Hazard of mercury in fish debated
Written by Times Leader   
Tuesday, 27 December 2005 11:40

Shipped from Singapore, the swordfish entered the United States this year without being tested for the toxic metal mercury. When a fillet from that fish reached a display case at a supermarket in Illinois, it carried no government warning labels, even though federal officials know swordfish often is so contaminated that young children and pregnant women should never eat it.

And when the Chicago Tribune bought and tested this particular piece of fish, the results showed not just high amounts of mercury, but levels three times the legal limit.

This repeated neglect by the U.S. government — the lack of mercury testing, the failure to adequately warn consumers, the unwillingness to enforce its own rules — has unnecessarily put Americans at risk for decades, a Chicago Tribune investigation shows.

Year after year, the federal government has failed to fully disclose the hazards of mercury in fish to the public.

In some cases, regulators have ignored the advice of their own scientists who concluded that mercury was far more dangerous than what consumers were being told.

In other instances, regulators have made decisions that benefited the fishing industry at the expense of public health.

Even though mercury can cause learning disabilities in children and neurological problems in adults, regulators do not even bother to routinely check fish for the metal. This leaves consumers with little idea of which fish are most hazardous.

While regulators have issued numerous warnings for fish caught recreationally, they have rarely done so for seafood sold in supermarkets, where most people buy their fish.

The U.S. government’s only guide for consumers — a mercury warning posted on federal Web sites but not required in stores — is so flawed and misleading that people following the advice still could expose themselves to too much of the toxic metal.

The Food and Drug Administration, the agency responsible for the safety of commercial seafood, does not dispute recent studies showing that consumers might be harmed by relatively low levels of mercury. But the government’s permissible mercury limit in fish has remained the same for 25 years.

That limit remains one of the weakest in the Western world. For example, fish sold in America is allowed to have twice as much mercury as seafood sold in Canada.

The American "standard reflects the science of the 1970s," said Kathryn Mahaffey, a scientist at the U.S. Environmental Protection Agency and co-author of a report to Congress on mercury. "The science has changed, but the standard hasn’t changed with the science."

In a series of interviews with the Chicago Tribune, the FDA defended its handling of the mercury issue, saying its decisions are based on the best scientific evidence available at the time.

"Am I pleased with the way our department has handled this issue? Yes," said David Acheson, the FDA’s chief medical officer. "Outstanding job."

Acheson noted that the agency does not want to scare people away from eating fish because seafood is a low-fat source of protein and offers many other health benefits.

The FDA has a limited budget, he said, making it difficult to regularly inspect fish at ports or supermarkets for mercury contamination — or even to enforce the agency’s own rules.

"Going out and using our resources to test individual fish, with the goal of protecting public health, is not a good use of our tax dollars," Acheson said. The agency is well aware, he said, that some species contain high levels of mercury and has tested enough of those fish to decide how best to protect the public.

But Acheson acknowledged more testing is needed for certain kinds of fish. The agency is taking 15 samples each of 29 species of fish this year to address the lack of information, he said.

The FDA’s main strategy to protect consumers from mercury has been to issue warnings, though those advisories have been criticized as inadequate.

Last year, the FDA and the EPA jointly warned pregnant women, nursing mothers, women of childbearing age and young children not to eat shark, swordfish, king mackerel and tilefish because of high mercury levels. The warning also cautioned those groups to consume no more than 12 ounces of fish a week, including no more than 6 ounces of canned albacore tuna.

But a former senior EPA toxicologist said the advice fails to reflect the government’s own calculations about how much fish — and what kinds of fish — people can safely eat each week.

The warning "was not based on science," said Deborah Rice, who helped develop the government’s mercury exposure limit for the EPA.

In recent interviews, the FDA said it had no immediate plans to start routine testing of fish, improve warnings or re-evaluate its mercury limit.

Many who have closely followed the issue said the FDA’s outreach has been tepid at best. Michael Shannon, a pediatrician at Children’s Hospital in Boston who sat on a panel that advised the agency on its recent mercury warnings, questioned whether the government has effectively informed the public.

A lack of government guidance makes it difficult to avoid mercury in seafood. But consumers can take steps to reduce the likelihood of eating tainted fish.

While it makes no difference where you shop — supermarkets, health food stores and gourmet fish shops often use the same suppliers — consumers can choose to buy certain kinds of seafood.

Small or short-lived species, such as sardines, shrimp, crab and tilapia, generally have low amounts of mercury. Wild salmon, which eat plankton and small fish, are low in mercury, as are farm-raised salmon, which are fed fish meal containing little mercury.

Large predator fish, such as swordfish and shark, generally have the most mercury.

Regulators report that fish sticks and fast-food fish sandwiches, which typically are made with pollock, are low in mercury. But scientists say more tests are needed to confirm that.

Cooking does not remove mercury from fish because the metal is bound to the meat. For example, a piece of tuna will have the same amount of mercury whether it is eaten raw as sushi or cooked on the grill.

Although some mercury is present in all bodies of water, the nation’s drinking water generally is not considered a mercury hazard; federal law requires drinking water be tested and treated to remove the toxic metal.

For consumers shopping for fish, money offers no protection against mercury exposure. Rutgers University scientist Joanna Burger recently compared fish bought at stores in wealthy New Jersey areas with those bought in poor ones. She found no differences in mercury levels.

"They were mainly getting their fish from the same source," said Burger.

People concerned about exposure to mercury because of the fish they eat should consult a doctor. Blood and hair tests can determine a person’s mercury levels

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