Recently released data from FDA indicate that 6% of samples taken from canned light tuna between 2001 and 2005 contained high levels of mercury, which can increase risks of health problems in pregnant women and children, the Chicago Tribune reports (Roe/Hawthorne, Chicago Tribune, 1/27). High levels of mercury -- which accumulates in the environment, as well as in the flesh of fish and the bodies of those who eat fish -- have been shown to contribute to birth defects and other health problems, and several studies have demonstrated a subtle loss of mental acuity in the offspring of women who consume fish during pregnancy. FDA and Environmental Protection Agency warnings issued in 2005 advise young children, pregnant women, nursing mothers and women of childbearing age to avoid consuming swordfish, king mackerel, shark and tilefish because of high mercury levels. The warning also recommends that those groups eat no more than 12 ounces of fish weekly and eat no more than six ounces of canned albacore tuna weekly (Kaiser Daily Women's Health Policy Report, 1/23). For the recent data, FDA looked at 216 samples of canned light tuna and found the average mercury levels to be 0.12 parts per million, which is below the legal limit of 1.0 parts per million. Twelve of the samples contained 0.35 parts per million, which also is legal but considered high by government standards. According to the Tribune, high levels also were found in samples of Chilean sea bass and big-eye tuna, also known as ahi tuna. The Tribune reports that no federal warnings exist for either fish. FDA on Thursday said it does not plan to take any action based on the new data.

Questioning the Process
Some experts have questioned FDA's data-gathering process. According to the Tribune, FDA tested a mixture of samples from 12 cans of tuna during the study instead of testing individual cans. An unnamed FDA official said, "It would cost 12 times as much to test 12 separate cans and then average the data, which is what we would have to do." During the testing, one sample's mercury levels were recorded at 0.72 parts per million, which might indicate some of the samples in the mixture contained higher levels, according to the Tribune. Jane Hightower, a San Francisco-based internist who treats patients with mercury-related conditions, called the process "incredibly disturbing," adding, "That is falsifying data as far as I am concerned" (Chicago Tribune, 1/27).