Clamoring for safe seafood

Washington hostess tells the story of an acquaintance who summarily declined her dinner invitation when told the entree would be grilled trout. The would-be guest objected on grounds that most trout sold these days is farm-raised, and he believes the health of such fish is harmed by what they are being fed.

Call the problem fish phobia or, alternately, the seafood scare. There is a great deal of confusion among consumers about the general health of various species of fish and conflicting advice about the best sources of information on the subject.

What may be considered a safe fish to eat in one location — free of pollutants and of population pressures — may not be in another. Though numerous authorities and organizations are qualified to speak out on the subject, their studies are not always conclusive. The world of aquaculture is vast and still in its infancy.

Fish often is touted as an excellent source of protein and a good choice because it is low in the kinds of fat that most often lead to heart disease. Salmon is one of the species known to contain a large amount of beneficial omega-3 fatty acids found in all fish. Omega-3 fats also are found in algae and other plant sources, says Wahida Karmally, a research scientist and registered dietitian who teaches at Columbia University.

Not all so-called fish farms can be maligned categorically, although some farms may use feed that has a high concentration of mercury and polychlorinated biphenyls, or PCBs. The latter is a toxic chemical, now banned, that seeps into the soil from various waste products and is known to have long-term health effects on humans. Long-term exposure to mercury can severely harm body organs.

Rob Klink, executive chef of Oceanaire Seafood Room in Northwest, says the secret to getting healthy, uncontaminated fish is knowing your suppliers and vendors and paying attention to ongoing research. He cites a study in the October issue of Science magazine that states that mercury found in fish is less toxic than that from other sources.

“The Food and Drug Administration and the Environmental Protection Agency are working on this matter,” he notes.

Most salmon served in Mr. Klink’s restaurant is wild because, he says, wild salmon is known to be less contaminated. It generally is more expensive than farm-raised salmon because of the costs involved in capture and shipment of the fish, but a restaurateur can’t take salmon off the menu because customers demand it, he and other chefs report.

“All fish have a trace of mercury because it is in their makeup,” Mr. Klink says. “Mercury mainly can be found in migratory fish, such as shark, sword, king mackerel, tilefish and occasionally tuna, but the amount depends on the age of the fish and when it is caught.”

Larger predatory species, the ones higher up on the food chain, travel great distances and prey on smaller fish, which means they have more opportunity to consume more pollutants.

Shellfish such as shrimp and scallops are scavengers that tend to be close to the bottom of the sea, so they are less contaminated by pollutants. Halibut, which has a low level of toxic residue, also is a bottom feeder and doesn’t prey on larger fish.

Mrs. Karmally warns consumers to be sure to clean shellfish well and to remove the dark vein on the back of shrimp before eating. “As scavengers they pick up all the dirt,” she says.

“I think all fish are OK in moderate portions,” she says. “Just don’t eat the same food every day. And you don’t have to eat eight ounces of fish. Three ounces is sufficient, a small fillet no larger than a pack of [playing] cards.”

Story Continues →