What did Schuler know that the FDA didn’t? For years, the agency has told pregnant women to avoid large, fatty fish such as swordfish and king mackerel, which carry heavy loads of methylmercury–a pollutant widely believed to harm fetal brains. Tuna tend to have slightly lower mercury levels. But the FDA draft guidelines reported last week counsel women to limit tuna intake to six ounces (one meal’s worth) per week if they’re nursing, pregnant, or even thinking about having a baby. They also note that tuna steaks and albacore contain more mercury than “light” tuna. It’s the first time the FDA has targeted tuna, and an unusually wide risk group for the agency to address. The guidelines, which go into effect next year, also advise the women to vary the other kinds of fish they eat, keeping total weekly intake below 12 ounces.
But pregnant women aren’t the only ones who eat tuna, and consumers of all types have become wary. In the past decade tuna sales have dropped 10 percent, to 2.3 billion cans per year, as mercury fears have seeped into the public consciousness. The White House’s new plan to loosen factory regulations–which opponents say will increase mercury pollution in the next 15 years–has brought the issue to the forefront as well. And a few studies have added to the alarm by linking low-level mercury exposure to heart attacks in adults. But other studies have found no link.
The scientific ambiguity–and the public panic–have become flash points for both sides. The Environmental Working Group wants the FDA to test more species and clarify the current tuna guidelines. Meanwhile, the U.S. Tuna Foundation’s David Burney says the studies are on his side. The amount of mercury in tuna is small, he says, and since there’s “absolutely no way to get it out,” the industry won’t change its practices. Women, on the other hand, just may change theirs.
