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Fish DNA Survey

Students discover mislabelling in Fish DNA Survey

Grade 12 biology students recently participated in the Let’s Talk Science Fish Market Survey Project, supported by the Centre for Biodiversity Genomics at the University of Guelph and other community partners. Through this data collection project, students had the opportunity to contribute real data to a project about food fraud.

“It was a good experience for the class as it gave us a chance to apply our knowledge to an area outside of the classroom. We now have a stronger understanding of how formal studies are carried out. It was interesting to see the results come in after we tested all the samples.” Leah

As part of the project, students across Canada were asked to collect samples of fish from local grocery stores. The fishes of interest included cod, swordfish, Sockeye and King salmon, snapper and Red snapper, as well as Alaskan and Pacific halibut. Students uploaded data about their specimens, including the purchase location, the price, the species indicated on the label and photos of the samples.

Small pieces of tissue from the fish were removed, placed into vials and shipped to the University of Guelph, where the fish DNA was extracted, amplified using Polymerase Chain Reaction (or PCR) and DNA barcoded.

The barcodes go into BOLD Data System, a publicly accessible database of DNA barcodes accessible by researchers worldwide.

The Results

Once the results were in, the students learned that of the Canada-wide 223 sequenced fish samples, 38 of the samples were labelled as species that aren’t supposed to be consumed in Canada according to the Canadian Food Inspection Agency Fish List. Five fish samples were found to be incorrectly labelled, and were being sold under the wrong name. The overall Canada-wide results indicated that approximately 19% of the fish samples collected had labelling errors of some kind.

HDCH sent in ten samples collected from local grocery stores including Fortinos, Zehrs, Longos, Sobeys located in Ancaster, Hamilton, Brantford and Waterdown. All of these samples proved to be appropriately labelled.

“This project was an excellent opportunity for us. It proved how high the possibility of fish mislabelling and the potential for exploitation is. It was enlightening, and at the same time disturbing, to see how the market is run.” Theoktisti

This Matters

There are many consequences to product mislabelling. Consumers could be exposed to toxins and allergens. Consumers may also be paying more than their fish is worth. Fish populations can be impacted, including species at risk, as it would not be clear to consumers if the fish was harvested in a sustainable manner.

“Participating in the fish DNA barcoding was a great way for us to see how what we were learning in our class is used in research. Seeing the results also opened our eyes to the fact that the fish we are buying may not be what the label says that it is and that we are able to help find the problem in the industry as high school students simply by sending in a small piece of fish.” ~ Owen