Assessment of heavy- and semi-metals contamination in edible seaweed and dried fish sold in ethnic food stores on the Italian market

Abstract

In this study, heavy- and semi-metals (As, Cd, Cr, Hg, Pb, Tl) content in seaweed and dried fish purchased in ethnic food stores located in southern Italy was assessed. In algae, also iodine was quantified. As was the most abundant element in seaweed (average = 8.19 ± 6.62 mg/kg), followed by Cd (0.38 ± 0.25 mg/kg), and Pb (0.12 ± 0.10 mg/kg). In fish, As was the most abundant element (average = 0.47 ± 0.37 mg/kg), followed by Hg (0.12 ± 0.17 mg/kg). The 19.2% (5/26) of seaweed samples exceed the limit for Cd suggested by CEVA (France), while 12.5% (1/8) of fish samples exceed the limit for Pb imposed by Regulation (EC) No. 1881/2006. Correlations among Hg-As, Cr-Tl, Pb-Tl (seaweed), and As-Cd, As-Pb, Cd-Pb, As-Cr (fish) were observed. The chemometric analysis resulted in a satisfactory clusterization of samples for product type, while the grouping for geographic origin was less precise. Heavy- and semi-metals content in fish and seaweed, as well as iodine levels in algae commercialized in southern Italy, do not seem to be of concern for consumers, but constant monitoring is desirable to increase the data on contamination of these products and for the risk assessment process.