Analysis requires only a gram-size sample of fish to produce an accurate reading. And with DNA bar coding, the fish can be raw, frozen, steamed or even deep-fried. (Deeds says sampling from canned fish is trickier because temperature and pressure breakdown the DNA, making it more difficult to get results.) Consumers will not be able to send their own samples to the FDA, but if they believe fraud has taken place, they can file a complaint with the agency, which may then conduct its own investigation.
In the meantime, private labs like ACGT, Inc., believe DNA testing of seafood is a business niche worth cultivating and are confident that seafood importers, wholesalers and retailers will embrace it, especially when the testing can come out to mere pennies per sample. "Even if the FDA ramps up its testing, with the amount of fraud going on, it can't monitor the entire industry," says Edward Diehl, director of business development for ACGT. "Is that something people are interested in paying? We'll find out. Increasingly, companies are starting to see that mislabeling affects their bottom line, and consumers are noticing that testing is being done. Pretty soon, they're going to demand it."
Since ACGT launched their seafood testing at the beginning of 2011, Diehl says his firm sees an average of 20 to 25 percent of the seafood samples fraudulently labeled to appear as a higher value fish. Although there is no official figure for how much seafood fraud takes place or costs, NFI spokesman Gavin Gibbons estimates it is in the tens of millions of dollars every year. An Oceana report found that at least 4.5 million kilograms of frozen catfish was sold as grouper or sole in the U.S. in just one year, netting $63 million, to take one example.
DNA bar coding is not foolproof, however. Although it can differentiate between Atlantic cod and Pacific cod, distinguishing a cod caught from George's Bank versus the Gulf of Maine is not easy unless the test is designed to look for a specific genetic marker. The same problem can happen when testing between the closely related northern bluefin and Pacific bluefin tuna, both of which face intense fishing pressure and population declines. And the ability to tell the difference between a fish that has been wild-caught or farm-raised gets complicated quickly, given that they share the same genetics, although there are other methods to distinguish them.
But testing methods are continually improving, and Deeds says portable sequencers for bar coding, which would allow inspectors to verify labeling of the species at the source, is not science fiction. With the necessary funding, Deeds says it could happen in the next few years. In the meantime, consumers should soon feel more confident about the identity of the catch of the day.