State officials say new test results on mercury levels in blue marlin jerky, a popular snack in Hawaii, show the product is safe to eat.

But not everyone is convinced. Researchers and public health advocates say new information about the danger of mercury needs to be considered.

Hawaii Health Department officials sent samples of the jerky to labs run by the U.S. Food and Drug Administration last year after a study by a California physician found alarming levels of mercury in the dried fish that is sold throughout stores in Hawaii. The researcher, Jane Hightower, found that mercury levels in marlin jerky were five to 28 times federal safety limits.

But the FDA results don’t corroborate Hightower’s findings. They show that mercury levels in marlin are below the federal safety limits, which is what state officials previously believed. When Hightower’s study was released, the state health department said she overestimated the health risk.

The average mercury content in the new samples were slightly above the safety limit of the FDA. However, the methylmercury content — which health officials say is the type of mercury that people need to be concerned about — was found to be much lower, about one-third of the FDA limit and slightly below the limit set by the Environmental Protection Agency, which has a stricter standard.

Physicians and scientists have tied high levels of mercury to neurological defects in fetuses. Pregnant and breast-feeding women, as well as infants, are advised to strictly limit their intake of fish. There are no federal laws or regulations governing mercury consumption in adults, but very high levels can lead to mercury poisoning.

Hightower, who said she sent her samples to four different labs to make sure the results were accurate, was skeptical of the FDA’s findings.

She said that the fishing industry had argued without evidence in a 1970s FDA court case setting the limits of mercury that it was only methylmercury that was dangerous.

“No one ever proved the other mercury compounds in fish are safe then, nor now,” she said by email. “In fact, I suggest the FDA do more testing to tell us just what mercury compounds are there, instead of being dismissive. This is a very unusual test result. Most fish have 90-95% of their mercury as methylmercury.”

Hawaii’s health department has long maintained that blue marlin is different from other types of fish in that most of the mercury that’s found in the marlin is not methylmercury, as its new tests confirm. Tests conducted a decade ago by the department found that while all other species of fish had almost 100 percent methylmercury, methylmercury only made up one-fourth of the mercury found in blue marlin.

There is general consensus in the scientific community that methylmercury is more toxic because it is more readily absorbed in the body, according to Renee Sharp, a senior scientist at the Environmental Working Group, a nonprofit focused on public health and the environment.

But the safety of regular mercury is less clear.

“It’s not really a blessing to say that most is mercury,” said Ned Groth, a physician who has done extensive research on mercury.

He also said that the FDA’s current limit for mercury content in fish couldn’t be defended any more given new knowledge of its risks — he said it should be much lower.

“It’s at least three or four times higher than it should be,” he said.

But the FDA, which was sued last month by environmental and consumer protection groups for not creating stricter standards and policies to protect the public from the potential dangers of mercury, doesn’t agree.

“There has never been a documented case of adverse effects (i.e. deficits in health and mental faculties) in an individual in the U.S., resulting from eating commercially bought seafood,” Curtis Allen, an FDA spokesperson, said via email. 

As to marlin jerky specifically, he said the public didn’t need to worry.

“The levels of methylmercury in marlin jerky are not expected to result in exposures approaching any level of health significance because this type of product is a snack food which is consumed infrequently and in much smaller amounts than the non-jerky fish people eat,” he said.

As to the lawsuit, he said that the FDA couldn’t comment on pending litigation.

While Hightower and state health officials don’t agree on how much mercury blue marlin jerky contains, they agree that pregnant women shouldn’t eat it at all. That goes for shark and swordfish, too. The department’s recommendations for pregnant women can be found here.

To find out if you are consuming mercury levels above the EPA’s limit for pregnant women, check out this easy to use mercury calculator, developed by GotMercury, a project of the Turtle Island Restoration Network.

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