Early this year, the discovery that horsemeat was being substituted for beef in some European foods triggered widespread concern over food fraud in the EU. This substitution, deemed the “horsemeat scandal,” was eventually determined to be affecting around 5 percent of European beef products. But in the U.S., consumers have a different type of fraud to worry about. It is estimated that about one-third of seafood sold by retailers and restaurants in the United States is mislabeled, a problem that can have serious implications for public health.
What’s being done to combat this problem? Is an improved seafood traceback system on the horizon? Today, Food Safety News dives into the world of seafood traceability, looking at what can be done – and what’s being done – to trace fish and shellfish from water to plate.
According to the National Oceanic and Atmospheric Administration, 91 percent of the seafood consumed in the U.S. in 2011 was imported.
With over 1,500 species of fish and shellfish coming into the U.S. from all over the world and often going through several processing stages, verifying where seafood came from by the time it reaches the consumer can be difficult.
Another problem posed by such a complex industry is species substitution, which can be both inadvertent and intentional.
A 2012 study from ocean advocacy group Oceana found that, out of 1,200 seafood samples taken from 673 retail locations across the U.S., 33 percent were a different species from the one indicated to the consumer.
The most commonly mislabeled fish were snapper, which turned out to be another species 89 percent of the time, and tuna, of which 59 percent of samples collected were actually another fish. Of the “white tuna” the group tested, 84 percent was actually escolar, a fish that is banned in many countries as it can carry toxins that cause gastrointestinal illness when eaten in quantities over a few ounces.
Other in-demand fish for whom different species were commonly substituted included cod, grouper, halibut and Chilean seabass.
LeeAnn Applewhite, CEO of Applied Food Technologies, which performs DNA testing on seafood, says the species her company finds are mislabeled largely match those Oceana found were mislabeled.
“There’s a lot of mislabeling with sushi and sashimi tuna, and then it’s grouper, cod, halibut, salmon, all the higher value species,” said Applewhite in an interview with Food Safety News. “And it’s region-specific.”
In other words, different types of fraud are more common to different regions. While grouper and shrimp fraud are more prevalent in Florida, salmon fraud is seen more on the West Coast, where there are more species of salmon to mix up.
But, Applewhite pointed out, seafood fraud isn’t always intentional. In fact many times it’s a mistake.
“It’s extremely complicated because fishermen go out, and grouper don’t swim in one place all by themselves and cod in another place all by themselves,” she explained. “You have all these species swimming together and they catch thousands of fish on some of the big boats. They look alike, they’re in the same place, and once they’re filleted, nobody can tell the difference.”
And once seafood leaves the harbor, it can be even harder to keep track of, explained Dr. Lucina Lampila, Associate Professor and Extension Seafood Specialist in the Department of Food Science at Louisiana State University.
“When you’re a very large plant and you start to have lots get commingled, it’s a little dicier,” Lampila told Food Safety News. “There’s still a record of what boat it came from but it can get a little more confusing.”
Why it’s dangerous
What’s the harm in eating one type of fish instead of another, other than paying for something you didn’t get?
For starters, the mislabeling of escolar as tuna creates a health risk, as the former fish is a waxy, oily species that can cause severe gastrointestinal illness, unlike tuna.
Another health problem is created when fish containing histidine are mislabeled. Histidine can be converted to histamine over time by enzymes released in the fish. High levels of histamine, an allergen, can cause illness when ingested by humans. In order to prevent the decay that leads to histamine production, histidine fish must be kept at low temperatures. If a histidine-carrying fish, such as tuna or swordfish, is labeled as a fish that doesn’t carry histidines, such as tilapia or grouper, that fish may not be handled in a way that prevents histamine from forming.
While it’s less likely that a histamine-producing fish, which usually have dark flesh, will be confused for one that does not produce histamines, Oceana did find some of these substitutions, such as catfish for grouper.
“Hazards such as allergenic proteins and scombrotoxin formation are associated with some species but not others, presenting potential food safety risks if the food is not accurately labeled,” notes the U.S. Food and Drug Administration, the agency in charge of regulating seafood sold in interstate commerce.
Another hazard that arises from mislabeling seafood is the possibility of unknowingly serving fish from a region that’s been flagged for a health risk.
“If an area of the water is closed because of Ciguatera and snapper is caught in that area and then labeled as a species not typically from that area, that’s a health issue,” said Applewhite.
Ciguatera is a toxin found in some tropical reef fish. Another area-specific risk is Vibrio bacteria, found in shellfish when water temperatures get too warm.
“If the fish is being mislabeled and you’re trying to contain an outbreak, you’d want to know where the fish was harvested and what date and if anyone else had eaten it so the doctors know what kinds of symptoms to look for,” said Kim Warner, Senior Scientist at Oceana and author of the seafood fraud study. “These health concerns are reasons why you’d want a traceability system in place so you can quickly identify the source of the fish.”
Some fish, such as tilefish, contain high levels of mercury, and women who are pregnant or breastfeeding are advised to avoid these fish. Substitutions of these species for others can also pose a health risk.
Using DNA testing to combat seafood fraud
Back in 2000 when LeeAnn Applewhite started Applied Food Technologies (AFT), DNA testing for seafood was virtually nonexistent. The predominant testing method at the time was protein analysis, which requires subjective interpretation of results and is ineffective for cooked foods.
“I hated those methods and I knew everything was going molecular,” recalled Applewhite. “So I started writing federal grants to address this.”
By 2004 the company had developed the first seafood DNA testing methods to be accepted by FDA. Then in 2005, AFT was asked by two major commercial food suppliers – U.S. Foods and Sysco – to begin DNA testing on the fish they were purchasing.
“When we started this in 2005, we were seeing extremely high levels of substitution with catfish,” said Applewhite. “It was actually Vietnamese catfish, not U.S. catfish.”
The company also detected high levels of substitution for grouper, snapper and cod — In some cases, 60 percent of fish that was supposed to be one species would be mislabeled. But over the years, AFT has seen a “dramatic drop” in the amount of mislabeled seafood brought to its clients, according to Applewhite.
“It’s all down well below 20 percent now.”
Since it developed its first DNA tests, the company has expanded its database of DNA sequences to include over 1,500 seafood species from around the world. Before a new species is entered into the system, it is taxonomically validated by a museum of natural history. AFT also does backup testing for FDA, which performs DNA tests on all seafood subject to an import alert.
The government has also become concerned with seafood fraud over the past few years. Starting in 2007, after the substitution of toxic pufferfish for monkfish caused a series of illnesses in the U.S., FDA launched its own initiative to validate fish species via DNA testing.
Under the agency’s Barcode of Life initiative, it has developed authenticated sequencing for 172 fish species.
“Species substitution has been an area of concern for the FDA and within the seafood industry for some time,” said a representative for FDA’s Center for Food Safety and Applied Nutrition in an email to Food Safety News. “As a result of these concerns, the FDA has recently invested in significant technical improvements to enhance its ability to identify seafood species using state of the art DNA sequencing.”
The agency said it has been collecting samples to determine where DNA testing efforts could be most effective.
“In Fiscal Year (FY) 2012, the FDA conducted surveillance sampling for species substitution at wholesale distributors, gathering approximately 800 individual filets from approximately 100 different lots of fish to verify the accuracy of the labeling utilizing the new DNA testing capabilities,” said the agency. “Once we finish compiling the results, the FDA will have a better idea of where to conduct future sampling and enforcement efforts.”
But going forward, many predict that DNA testing will be industry-driven.
Craig Wilson, vice president of food safety at Costco, said the company has been DNA testing its incoming seafood for a couple years.
“We’re doing a lot of DNA species confirmation and that helps us quite a bit,” Wilson told Food Safety News. While he can’t speak for other companies, Wilson said, “I think more and more people are doing that.”
Keeping tabs on seafood
To move safe and properly identified seafood from the water to the table not only requires species validation, but also a system that retains information about the origin of a product as it travels through the food supply.
The 2009 federal Country of Origin Labeling (COOL) law, enforced by USDA’s Agricultural Marketing Service, dictates that seafood entering the U.S. must be accompanied by a label indicating what country it came from and whether it was farm-raised or wild-caught. However, the rule exempts “processed” seafood – seafood that’s been smoked, boiled, or changed in any way.
After seafood is imported, it often makes many more stops before reaching the consumer, making it difficult to track.
“A lot of the data is required in fish being imported but it’s not following it through the supply chain,” said Warner of Oceana.
“It can go through ten or fifteen different brokers, ten or fifteen cold storages, and they’re handed all differently, and who the heck knows what happens?” said Wilson. “That part for a lot of folks can be incredibly complicated.”
After seafood enters the U.S., the only hard and fast law governing its traceability is the Bioterrorism Act. Passed by Congress in 2002, the Act dictates that food processors and handlers must be able to “identify the immediate previous sources and the immediate subsequent recipients of food.” The Act exempts restaurants and farms (including fish farms) from these requirements.
While this means seafood handlers must have a record of where they got a shipment of seafood and where they sent it, it does not affect the labeling that accompanies the food.
“I know who I got it from and who I sold it to, but we’re calling it different things, so it takes a while to try to map it up into our system to really see where that product is from and where it went,” explained Angela Fernandez, vice president of grocery retail and consumer packaged goods at GS1 US.
GS 1 is the global nonprofit organization that started the barcode system now used for all food items at grocery stores around the world. The group now offers a standardized tracing system for the various food industry sectors, including seafood.
Fernandez says the level of information passed from one seafood company to another depends on what the purchaser is asking for, and varies greatly from business to business. But overall, she says, the industry seems to be seeking better traceback systems.
“This is really where the industry has come to GS 1 and said, ‘Will you help guide us?'”
Many in the industry have come to GS 1 to help assess their current traceability systems and see where any breakdowns might exist.
“Right now we’re in the middle of doing a proof of concept with some of the large seafood players in the U.S.,” said Fernandez. “They believe that they’re capturing a lot of this information today in a standardized way, so we are currently working with them to map out all of the different processes that are happening with each supply chain role and seeing the information they’re capturing and how they’re capturing it to identify gaps that they have.”
Where will the change come from?
According to the Food Safety Modernization Act, signed into law in 2011, FDA must improve the traceability of the U.S. food supply in two ways: 1. Run pilot programs to see where traceback information needs to be captured and 2. Implement mandatory record keeping for high risk foods. Whether certain seafoods will be on the list of risky products remains to be seen.
The agency is also taking into account the results of two pilot studies on traceback conducted by the Institute of Food Technologists (IFT) – one on tomatoes and one on a frozen Kung Pao-style dish.
But how much these results and FDA’s ensuing action will affect the seafood industry is unclear.
“We’ll see how far it goes. Certainly IFT recommended that there be traceability and how it could be done, but it’s just kind of a wait and see,” said Lampila.
The agency has also indicated its intention to tighten its controls on seafood fraud through increased DNA monitoring.
Another option for regulation might come from Congress, where U.S. Representatives Edward Markey (D-MA) and Barney Frank (D-MA) have introduced the Safety and Fraud Enforcement for Seafood (SAFE Seafood) Act. The bill would mandate full traceability for all seafood sold in the U.S. by requiring data about the origin of a seafood product to follow it through every step of the supply chain.
However, experts agree that the industry is already moving towards a better traceback system, and that the effort will be a joint one between industry and government.
“There’s a traceability industry,” said Warner. “There are people trying out different models. I think the industry will find out what works and what’s the best way to handle this.”
One model that won’t work is FDA testing a majority of the seafood coming into the U.S., something for which the agency doesn’t have the capacity. Right now it is estimated that less than two percent of imported seafood is inspected.
“The FDA won’t be able to do it, but they can keep you from importing if you don’t have verification and can put some sort of system in place that assures that the verification is accurate,” said Wilson.
It’s a matter of a buyer being able to verify the supplier, according to Lampila.
“It takes setting up some rules and some oversight and actually FDA encouraging the processor: If you’re going to import, go visit the site and audit yourself or hire another auditor to go in.”
And if the vendor is able to verify the origin of his product, he will see a reward from consumers, she said. Some seafood vendors are now listing the exact location, down to latitude and longitude, where seafood was caught, sometimes even naming the boat.
“They are doing that and they are getting sales. They’re getting a premium for their product,” said Lampila.
“From my perspective, I see the industry wanting to do more than what we anticipate from the regulations, which I think is a good thing,” Fernandez weighed in.© Food Safety News