Heavy metal content and molecular species identifcation in canned tuna: Insights into human food safety

Abstract

Canned tuna in olive oil and in brine of the most popular brands sold in Italian markets were analyzed to verify the authentication of transformed products, with the aim to unveil commercial frauds due to the substitutions of high value species with species of low commercial value, and to assess the health risk of consumers related to cadmium (Cd), lead (Pb) and mercury (Hg) contents. Species authentication was evaluated with amplifcation of COI DNA barcode and confrmed the declared species. Among tested metals, Hg had the highest concentrations, followed by Cd and Pb. None of the tested samples surpassed the European regulatory limits no. 1881/2006 fxed for Hg and Pb, whereas one batch of canned tuna in olive oil exceeded standard for Cd. Risk for human health was evaluated by the metals daily intake and target hazard quotient (THQ). As a result, Cd and Pb did not exceed the toxicological reference values established by World Health Organization (WHO) and the Environmental Protection Agency (EPA). Conversely, Hg content suggests a consumption no more than once a week and a continuous surveillance of this fshery products for consumer protection.