DNA Testing Proves Restaurants Often Lie About What Kind of Fish They're Serving

Guzzle & Nosh

Sea bass at a fish market.

Maybe the latest crime show spinoff ought to be CSI: Seafood. More than one-fifth of the nearly 200 pieces of seafood bought at retail stores and restaurants in New York, New Jersey and Connecticut weren't what they claimed to be, according to an investigation in the December issue of Consumer Reports.

To verify the identities, an outside lab used DNA testing method similar to the genetic fingerprinting that criminal investigators use. The results revealed that the fresh and frozen samples were sometimes mislabeled as a different fish species, incompletely labeled or misidentified by employees.

Xesc Arbona

Seafood sometimes isn't what it seems -- even if the label says so.

"Whether deliberate or not, substitution hurts consumers three ways: in their wallet, when expensive seafood is switched for less desirable, cheaper fish; in their health, when they mistakenly eat species that are high in mercury or other contaminants; and in their conscience, if they find out they've mistakenly bought species whose numbers are low," said Kim Kleman, editor-in-chief of the magazine.

Highlights from the findings:

• Only four of the 14 types of fish bought -- Chilean sea bass, coho salmon, and bluefin and ahi tuna -- were always identified correctly.
• 18% of the samples didn't match the names on placards, labels or menus. Fish were incorrectly passed off as catfish, grey sole, grouper, halibut, king salmon, lemon sole, red snapper, sockeye salmon and yellowfin tuna.
• Four percent were incompletely labeled or misidentified by employees.
• All 10 of the "lemon soles" and 12 of the 22 "red snappers" weren't the claimed species.
• One sample, labeled as grouper, was actually tilefish, which averages three times as much mercury as grouper. The U.S. Food and Drug Administration (FDA) advises women of childbearing age and children to avoid tilefish entirely.

For more information on labeling, shoppers can visit www.GreenerChoices.org.