Mislabeled fish a national problem

Tests show a third of samples from 21 states to be fraudulent

US consumers are frequently served a different type of fish than what they pay for, according to results released Thursday from one of the nation’s largest seafood fraud investigations.

Between 2010 and 2012, the nonprofit Oceana collected more than 1,200 seafood samples from 674 retail outlets in 21 states and conducted DNA testing that found one-third of the samples were mislabeled.

Fish advertised as grouper, cod, and snapper were often less desirable, cheaper, or more readily available species, according to Oceana, a Washington, D.C., group that focuses on fighting seafood fraud.

Grocery stores in the Boston region claiming to sell cod substituted another fish 31 percent of the time, the report said.

DNA testing found that 52 percent of the samples were misrepresented in Southern California, the highest mislabeling rate nationwide.

Of 120 samples from across the country that were advertised as red snapper, only seven turned out to be that fish.

“Everywhere we looked for seafood fraud, we found it,” said Beth Lowell, a campaign director for Oceana. “It’s not a regional issue. It’s a widespread problem across the US that needs national attention.”

The results are in line with The Boston Globe’s 2011 “Fishy Business” investigation. The newspaper found that nearly half of the fish tested at 134 Massachusetts restaurants and supermarkets was mislabeled.

In many cases, less desirable and cheaper species took the place of fresh, local varieties. A follow-up report published last fall revealed most of these restaurants were still substituting seafood.

“Fish fraud is a nationwide problem, cheating consumers and fishermen from Massachusetts to California,” said US Representative Edward Markey, a Malden Democrat.

“That’s why we need a national solution that increases­ inspections, gives consumers simple labeling information, and punishes bad international actors. I will soon be introducing a bill that would do all of these things, bringing trust back to the table in seafood restaurants and stores across the country.”

Last summer, Markey and now-retired US Representative Barney Frank filed legislation that would force the industry to publicly track fish from the time it is caught and impose hefty fines for violations.

Markey said that he plans to file the bill in the House of Representatives in coming weeks. Senator Mark Begich, an Alaska Democrat, is working on a similar proposal.

Massachusetts lawmakers have taken steps to combat seafood fraud with a bill introduced in January that would levy fines on supermarkets and restaurants that mislabel seafood.

It also calls for a ban on the sale of escolar, an oily species known as the “ex-lax” fish because of the gastrointestinal problems it can cause. Escolar is often misrepresented as white tuna at sushi restaurants.

Businesses caught substituting fish for varieties like Atlantic cod, Atlantic halibut, red snapper, and grey sole could, if the bill is signed into law, face fines of up to $800 and have their licenses­ to operate suspended or revoked after repeat offenses.

The measure has been referred to the Legislature’s Joint Committee on Public Health.