Fresh report warns fish fraud extends to one fifth of global catch

Menu of misinformation
Some studies suggest that up to 30 per cent of seafood products may be mislabelled in restaurants, with the report citing cases from around the world, from ceviche stands in Latin America and seafood eateries in China to canned tuna products in the European Union.
While as much as one third of aquatic products sold in the United States may not conform to package descriptions, less than one per cent of imports are tested, the report warned.
What drives fish fraud?
Economic incentives are the most widespread driver of fish fraud.
Selling Atlantic salmon, almost all of which is farmed, as Pacific salmon, most of which is wild caught, delivers a nearly $10 benefit per kilogramme.
Some fraud occurs to mask the geographic provenance of a product or to suppress evidence of above-quota landings, which may pose risks to the sustainability of fishery stocks.
Finding fraud
Fish fraud is defined in the report as “a deliberate practice intended to deceive others” and can pose risks to biodiversity, human health or economic systems, according to Food fraud in the fisheries and aquaculture sector, produced by FAO through cooperation between its Fisheries and Aquaculture Division and the Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture.
The main categories of fish fraud are:
- adding water to unprocessed fishery products to bolster weight and price
- adulteration (adding colouring to make tuna look fresher)
- counterfeiting (imitation shrimp made from starch-based compounds)
- simulation (packaging surimi to seem like crab meat)
- diversion (distributing legitimate products outside of their intended markets)
- misbranding (such as incorrect claims about sustainability)
- overrun (involving overfishing)
- species substitution (selling tilapia as red snapper)
- tampering and mislabelling (involving origins and even expiry dates)
- plain theft
Meanwhile, the human welfare risks of some seafood fraud are evident as some fish pose risks when eaten raw, while re-freezing seafood increases the risk of bacterial growth.
Catching fishy business
The global scale of fish consumption – targeting over 12,000 seafood species – the diversity of fraud type and the lack of standardised regulatory or legal definitions, make global estimates difficult to assess, but there are novel ways to tackle the scourge.
Advanced laboratory tests can be effective in identifying substances, but access to these methods is limited.
Meanwhile, the report shows that portable X-ray fluorescence and machine-learning models are innovations that could help cut fraud and make regulations more enforceable.
To quash fish fraud, the new report advocates for:
- harmonised labelling requirements
- mandatory inclusion of scientific names where possible
- better traceability systems
Adding science to the tacklebox
Given its complexity, identifying the crime is not straightforward, but the report goes into considerable detail about how advances in science can contribute to tackling fraud, including:
- A standard method to determine whether and how many times a seafood product has been frozen has so far proven elusive, but differences in the fatty-acid composition of wild and farmed fish may be used to detect fraud
- Carbon and nitrogen ratios to determine the geographical origin of major commercial fish species
Netting offenders
Prevention and enforcement are critical to reduce and eventually eliminate fish and all food fraud, according to the report, which reviewed concerted efforts to tackle cases in Argentina, Italy and the United States.
An investigation using DNA-barcoding to assess the scale of mislabelling in Los Angeles, California, found that while it is quite low in processing plants, it is moderate among grocers and particularly prevalent in sushi restaurants.
A local initiative by local academia, industry, government stakeholders – together with an education campaign coupled with ongoing blind tests, reduced seafood mislabelling in the focus area by two thirds over 10 years.
What the UN’s doing
Part of UN ongoing efforts include:
- FAO and the Codex Alimentarius Commission – the international food standards body – are working on toughening international standards to combat food fraud
- through the Joint FAO/IAEA Centre, FAO offers technical support to members that need to bolster their testing capacities.
Find out more about what FAO is doing here.
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