Farmed salmon is said to contain high PCB levels
By: Marian Burros
New York Times
30th July 2003
AMERICANS consume so much salmon these days - most of it farmed - that it is now the third most popular fish in the country, after canned tuna and shrimp. It is one of those foods that nutritionists say is good for you, and the Food and Drug Administration says you can eat as much of it as you like.
But a report released today by the Environmental Working Group, a nonprofit environmental research and advocacy organization, says that 10 samples of farmed salmon bought at markets on the East and West Coasts were found to be contaminated with PCB's, or polychlorinated biphenyls, at an average level far higher than any other protein source, including all other seafood. The high levels do not exceed those set in 1984 by the Food and Drug Administration for commercially sold fish. But they are in excess of the guidelines set by the Environmental Protection Agency in 1999 for recreationally caught fish. PCB's, an industrial byproduct, which has been identified as a probable human carcinogen, were banned by the United States in 1976.
The study has not been published in a peer-reviewed journal. But two previous peer-reviewed studies of farmed salmon found similarly high levels of PCB's. Responding to the fresh findings, Dr. Terry Troxell, a toxicologist in the F.D.A. centre for food safety and applied nutrition, said, "Any time we have a standard that goes back to the 70's and 80's, it's time to review it."
If consumers applied the findings to the environmental agency's 1999 guidelines, they might be wary of eating farmed salmon more than once a month. Farmed salmon accounts for 60 percent of the salmon consumed in the United States. The E.P.A. standards, which are far stricter than those used by the food and drug agency, are used by states to issue weekly consumption advisories for recreational fishing. For example, New York State says that wild striped bass caught in Jamaica Bay should be eaten no more than once a week, based on average levels of PCB's in the fish. One sample in the farmed salmon study contained levels of PCB's so high that the environmental agency's advice would be to eat it no more than once every two months. The remaining nine samples tested exceeded the agency's weekly recommendation. The salmon tested came from five countries, including Canada and the United States.
"Until we hear differently from the F.D.A., we would assume that theirs are the regulations we need to follow," said Alex Trent, acting director of Salmon of the Americas, an organization of 80 salmon farmers in the United States, Canada and Chile. "We assume they know what they are doing, and the regulations and levels they have promulgated mean that the food, including farmed salmon, is safe, wholesome and nutritious. E.P.A. and F.D.A. should work their differences out."
A high-level E.P.A. staff member said the environmental agency's recommendations "reflect the best science available to make recommendations to states for setting fish advisories.” The guidelines will continue to be used he said."
Kimberly Rawlings, a press officer for the Food and Drug Administration, said the F.D.A. was considering updating its guidelines. "We are clearly aware of it and actively looking at the science to see if the science dictates that it needs to be changed," she said.
The Environmental Working Group's study followed the analytical methods of the E.P.A., said Jane Houlihan, the group's research director. Each sample of farmed salmon, bought with its skin on, was cut into smaller pieces, ground up three times and mixed to homogenize the meat. A portion of the fish tissue was then extracted and analyzed for PCB's.
Three previous studies of farmed salmon found similarly high levels of PCB's: a study conducted at the University of Surrey in England of salmon bought in Scotland and Belgium and reported last year in the journal Environmental Science and Technology, which is peer-reviewed; a government study for the Food Safety Authority of Ireland, reported in March last year; and a study by Dr. Michael Easton of International EcoGenInc in British Columbia, reported last year in the journal Chemosphere, also peer-reviewed.
The Easton study, and the one from the Environmental Working Group, found the level of PCB's in farmed salmon in the United States and Canada 5 to 10 times higher than those in wild salmon. The average levels of PCB's in wild salmon, according to the Environmental Working Group report, are about 5 parts per billion; in farmed salmon, they are about 27 parts per billion, far below the F.D.A. levels of 2,000 parts per billion. Environmental Protection Administration guidelines say that if a person eats fish twice a week, it should contain no more than 4 to 6 parts per billion of PCB's.
The Environmental Working Group, based in Washington and financed by private foundations, used the seafood industry's fish consumption data to report how many Americans regularly eat salmon. About 25 percent of Americans eat salmon, they say; 23.1 million eat it more than once a month, 1.3 million people eat it once a week, and 180,000 eat it more than twice a week.
From those figures the organization conducted what it says is the first cancer risk assessment of exposure to PCB's from farmed salmon. The assessment estimates that 800,000 people face an increased lifetime cancer risk of more than one in 10,000 from eating farmed salmon, and 10.4 million people face an increased cancer risk exceeding one in 100,000.
Previous studies have shown that PCB levels in farmed salmon are higher than in wild salmon because of the fish meal they are fed. The meal, made mostly from ground small fish, has high levels of fish oil to fatten the salmon. PCB's concentrate in fats. An ounce of farmed salmon has 52 percent more fat than an ounce of wild salmon, the Department of Agriculture says. In June, the National Academy of Sciences called for changes in fish farming and in human consumption to reduce exposure to PCB's.
"When, and if, the F.D.A. changes its limits, we will be the first to comply," Mr. Trent said. "Someone is yelling fire in a theatre to help make their point, and they haven't proven this point to the F.D.A. yet. If they had, they would change their standards."
Wild Oats, a 100-store natural and organic supermarket chain, based in Boulder, Colo., is not waiting for the F.D.A. Starting next week, it will sell farmed organic salmon from the west coast of Ireland, which it says tests as low for PCB's as wild salmon because the company uses feed made of fish taken from clean waters within a 30-mile radius of its farm. The Irish salmon will sell for the same price as wild salmon, $10 to $11 a pound. Farmed salmon from Nova Scotia will continue to sell for $9 a pound.
Whole Foods Markets, a 145-store natural and organic foods supermarket based in Austin, Tex., is also looking for farmed salmon with lower levels of PCB's. Margaret Wittenberg, its vice president for public affairs, said: "The discrepancy between E.P.A. and F.D.A. is so dramatic one is hard pressed to make sense of it. F.D.A. should make this a high priority."