When you buy fish, are you really getting what you pay for? A new study shows a lot of seafood is being widely mislabeled.

It’s happening in grocery stores and restaurants, and it means you don't always get the seafood you think you're buying.

Wrapped in plastic or swimming in sauce, buying seafood can sometimes be a bait and switch experience says Oceana, the international ocean conservation group.

“Consumers are getting ripped off. They are often getting less desirable, cheaper fish,” said Beth Lowell, Oceana campaign director.

Oceana says DNA testing revealed 39 percent of 142 samples purchased this summer in New York City were mislabeled — replaced with seafood of lower quality and value.

It found the highest rate of fraud at sushi bars. All 16 sushi bars surveyed had mislabeled fish 94 percent of white tuna turned out to be Escolar — a fish noted for its laxative-like effects.

Red snapper, a delicacy from the Gulf of Mexico, is popular on restaurant menus and in grocery stores, but 79 percent of the red snapper Oceana bought was something else; everything from different types of snapper to a potentially dangerous fish.

“We found tilefish which is actually on the FDA do not eat list because of its high mercury levels,” said Lowell.

Which is a recommendation for pregnant women, nursing mothers and young children. The results did not surprise New York seafood wholesaler Vinny Dimino

“It's not just the city, it's worldwide,” he said.

In fact, previous Oceana studies found alarming rates of mislabeling in Miami, 31 percent, Boston, 48 percent, and Los Angeles, 55 percent.

The Food and Drug Administration regulates seafood labeling. Wholesaler Dimino says he knows what he's buying, but for consumers he says it's a matter of trust.

“If they hired 1,000 inspectors a day they still couldn't stop it. They are trying but they can't. Like I said, you have to rely on the people you buy from,” he said.

To crackdown on seafood fraud, the National Fisheries Institute, an industry trade group, set up the Better Seafood Board. Its members promise to label seafood according to state and federal laws.

“Because the companies that do things right feels a disadvantage when either their competitors or their customers mislabel a product for financial gain. It's just wrong,” said John Connelly, National Fisheries Institute.

To protect yourself, ask questions of your server or the person at the fish counter. If they don't know where the fish is from or hem and haw, move on to another choice. Another clue: if the item seems to be a real bargain, it may well be something else.

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