One of every five pieces of seafood bought from a Calgary restaurant or grocer was mislabelled at best or an entirely different species than what was claimed on the packaging, a new study published Monday finds.
The latest study in what’s been a long-identified trend across Canada has major implications for consumers’ health and wallets, as well as for the protection of endangered species, one of the study’s authors tells Global News.
“There’s no way for you as the consumer to have any idea if what you bought is what you got when you’re buying sushi. And that’s just the sad reality of it right now,” says Matthew Morris, associate professor of biology at Ambrose University in Calgary.
The problem is wider than your favourite all-you-can-eat sushi joint, according to the study published Monday in PeerJ’s biodiversity and conservation journal.
Students from Ambrose, which describes itself as a private Christian liberal arts university, worked with peers at Mount Royal University and the University of Calgary between 2014 and 2020 to sample a variety of seafood at grocers and restaurants in the city and cross reference their “DNA barcode” with what was on the label.
The results found that roughly one in five products were mislabelled to the point where the wrong species was substituted for what was sold. That includes both invertebrates such as shrimp, oysters and octopus as well as finfish like cod or salmon.
Misidentification rates were slightly higher, around one in three, when “semantic mislabelling” was included — a broader classification where an inaccurate label was used on something like “freshwater eel,” but consumers were likely still getting some form of eel.
But Morris explains that the most egregious instances are when a student purchased a cut of Atlantic salmon, only to find they had received rainbow trout that was manipulated to give its flesh the same pink colour as salmon.
“In a case like that, you’ve been genuinely hoodwinked,” he says.
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For some species of fish, Morris says the mislabelling is far more widespread. In “virtually every” example of red snapper samples sold, the actual product is typically tilapia, he says. That’s because red snapper is getting more rare in the wild while tilapia is cheaper and more easily farmed.
Getting a cheaper fillet than what you paid for is the tip of the iceberg, Morris warns. If someone is eating a piece of seafood they’re not expecting to be high in mercury, it can have major implications for someone who might be pregnant and is supposed to avoid it in their diet, he says.
In one particularly worrisome case researchers came across, a species of tuna sold at a sushi restaurant was in fact escolar, a fish that produces a form of fatty acid linked to gastrointestinal distress that has landed it the dubious distinction as the “laxative of the sea.”
“Some people have landed in the hospital because they’ve eaten too much of this particular product,” Morris says. “So at an all-you-can-eat-sushi bar, that’s not the thing that you want to be encountering.”
The other concerns are largely conservational in nature, particularly if a cut is sold as a thriving member of the marine ecosystem but is in fact a protected species.
How can you spot a mislabelled fish?
Morris says landlocked Calgary was one of the few major markets not yet studied for mislabelling, but he suspects the team’s estimates are “conservative.” Previous studies have shown even higher rates of misidentification, he notes.
A 2017 study from advocacy group Oceana Canada found that nearly half (46 per cent) of the seafood sampled from Ottawa vendors was mislabelled; a follow-up study the next year covering five Canadian cities found similar rates (44 per cent) of misidentification. A 2021 Oceana Canada study looking at Montreal found labels were wrong 60 per cent of the time.
But it’s not just a Canadian problem, with similar rates of misidentification seen in the United States and globally. Researchers in Hawaii had similar findings to Calgary’s, with one in five products in a 2020 study found to be mislabelled.
Morris says the United Nations has led initiatives to improve regulations around traceability in recent years, implementing a tracking system that can see some consumers scan a QR code on their packaging to see where a particular fish was caught and learn more information that way.
The Calgary researchers don’t have data during the depths of the pandemic and its aftermath, so they say more study is needed to see if labelling practices have improved in recent years.
Canadian rules do cite traceability in their requirements, but Morris feels that asking suppliers to keep better records does not go as far as electronically tagging and tracking the path of fish from the water to the table.
“For the general consumer, when you go to the grocery store to buy a seafood product, you have no way of knowing if that product is what you think it is,” Morris says.
That said, there are a few tips Morris has to identify whether “what you bought is what you got.”
For one, he recommends buying “head-on” fish — seeing the full package, in other words, can help to reduce instances of buying the wrong seafood.
Checking the package for certification by the Marine Stewardship Council (MSC) means the product was harvested sustainability and is also “far less likely to be mislabelled,” Morris says.
At a restaurant, Morris says it’s hard to see what package a fish comes out of before it’s cooked and plated, even with some sushi or hibachi restaurants where meals are prepared in direct line of sight.
But as a general rule, he also recommends not buying fish with very generalized labels like “tuna,” “salmon,” or “fish and chips.” A specific label like Atlantic or sockeye salmon is more likely to adhere to the species, he says.
“You would never go to the grocery store and buy a bird salad or a mammal sandwich. So don’t purchase something with a vague label,” he says.
— with files from Global News’ Anne Gaviola
