Health risk assessment for the consumption of fresh and preserved fish (Alosa agone) from Lago di Como (Northern Italy)

Background Although banned in many countries for decades, DDTs and PCBs still represent a global threat to food safety. As these contaminants are still present in aquatic ecosystems, fish can be an important contributor to their total dietary intake. Objectives Alosa agone specimens were sampled over a period of 10 years (from 2006 to 2015) to provide a representative overview of the DDT and PCB levels of Lago di Como, a deep Italian lake where a DDT input due to secondary sources was observed in recent years. The potential health risk from the consumption of both fresh and preserved fish was evaluated. Results While DDT levels have generally decreased during the monitored period, reaching quite stable levels, PCB concentrations were variable, with values exceeding, in some cases, the European Union limit for human consumption and enabling potential carcinogenic effects. However, typical local processing of this fish species markedly appeared to decrease these contaminant levels, thus making the fish product (called missoltino) a safer food. Conclusions The results of this work highlighted the need of continuous biomonitoring of those contaminants considered a past issue along with the emergent ones.