Mercury and Fatty Acids in Canned Tuna, Salmon, and Mackerel

The Scientific Paper:

S.M. Shim, L. E. Dorworth; J.A. Lasrado, and C.R. Santerre. Journal of Food Science. Vol. 69, No. 9. pp. 681-684. 2004.

Review This Scientific Paper’s Abstract:
http://www.cfse.purdue.edu/files/news/MercuryFattyAcidsCanned.pdf

The Purpose of this Study:
To determine the concentrations of methylmercury and certain beneficial fatty acids in canned tuna, salmon, and mackerel.

These scientists are attempting to learn what amounts of commonly consumed fish pregnant women - or women who may become pregnant – can eat to limit their intake of methylmercury while obtaining certain beneficial fatty acids from fish.

Some Background, Methods, Results, Caveats, and Other Select Points:

• This peer-reviewed, scientific paper was published in 2004.
• These scientists studied far fewer samples of fish than did the Food and Drug Administration (FDA) in its fish sampling and testing program for methylmercury and certain beneficial fatty acids in fish.
• The Food and Drug Administration (FDA) regulates methylmercury in fish and shellfish sold in interstate commerce.
• A typical can of white / albacore tuna has a net weight of 6 ounces or 170 grams.
• Light tuna in water contained less methylmercury compared with white / albacore tuna in water. However, white / albacore tuna in water contained more of some of the certain beneficial fatty acids than did light tuna in water.
• Methylmercury and some of the certain beneficial fatty acids in the samples of canned tuna studied by these scientists varied with type of tuna and how it was packaged.
• A person weighing about 130 pounds who ate about 20 grams (or 0.7 ounces) of canned tuna every day would be exposed to less methylmercury than the limit recommended in 2004 by the Environmental Protection Agency (EPA). This amount of white / albacore tuna would provide sufficient amount of some of the certain beneficial fatty acids found in fish.
• The scientists purchased 5 brands of canned tuna, 2 brands of canned salmon and 2 brands of canned mackerel from local stores in Lafayette, Indiana in 2003 for a total of 272 cans. From each lot, the total contents of 2 cans were combined and ground in a food processor to obtain a single uniform sample. One gram of each of these uniform samples was analyzed in duplicate for total methylmercury using a series of testing instruments.
• For determination of total fat, these samples were randomly chosen from each lot, thawed, and mixed well. A special, modified testing method was used to determine total fat concentration.
• These scientists support the concept of a kid-safe label for light tuna in water because they found light tuna in water contains less methylmercury.
• Pregnant and lactating women can get sufficient amounts of some of the certain beneficial fatty acids without exceeding the 2004 recommended limit of methylmercury by eating certain types of canned fish.
• These scientists reported that women of childbearing age who regularly eat a great amount of canned white / albacore tuna can get more than the recommended highest level of methylmercury.
• Methylmercury in canned fish did not exceed the Food and Drug Administration (FDA) methylmercury action level.

A Bottom Line:
These scientists found that the average methylmercury levels in the relatively few fish samples they studied were below the FDA methylmercury action level.

Based on this study, these scientists recommend that the FDA methylmercury action level in commercial fish should be more restrictive – or – that fish sold exceeding this level should carry an appropriate methylmercury warning.

Find This Scientific Paper for Your Review:
Mercury and Fatty Acids in Canned Tuna, Salmon, and Mackerel. Journal of Food Science. Vol. 69, No. 9. pp. 681-684. 2004.