31 October 2011 – Concentrations of mercury have been discovered in some fish jerky that averaged five times the U.S. government action levels, according to research at California State University, Chico.
The mercury research was conducted by physician Jane Hightower of San Francisco, author of the book, “Diagnosis Mercury: Money, Politics and Poison,” and geoscientist David Brown, chairman of the Department of Geological and Environmental Sciences at Chico. Ms. Hightower is an alum of CSU, Chico.
Ms. Hightower has been investigating mercury in fish for years and was the first in the medical community to raise the red flag about what how pervasive mercury is in top predator ocean fish such as tuna.
She and Mr. Brown extended the study to fish jerky, and the results have been published in “Environmental Health,” a peer-reviewed scientific journal.
Mr. Brown, whose expertise is in environmental monitoring, was responsible for identifying and acquiring samples of the fish jerky products. He also verified that the fish species investigated (marlin and Ahi tuna) were accurately labeled through independent genetic identification.
“This is an important study in that it provides consumers with critical knowledge about the safety of food products that otherwise seem like healthy snacks,” says Mr. Brown. “Parents, in particular, need to know whether or not toxic substances are potentially present in foods they may be considering to give to their children.
Their results showed that marlin jerky contained the most dangerous concentrations at 5 parts per million mercury, more than five times the limit of 1 part per million set by the U.S. Food and Drug Administration. Ahi tuna and salmon jerky contained mercury levels as high as 0.5 parts per million mercury.
A 132-pound person eating a small 1.5 ounce bag of marlin jerky at the average mercury concentration would result in an intake of mercury five times the weekly limit deemed safe by the FDA, says Mr. Brown. A total of 105 fish jerky samples were tested from 21 packages purchased at stores in Hawaii and California and from on-line vendors.
Other highlights of the study include:
- Only one package of marlin jerky had all five samples below the FDA level of 1 part per million
- Six marlin jerky samples contained mercury greater than 10 parts per million
- One marlin sample reached 28 parts per million
- Most of the marlin samples (89 percent) exceeded the lower U.S. Environmental Protection Agency action level of 0.5 parts per million mercury
- The 15 samples of ahi tuna had mercury concentrations ranging from 0.09-0.55 parts per million mercury
- Mercury concentrations in 15 salmon samples ranged from 0.030-0.17 parts per million mercury
Like other large, long-lived fish, mercury accumulates in the flesh of marlin, a commercial and prized sport fish. When dried for jerky, mercury levels become concentrated. Marlin jerky and other fish jerky are sold at supermarkets around the U.S. and online and often marketed as a healthy food choice.
According to the U.S. Environmental Protection Agency, the number-one source of mercury exposure in the United States is contaminated seafood. Mercury ingestion can lead to memory loss, developmental and learning disorders, vision loss, heart disease and, rarely, death.