Limits Urged on Eating Tuna
U.S. Agencies Cite Levels of Mercury
By Marc Kaufman
Washington Post Staff Writer
Saturday, March 20, 2004; Page A01
For the first time, the federal government has warned pregnant and nursing women and young children away from eating more than a limited amount of canned albacore "white" tuna because of potential hazards from mercury in the fish.
Responding to research that showed concentrations of mercury are significantly higher in the larger albacore species than in the smaller skipjack, or "chunk light" tuna, the government advised potentially vulnerable consumers yesterday to eat no more than six ounces of albacore tuna per week. That would amount to one meal.
The joint Food and Drug Administration and Environmental Protection Agency guidance also told women of childbearing age to avoid shark, swordfish, king mackerel and tilefish because of high mercury levels.
The recommendation regarding tuna was immediately attacked as inadequate by a member of the FDA advisory panel that addressed it. University of Arizona toxicology professor Vas Aposhian resigned from the panel, saying the advisory did not reflect the experts' view that children and childbearing women should not eat albacore tuna, and should eat less light tuna than the advisory recommends.
"We wanted albacore on the list of fish not to eat," Aposhian said. "We knew that wouldn't happen because of the pressure from the industry, but we certainly didn't think there should be a recommendation to eat six ounces of albacore."
Mercury comes from industrial pollution that gets into water and then the food supply, and builds to potentially hazardous levels in larger fish. Even in trace amounts, mercury, a toxin, can cause neurological and developmental problems in infants and young children.
Tuna is the second most popular seafood in the United States. The issue of whether children and childbearing women should be warned away from it has been hotly debated.
The tuna industry has generally resisted the warning and questioned the scientific findings underlying it, and some consumer and environmental groups have pressed for stronger action. One organization, the Environmental Working Group, has filed an official regulatory challenge to the FDA advisory.
Complicating the question of whether vulnerable consumers should be warned away from tuna is that researchers have identified especially high-quality proteins and nutrients in tuna and other fish. Some of the proteins are important for brain development.
The federal agencies issued the advisory about albacore tuna (which is generally more expensive) while also listing low-mercury fish that can be eaten more frequently -- including shrimp, canned "light" tuna, salmon, pollock and catfish. The advisory recommended eating as much as 12 ounces (or two average meals) of these fish per week. According to the FDA, fish sticks are largely made from pollock.
"By following this advice, we're confident that women and young children can safely include fish as an important part of a healthy diet," said the FDA's acting commissioner, Lester M. Crawford.
The potential danger from eating tuna is limited to children and women who are, or may soon be, pregnant, because mercury in very low amounts is harmful only in early years of development. According to David W.K. Acheson, chief medical coordinator for the FDA's Center for Food Safety and Applied Nutrition, the possible harm from mercury in fish is not changed by whether, or how, the fish is cooked.
In a release, the U.S. Tuna Foundation, which represents much of the industry, emphasized the positive message from the federal agencies -- that eating fish has many benefits, and that even women of childbearing age and youngsters can safely eat some.
"By advising pregnant women and nursing mothers to eat a variety of different species of seafood a week, the government's advisory also makes it clear that pregnant and nursing women can safely consume albacore as one of their fish choices," the foundation wrote. "The new advisory tells pregnant women they can safely eat up to six ounces of albacore a week (an average sandwich contains 2 ounces)."
The foundation said that about 78 percent of tuna sold in the United States is the lower-mercury "chunk light" variety of skipjack tuna. "Solid white" albacore makes up about 22 percent of the $1.3 billion domestic tuna market. The albacore variety, which foundation officials say can always be identified by labels on the can, may have three times as much mercury -- because the fish are older and have consumed more from the environment.
The new advisory recommends similar restrictions on tuna steaks, which are also from larger fish and so are in the higher-mercury category.
Coal-fired power plants are the greatest single source of mercury in the environment. Emissions from the plants drift into lakes and streams, where they are transformed by bacteria into methylmercury. Fish aborb the methylmercury, then are eaten by larger and larger fish -- ending with deep-sea fish such as tuna and swordfish.
The Clinton administration proposed rules to limit mercury emissions by 2007. The Bush administration has pushed back the deadline to begin cutting mercury emissions to 2010.
Yesterday's fish advisory was sharply criticized by the Environmental Working Group, a nonprofit group of environmental investigators. It has challenged the FDA, saying the agency is withholding information regarding mercury in seafood and misusing the scientific data it has.
"The coal and seafood industries' interests today beat out the health interests of America's children in the form of dangerous advice from the FDA on so-called 'safe' consumption levels for fish contaminated with mercury, particularly tuna," senior vice president Richard Wiles said in a release.