Revealed: seafood fraud happening on a vast global scale

Guardian analysis of 44 studies finds nearly 40% of 9,000 products from restaurants, markets and fishmongers were mislabelled

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A Guardian Seascape analysis of 44 recent studies of more than 9,000 seafood samples from restaurants, fishmongers and supermarkets in more than 30 countries found that 36% were mislabelled, exposing seafood fraud on a vast global scale.

Many of the studies used relatively new DNA analysis techniques. In one comparison of sales of fish labelled snapper" by fishmongers, supermarkets and restaurants in Canada, the US, the UK, Singapore, Australia and New Zealand, researchers found mislabelling in about 40% of fish tested. The UK and Canada had the highest rates of mislabelling in that study, at 55%, followed by the US at 38%.