Traceability challenges and heavy metal risks in commercial shrimp and prawn

Mislabelling in the global fisheries sector raises concerns about the identity, safety, and sustainability of seafood products. It puts human health at risk when substitute species are contaminated with heavy metals that may cause chronic diseases and cancer. The aim of this work was to analyse mislabelling in shrimps and prawns sold in the Spanish market and possible risks of heavy metal ingestion. Analysis of labels, DNA barcoding for species identification and quantification of heavy metals were performed on 100 market samples, and health risk was calculated from standard indices. More than one half of individuals did not comply with European regulations about labels, principally for the absence of mandatory elements in the label. One third of the analysed shrimps were substitute species (not mentioned on the label), and a 10% did not comply with the legal European limits for heavy metals. The prawns Penaeus indicus and Penaeus latisulcatus from West Indian and Central/East Atlantic waters exhibited the highest heavy metals concentrations. Indices calculated for these two species, and for Pandalus borealis and Parapenaeus longirostris, suggest health risks if consumed daily. If those or other species from these polluted areas were employed as substitutes, mislabelling would encompass health risk.