Next time you buy fish at the supermarket, it may not be what it appears to be - according to the authors of a new paper on truth in food labelling in the European seafood industry.

Mother Jones reports that researchers from the School of Biology and Environmental Science at UCD found a surprising 25 per cent of haddock and cod products "randomly sampled from supermarkets, fishmongers' shops and take-away restaurants" in Dublin "were genetically identified as entirely different species from that indicated on the product labels".

The team also stated that 28 out of 34 selected samples of smoked fish were found to be labelled incorrectly.

"These results indicate that the strict EU policies currently in place to regulate seafood labelling have not been adequately iimplemented and enforced," they said.

The paper - Smoke, mirrors, and mislabeled cod: poor transparency in the European seafood industry, by Dana D Miller and Stefano Mariani - is published in the current issue of the journal Frontiers in Ecology and the Environment.