Good catches: concerned about fish contamination? Here's how to enjoy this healthy seafood safely.(FOOD: EAT SMART)

Eating fish has never been so popular, with customers crowding local seafood counters and exotic fish filling restaurant menus. In 2004, the average American consumed 16.6 pounds annually--up 8 percent since 1999, says the National Marine Fisheries Service.

Officials at the American Heart Association recommend at least two servings a week, emphasizing fatty fish such as lake trout and salmon, rich in the omega-3 fatty acids associated with heart health. But there's a significant catch--at least for some consumers.

Nearly all fish are contaminated to some degree with mercury and other toxic chemicals, such as polychlorinated biphenyls (PCBs). In 2004, officials at the Environmental Protection Agency (EPA) and the Food and Drag Administration advised young children and pregnant or nursing women to avoid swordfish and other large predatory fish more likely to carry significant mercury, and to limit total fish consumption to two meals weekly.

Fish or Cut Bait?

Fish industry advocates and some researchers worry that too much emphasis on contaminants will unnecessarily spook numerous other Americans from eating fish. "If people are scared away because of the mercury, their health will be a lot worse off than that of someone who eats fish and has low-level exposure to mercury and other contaminants," says Charles Santerre, PhD, a longtime fish researcher and a food toxicology professor at Purdue University.

Neither is the contaminant research universally conclusive. A 15-year, ongoing University of Rochester study that has tracked nearly 800 children in the Seychelles since birth has found no significant developmental delays despite the mothers' hefty fish consumption--an average of 11 to 12 fish meals weekly. (The average American's weekly intake is 5 ounces.) One explanation for these findings may be that beneficial fish nutrients offset mercury's toxic effects, says Phil Davidson, PhD, one of the study's researchers and an expert in developmental disabilities.

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