Toxic metals (Hg, Pb, and Cd) in commercially important demersal fish from Mediterranean sea: contamination levels and dietary exposure assessment

Abstract

Mercury (Hg), cadmium (Cd), and lead (Pb) were quantified in muscle tissue of 5 species of demersal fish (european conger eel, rosefish, brown ray, blackbellied angler, and red mullet) commonly consumed in Italy. In all species studied, Hg was the most abundant element, followed by Pb and Cd, which exhibited comparable levels. Cd and Pb concentrations did not differ either within individuals of the same species or among various species examined, whereas Hg accumulation was species-specific. Significant positive correlations between Hg concentrations and fish length for the 5 characterized species were observed. From a public health standpoint, Pb concentrations were under the legal limit for human consumption indicated by European Regulation, whereas Hg and Cd content occurred at levels exceeding the respective critical values in most of the samples examined. The estimated weekly intakes (EWIs) as well as the target hazard quotients (THQs) for Cd and Pb indicated that fish were safe for human consumption, whereas major concern was related to Hg. Fish size-related changes in Hg concentrations determined high THQ and EWI values relatively to larger size fish consumption of these species, except for red mullet, suggesting potential health human risk. A continuous surveillance system of Hg content in fishery products, especially in certain species that for physiological reasons concentrate Hg more easily than others is crucial for consumer health protection.

Practical application: The present article deals with metal (Hg, Cd, and Pb) concentrations in commercially important demersal fish from Mediterranean Sea. The dietary intakes of these elements have been estimated and the dietary exposure assessment was calculated. This kind of study will help the consumers to make an informative choice when buying fish.