Authentication of sushi and sashimi products from northeastern Pará, coastal Amazon, by DNA barcoding reveals commercial frauds and potential threats to human health and environment

Abstract

The Japanese cuisine has become a huge success in Brazil over the last years, but little is known about the fisheries resources commercialized to supply this specific market. In the present study, we carried out the first molecular characterization of sushi and sashimi products available in northeastern Pará, coastal Amazon, in order to infer what species have been actually exploited in this trade. We sequenced two mitochondrial DNA regions from 172 samples (138 of fish and 34 of shrimp-derived products) that were divided into 28 haplotypes. The comparative analyses with public DNA barcode databases revealed eight species of fish and three of shrimps among the samples, including cases of commercial frauds. For instance, Ruvettus pretiosus and Lepidocybium flavobrunneum were traded as “anchova” (bluefish), a valid and specific commercial name of Pomatomus saltatrix. Both species can cause gastrointestinal issues, which has led to restrictions on their sale in several countries. All commercialized shrimp-derived products were labeled as “camarão” (shrimp), as generic trade name that could not be applied to identify each species. Furthermore, potentially threatened species have also been recorded in the commercial products, such as Salmo salar and Cynoscion acoupa, classified as “nearly threatened” and “vulnerable”, respectively. The later, popularly known as “pescada-amarela” (acoupa weakfish) has been commercialized as “peixe-branco” (white fish), a designation that is not recognized by the Brazilian regulatory agencies. Both DNA markers (COI and 16S rRNA) were highly efficient in identifying the species from all samples, providing the first list of exploited species for Japanese cuisine along the coastal Amazon. Besides revealing issues in the commercialization of Japanese food items, we recorded a largely overlooked diversity of traded species. These data represent a potential risk to public health and to the environmental conservation such as the presence of exotic species and the exploitation of threatened species that should be considered to support effective policies for the regional regulation of this market.