20% of the fish you eat is likely mislabelled, study finds

The next time you order a dish with white tuna from your favourite restaurant or buy the fish from a grocery store, be careful: it might, after all, not be white tuna. Instead, it could be escolar, a fish that can cause diarrhea within 30 minutes.

That’s one of the results of a six-year study that found one in five seafood products in Calgary are mislabelled, misleading the consumer about the kind of fish they’re eating.

The study, conducted by Ambrose University — which describes itself as a private Christian liberal arts university — in partnership with the University of Calgary and Mount Royal University, sampled more than 400 seafood products between 2014 and 2020.

Matthew Morris, a biology professor at Ambrose University and the study’s lead researcher, sent many of his graduate and undergraduate students to different grocery stores, where the students asked for a tissue of the fish. Sometimes, the professor would offer them cash for lunch at a sushi restaurant to collect samples.

The students photographed the receipt or label in the store and brought the samples to a laboratory. The DNA was sequenced, and the information was later run in a program that recognized the species of fish. The researchers learned a third of the labels didn’t match the species’s name.

How fish are being mislabelled

They found three kinds of mislabelling: first was when the labels didn’t correspond to the actual name of the fish, but the consumer knew what they were buying; the second was when the product was different from what the consumer thought they were getting; and in the third, the market name of the fish didn’t fall under any permissible label maintained by the Canadian Food Inspection Agency (called the “Fish List”) and was so unusual that the researchers couldn’t trace its identity.

When the first kind of mislabelling was eliminated, the problem had dropped to one in five seafood products. The most egregious example was when the researchers found a product labelled as a crab was actually a fish species. Once, a product labelled saltwater eel, which wasn’t even permissible under the Fish List, turned out to be a snake eel.

“You find it down 200 meters deep in the ocean,” Morris said. “What on earth was it doing in a Calgary market?”

Previous studies have shown the issue is especially worse in coastal cities, and in some cases, products there are mislabelled 40 to 50 per cent of the time, research by ocean conversation group Oceana Canada has found. However, although the problem is not as severe in Calgary, its landlocked feature has not prevented the mislabelling of fish.

How consumers are affected

Morris said the issue affects consumers in three ways: First, they are being ripped off by being charged for something more expensive; then, there are health concerns, as seen with the mislabelling of escolar; lastly, consumers might unknowingly consume endangered species.

The most common example of mislabelling was tilapia being sold as red snapper.

“When you see the market is just teeming with red snapper, it makes you think, ‘Oh, red snapper is doing fine,'” Morris said.

“But when most of the red snapper is tilapia, it leads to this false sense of security for red snapper, and then makes it less likely to incentivize conservation.”

He said some of the mislabelling are genuine human errors. The rest are deliberate acts of fraud.

What consumers can do to avoid being misled

The problem isn’t Canadian but international, said Morris. He also said initiatives by the United Nations, such as applying a tracking system that allows consumers to see where the fish was caught and packaged through a QR code, have improved the fish’s traceability. However, since the project doesn’t include any data beyond 2020, Morris and his researchers cannot say how the issue has evolved.

However, more research is needed.

“It’s just so hard to know where the fraud is occurring,” he said. “Is it occurring at the boat? Is it occurring in another country, in processing plants, before it ever gets to Canada? So before you can really nip it in the bud, you have to understand where in the supply chain this is happening.”

The best way for consumers to prevent buying something other than what its label claims the product to be is to buy the fish with its head on.

“If you can see the whole creature right, you’re less likely to be misled,” Morris said.

Consumers can also purchase products that are certified by the Marine Stewardship Council (MSC), which means the product was harvested sustainability — as researchers have found they are less likely to be mislabeled.

Morris also suggests buyers look for specific labels, such as sockeye or Atlantic salmon, instead of “tuna”, “salmon,” or “fish and chips.”