Contaminant metal concentrations in holothurians: Seasonal, sex and tissue variations

The main goal of this study was to investigate seasonal contaminant changes in three sea cucumber species caught in the North Atlantic. The risk associated with the consumption of these target species, taking into account the consumers age group, was also evaluated. For this purpose, the concentration of toxic metals cadmium (Cd), lead (Pb) and mercury (Hg) was analyzed during spring, summer, autumn and winter in two different tissues of female and male holothurians. Average concentration of the Cd, Pb and Hg were different among the studied species, and significant differences were observed considering sex, tissue and seasonality factors. The average values (dry weight) of the Cd and Hg of Holothuria arguinensis (Cd: 0.10 mg kg^-1; Hg: 0.10 mg kg^-1), Holothuria forskali (Cd: 0.10 mg kg^-1; Hg: 0.07 mg kg^-1) and Holothuria mammata (Cd: 0.19 mg kg^-1; Hg: 0.17 mg kg^-1) were lower than those regulated by the European Union. On the other hand, the average Pb values (dry weight) were high in Holothuria arguinensis (Pb: 2.97 mg kg-1) and Holothuria mammata (Pb: 1.77 mg kg-1). The risk associated with the consumption rate (CR_lim) of these species is low for Cd and Hg and high for Pb for adults and children, based on the maximum concentrations rate (CR_lim) of each metal. Results such as presented in this work are scarce or non-existent, potentially contributing to a database that allows for the future development of new regulations that limit the maximum concentrations of metals in the consumption of echinoderms.