Tests Find High Mercury Levels in Fish

CHICAGO - Roughly a quarter of the fish bought at supermarkets and tested by a major newspaper contained mercury above the level the Environmental Protection Agency considers safe for children and pregnant women, the paper reported this week.

The testing, which sampled fish including swordfish, shark, tuna and orange roughy from stores in several states, found the highest levels in the predator species the FDA already warns about — but also found significant variation within species, including some canned albacore tuna that tested above the guideline.

Mercury, a metal released mainly by coal-fired power plants, accumulates in waterways and concentrates in the flesh of large, long-lived predatory fish. In developing brains it is a neurotoxin linked to learning deficits.

The FDA advises pregnant and nursing women and young children to avoid shark, swordfish, king mackerel and tilefish entirely and to limit albacore tuna — advice critics say is poorly publicized and rarely posted at the fish counter.

"The labels tell you the price per pound, not the mercury per serving," said a consumer advocate. "Most shoppers have never seen the advisory."

The seafood industry called the findings overstated, noting that fish remains a lean, heart-healthy protein and that the testing guidelines are set with wide safety margins. "People should eat fish," a trade group spokesman said. "They should just choose wisely."

The report lands amid a continuing fight over mercury regulation. The EPA this year issued the first rules limiting mercury from power plants, but critics sued, saying the cap-and-trade approach lets hot spots persist.

Health experts advise variety — smaller fish like salmon, shrimp, tilapia and canned light tuna run far lower in mercury — rather than avoidance.