Fishy Business

Using DNA bar coding, ecological scientists in Ireland discovered that a significant percentage of fish sold in Dublin was mislabeled.

Dana Miller and Stefano Mariani, PhD, University College Dublin, found that 39 of 156 randomly sampled cod and haddock products (25%) were entirely different species. They found that 28 of 34 (82.4%) of smoked fish samples were mislabeled.

This problem extends beyond the European Union. Last year, Philip Hastings, PhD, and his colleague Ron Burton, PhD, of the University of California, San Diego, used DNA bar coding to determine that 25% of the fish served in New York restaurants was mislabeled.

Several issues arise from mislabeled fish. First, mislabeling leads to overpaying by consumers and others in the chain of production, according to Miller. (For more on this topic, see “Fish and Chips” on p. 16.)

The potential environmental repercussions are more serious. Mislabeling gives false impressions to consumers and fisheries agencies about resource abundance, said Dr. Hastings, a professor of marine biology.

“If a preferred species such as ‘scamp,’ a type of Caribbean grouper, is always in the markets, on menus, etc., we assume that it is common in the wild,” he told Food Quality. “In fact, the real scamp may be very rare, but substituting other species under that name gives a false impression that it is abundant. This has obvious implications for management agencies that are responsible for monitoring exploited populations, setting fishing quotas, fishing seasons, etc.”

Mislabeling also mars food traceability. “In theory, the requirement for seafood products to have correct and informative labels should restrict the access of products that have been obtained through illegal, unreported, and unregulated fishing activities into European markets,” Miller told Food Quality.

Food safety and quality are also affected. “Consumers could be allergic to a certain species of fish and unaware that they are eating this fish if the product was mislabeled,” Miller said. “Additionally, how can we be sure that other parts of the label are not changed in addition to the name, such as the ‘best before’ date?”

Random Testing One Answer

There are several ways to combat this problem. Routine DNA barcoding might help, Dr. Mariani said. “Even some random testing on a small percentage of fish products would ensure that everyone involved in the fish production chain acted more responsibly,” he told Food Quality. “It would be a little bit like doing some random doping tests on athletes. Ideally, this should discourage people” from cheating or acting carelessly.

Dr. Hastings agrees that random sampling may deter mislabeling. “It would not be feasible to do this for all or even most catches, but sporadic monitoring with penalties for consistent violators would be a deterrent and would reward the honest fishers.”

Consumer awareness can also be a weapon. “If consumers are made more aware of sustainability or mislabeling issues, they may ask questions about products more frequently when making purchasing decisions and pay more attention to label content and product appearance,” Miller said. “If retailers take notice of the changing demands of consumers, then perhaps they might make more of an effort to ensure that their products are of high quality with accurate labels and possibly even obtained from sources that use only responsible fishing practices.” ■