoting personal responsibility and protecting consumer choices. For more information, visit


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