Great Lakes Article:

Know the history of your fish
By David Steinkraus
The Journal Times
01/10/04

Study finds more contaminants in farm-raised salmon

Before you lift that forkful of salmon to your mouth and savor the health benefits of fish oil, you would do well to ask where that fish came from.

In a study published today in Science magazine, a group of researchers write that farm-raised salmon had higher concentrations of contaminants than their cousins caught in the wild - up to 10 times as much. How much contamination farm-raised fish contain also depends on where they were raised, the authors say.

Fish from Scotland and the Faroe Islands had the highest concentrations of contaminants such as dioxins and PCBs, the authors write. Those from northern Europe also had significant concentrations, while fish with the lowest concentrations came from Chile and Washington state, the study says.

None of the concentrations, measured in parts per billion, exceeded U.S. Food and Drug Administration standards, although those are not strictly health-based, the authors wrote.

"Most of the salmon that we sell come from Chile," said Mike Collier, sales manager at Houmann's Fish & Seafood in Racine.

The company - which sells fish wholesale to area restaurants and stores as well as at its retail counter - carries wild Alaskan salmon when it's available and also sells farm-raised Norwegian salmon in addition to the farm-raised Chilean salmon, he said. "Some people we have to bring

(Norwegian fish) in special for." Some people say cold-water fish are better, he said.

Fish farming has drastically cut seafood prices, Collier said, and made fish available year-round, which is not the case with Alaskan salmon caught by commercial fishermen. Even supermarkets now carry salmon, he said. "Years ago they couldn't even buy it because it was so expensive." Salmon that sold for $7.95 a pound 15 years ago can now be bought for $3.95 a pound, he said.

The Science study notes that global salmon farm production has increased from about 26,000 tons to about 1 million tons during the past 20 years.

Don't quit "We are not in the business of giving consumption advice to people, except to say that people should not stop eating fish, and that's a very important message," said Jeffery Foran, one of the co-authors of the study. "Fish are good for you. We think this study encourages fish consumption, but in an informed way that also allows reduction of exposure to contaminants."

Foran, who holds a Ph.D. in toxicology, is president of Citizens for a Better Environment in Milwaukee and is also an adjunct faculty member at the University of Michigan.

The Science magazine study doesn't address the question of whether the benefits from eating fish are outweighed by the risk from any contaminants. That's work for the future, Foran said.

"But what's absolutely clear from this study is that the farmed salmon, no matter where they come from, have higher concentrations of these contaminants than the wild salmon."

A preliminary comparison of his group's results with other information suggests that fish from Lake Michigan carry higher concentrations of contaminants than the farm-raised fish, Foran said.

Food chain Contaminants most likely reached the farmed fish through their feed, Foran said. "It has to be the feed. And these fish don't go out and eat other fish."

Chemicals such as PCBs are concentrated in industrialized areas from decades of chemical use, and are blown into the water, or flow into it through rivers, just as in the Great Lakes, he said.

Farmed fish are given food pellets made from other fish caught in the ocean, presumably near the fish farms, he said. "They've concentrated three levels of the food chain in a pellet, and so you get the biomagnification, the bioconcentration, when you make the pellet. And then you give it to the fish, of course, in large doses because they want these fish to grow very rapidly."

The group didn't completely follow this line of investigation, so that conclusion about feed is somewhat speculative.

Although the researchers looked at some 700 fish purchased through brokers and from stores in Europe and North and South America, it's not good to analyze the results too closely, Foran said. There is great variability individual fish, he said, so what you need to remember is the trend - that wild fish are generally less contaminated than farm-raised fish.