High Levels of Mercury Found in Fish Jerky
SAN FRANCISCO, California, October 14, 2011 (ENS) – Mercury levels in marlin, ahi tuna and salmon fish jerky average five times the U.S. government allowable levels, according to new research published in the current issue of the “Journal of Environmental Health.” The scientists found one marlin sample that tested at 28 times the allowable level of one part per million.
Like other large, long-lived fish, mercury bioaccumulates in the flesh of marlin, a commercial sport fish. When dried for jerky, mercury levels become concentrated.
Marlin jerky and other fish jerky are sold at supermarkets around the United States and online and often marketed as a healthy food choice.
Because omega-3 fatty acids in fish are recognized as having antioxidant and anti-inflammatory properties beneficial for good health, many consumers are looking to fish as their main source of protein. But contaminants such as methylmercury can accumulate in larger species of fish.
Fish jerky (Photo by Kathleen Devon)
Mercury contamination of seafood is a widespread public health problem, especially for women of childbearing age, pregnant and nursing women and children. Mercury ingestion can lead to memory loss, developmental and learning disorders, vision loss, heart disease and, rarely, death.
The purpose of this research was to test commercially available fish jerky snack foods for mercury contamination.
The research was conducted by physician Dr. Jane Hightower, also the author of the book, “Diagnosis Mercury.” Dr. Hightower specializes in internal medicine at the California Pacific Medical Center located in San Francisco.
The study was co-authored by Dr. David Brown of Chico State University.
For the research, 15 bags of marlin jerky, three bags of ahi tuna jerky, and three bags of salmon jerky were purchased from large retail stores in Hawaii and California, and directly from the proprietors’ websites.
Five individual strips of jerky per bag were analyzed for a total of 105 tests.
The study found that only one package of marlin jerky had all five samples below the U.S. Food and Drug Administration level of one part per million. The FDA is responsible for seafood safety and the regulation of mercury in commercial fish and fisheries products.
The researchers found one marlin sample that tested at 28 parts per million.
Six marlin jerky samples contained mercury greater than 10 parts per million, the researchers found.
Most of the marlin samples, 89 percent, exceeded the lower U.S. Environmental Protection Agency action level of .5 parts per million of mercury.
The 15 samples of ahi tuna had mercury concentrations ranging from 0.09 to 0.55 parts per million mercury.
Mercury concentrations in 15 salmon samples ranged from 0.030 to 0.17 parts per million mercury.
The Food and Drug Administration has never tested mercury in fish jerky, so it is not included in the agency’s advisory for women and children not to eat high mercury fish such as swordfish and shark and to limit servings of albacore tuna.
“It is shocking to find such high levels of toxic mercury in a snack sold as a healthy food,” said Teri Shore of GotMercury.org, a public health advocacy based in Marin County, California, that provides a free online calculator for estimating mercury exposure from fish.
“Mercury warnings need to go on fish jerky labels so people can make informed choices,” said Shore. “The federal government must take immediate action to alert people to this hidden mercury threat.”
Marlin jerky contained the most dangerous concentrations at an average of five parts per million mercury, more than five times the limit of one part per million set by the U.S. Food and Drug Administration.
Ahi tuna and salmon jerky contained mercury levels as high as .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 Food and Drug Administration.
According to the U.S. EPA, the top source of mercury exposure in the United States is contaminated seafood. The FDA has determined that women of childbearing age and young children should not eat swordfish and should limit consumption of tuna due to high mercury levels.