An investigation of tuna served in Chicago sushi restaurants adds to a recent stream of bad news about high levels of mercury in store bought tuna, locally-caught sport fish and other seafood available to Illinoisans. Fourteen of 20 tuna sushi samples tested, or 70 percent, exceeded Illinois EPA’s special advisory threshold—the mercury contamination level at which the agency recommends women and children eat no more than one serving of fish per month. More than one in seven sushi tuna samples contained dangerous concentrations of mercury exceeding that of king mackerel, which the U.S. Food and Drug Administration (FDA) warns women and children never to eat.
“Governments should require advisories to be posted in restaurants and stores where tuna is sold,” said Eli Saddler, public health analyst for GotMercury.Org. “Mercury advisory signs will educate Illinois families about mercury risks. Tuna sold as sushi, sashimi, and `ahi are consistently high in mercury and women should avoid it for the sake of their children—especially pregnant or nursing mothers or women who intend to become pregnant. With healthier seafood choices like wild salmon or tilapia available, why take the risk?"
"Mercury contamination is a toxic threat to food safety in Illinois. While building consumer awareness is imperative in the short term, the only long-term solution is to cut off mercury pollution at its source,” said Max Muller, Environmental Advocate for Environment Illinois. “In Illinois, the main sources are coal burning power plants and the improper disposal of products containing mercury. Whether it’s locally caught sport fish, canned tuna, or fresh tuna in sushi rolls, recent revelations of mercury contamination in fish in Illinois highlight the need to clean up mercury pollution as much as possible and as soon as possible.”
The health harms of mercury are well known: mercury is a potent neurotoxin that accumulates in animals and the environment. Fetuses and young children are particularly vulnerable as mercury poisons the developing brain, causing delayed development, memory and attention problems, decreased IQ and mental retardation. Higher doses similarly impair adults and can also increase the risk of heart attacks. It is estimated that up to 100,000 Illinois women have sufficiently high blood-mercury levels to put an unborn child at risk of developmental problems. People get most of their mercury from eating fish—and now tuna sushi, like canned tuna and many local sport fish, has been shown to be contaminated with too much mercury to be eaten safely on a regular basis.
For the report, Environment Illinois teamed up with GotMercury.Org to collect and test twenty samples of tuna sushi from ten of Chicago’s top sushi restaurants selected from the popular Zagat Survey dining guide. Findings detailed in the full report, Toxic Tuna, include that Chicago tuna sushi samples contained an average mercury concentration of 0.446 ppm—about 15 percent higher than the mercury content (0.383 ppm) of fresh and frozen tuna reported by the U.S. Food and Drug Administration (FDA). Based on reports showing varying levels of mercury in canned tuna, including supposedly lower mercury canned light tuna, the Consumer Union, the publisher of Consumer Reports, recommended in July that pregnant women avoid eating all tuna.
Moreover, the Toxic Tuna analysis showed high variability in mercury among the tested samples, with more than 10% of the tuna samples contained levels of mercury that shouldn’t be eaten by any consumer—man, woman, or child—because they exceed the FDA’s “actionable level” of mercury (1.0 ppm). The actionable level is the legal limit for fish sold in the United States; when fish exceed the actionable level, the FDA can remove them from store shelves because of the health threat posed.
“Without better FDA action to protect public health, consumers need to be able to make informed decisions about healthier seafood choices. The easiest and cheapest way is through posting mercury advisories,” said Saddler. “Consumers will continue to eat sushi and fish when provided the government advisories. Mandatory mercury advisories in California have not harmed businesses, but have helped families protect themselves. In fact, seafood consumption is at an all-time high according to the federal government.”
“The health effects of mercury are well established. These findings should steer women away from this sushi,” said Dr. Peter Orris, Professor and Chief of Environmental and Occupational Medicine at the University of Illinois Medical Center. “Mercury contamination is a serious social issue, even for women who are only considering getting pregnant. Exposure of the fetus is dangerous, but all too frequent, and its impacts in all likelihood burden both our education and health care systems. If we fail to reduce the sources of this pollution, personal tragedies and yearly billions in costs to society will continue to mount.”
Illinois has been the site of several recent revelations about dangerous levels of mercury in fish. In December, the Chicago Tribune broke a nationally reported news story revealing U.S. EPA and FDA’s failure to systematically monitor and warn consumers about mercury in canned tuna and other fish available in stores. In April, Environment Illinois issued a report showing that the average sport fish tested in 36 Illinois counties, 66 individual lakes and streams, and 16 fish species exceeds the U.S. EPA safe limit for a woman of average weight who eats fish twice per week.
Illinois policy makers have responded with proposals to notify consumers and prevent mercury pollution at the local, state, and national levels. An Illinois EPA rule to reduce mercury emissions from coal-fired power plants will likely come before a legislative committee for final approval in October. In July, Illinois Senator Barrack Obama introduced two bills in Congress to prohibit the export of mercury and phase out its use in certain industrial processes. State Representative Harry Osterman and Chicago Alderman Ed Burke have championed initiatives to require the labeling of mercury-containing fish in grocery stores. However, aside from a bill sponsored last session by State Representative Karen May to recycle mercury-containing automobile switches, none of these measures has yet been adopted.
"Illinois is making progress in eliminating this dangerous toxin from our environment, but there is still a tremendous amount of work to be done," said Representative May (D-Highland Park). "Until we curtail all major sources of mercury pollution, we are knowingly endangering the healthy development of Illinois children. I along with other Illinois leaders have proposed common sense steps to significantly reduce mercury pollution locally, nationally, and globally. This report proves that we need redouble our efforts to protect Illinoisans.”