Toxins Cited in Farmed Salmon

Cancer Risk Is Lower in Wild Fish, Study Reports

By Eric. Pianin Washington Post Staff Writer

Friday, January 9, 2004; Page AO1

Farm-raised salmon, a growing staple of American diets, contains significantly higher concentrations of PCBs, dioxin and other cancer-causing contaminants than salmon caught in the wild, and should be eaten infrequently, according to a new study of commercial fish sold in North America, South America and Europe.

The study, using Environmental Protection Agency health guidelines, concluded that although consumers can safely eat four to eight meals of wild salmon a month, consumption of more than one eight-ounce portion of farmed salmon a month in most cases poses an "unacceptable cancer risk."

Food and Drug Administration and fishing industry officials immediately took issue with the findings. They said the contaminant levels in salmon have declined by 90 percent since the 1970s, and that the remaining threat - when balanced against the high protein and cardiovascular health benefits of eating salmon—do not warrant shunning the food.

"We've looked at the levels found . . . and they do not represent a health concern,' said Terry C. Troxell, director of the FDA's Office of Plant and Dairy Foods and Beverages. "In the end, our advice is not to alter consumption of farmed or wild salmon."

The two-year, $2.4 million study, funded by the Pew Charitable Trust and published yesterday in the journal Science, is the latest blow to the commercial fish industry, already suffering from growing concerns about elevated levels of mercury in tuna and shellfish.

The study found that salmon contamination varied by geography. Store-bought samples from Frankfurt, Edinburgh, Paris, London and Oslo were generally the most contaminated, while samples from stores in New Orleans and Denver were the least.  Cities including Washington, New York, Los Angeles, Chicago and Seattle ranked somewhere in the middle, and their residents were advised to eat farmed salmon no more than once or twice a month.

EPA guidelines say that if a person eats fish twice a week, it should contain no more than 4 to 6 parts per billion of PCBs. The study found that PCB levels in farmed salmon sold in the United States and Canada averaged about five times that amount: 30 parts per billion. On average, farmed salmon had concentrations of health threatening contaminants 10 times as high as those found in wild salmon.

Consumers may have difficulty distinguishing between farmed and wild salmon, because many stores and restaurants do not clearly label them. Wild salmon is three to four times as expensive, but some retailers confuse the issue by identifying farmed salmon as "Atlantic salmon." The study called for labels differentiating wild from farmed and noting the country of origin.

Ninety percent of the fresh salmon consumed in the United States is farm-raised, industry of finials say. More than half of that salmon comes from Chile, however, where the pollutant level of farmed salmon is less than that of most other regions but still higher than in wild fish, according to the study.

Farmed fish contain higher concentrations of contaminants than wild fish largely because they are fed meal that consists of ground-up fish tainted with the contaminants. Wild salmon eat tiny fish and aquatic organisms that are less contaminated

Salmon of the Americas, a group representing producers of farmed salmon in the United States, Canada and Chile, described salmon as an unparalleled source of omega-3 fatty acids for prevention of coronary heart disease and noted that contaminant levels for North and South American wild and farmed salmon are well below FDA and World Health Organization limits. Alex Trent, executive director of Salmon of the Americas, said his industry does not discount some of the health problems associated with PCB contamination of farmed salmon. But meat and dairy products consumed in large quantities pose similar problems, he said, and consumers would be foolish to deny themselves the health benefits of salmon.

" Scaring people away from farm salmon presents more of a health risk than letting them eat PCBs at these trace levels," Trent said.

But the study's chief author said the FDA consumer health guidelines for eating salmon need to be updated.

"We are not saying people shouldn't eat farmed salmon," said David O. Carpenter, director of the Institute for Health and the Environment at the State University of New York's University at Albany and chief author of the study. "We're telling them to reduce their frequency of consumption until the industry can develop a food source for omega-3 fatty acids that does not have these contaminants. "

Diet- and health-conscious Americans have turned to salmon in recent years, and about 23 million eat the fish more than once a month The annual global production of farmed salmon has increased fourfold in two decades.

Some producers of farmed fish have taken steps to improve the quality of the meal fed to their fish, although critics say far more needs to be done to eliminate PCBs and other contaminants.

PCBs, or polychlorinated biphenyls, have been banned in the United States since the late 1970s and are among a dozen chemical contaminants targeted for worldwide phaseout under a U.N. treaty. PCBs, which were used as industrial insulators, persist in the environment and have been linked to cancer and impaired fetal brain development. Dioxins, a byproduct of high-temperature industrial and waste treatment, have been linked to cancer, reproductive and developmental problems and altered immune functions.

Jane Houlihan, vice president for research at the Environmental Working Group, said the study "leaves little room for the farmed fish industry to argue away the problems of polluted farmed seafood."

But Mike Bolger, director of FDA's division of risk assessment, said his agency is identifying sources of PCBs and other dioxin-like contaminants in fish and working with the industry on ways to reduce their presence in salmon feed. "We're convinced [this is] the most effective, efficient and quickest way of reducing exposure," he said.

~ 2004 The Washington Post Company