EFFECT OF FEEDING ON CADMIUM BIOACCUMULATION IN THE ECHINOID PARACENTROTUS-LIVIDUS (ECHINODERMATA)

Echinoids Paracentrotus lividus (Lamarck, 1816) were contaminated unde r laboratory conditions with Cd (as CdCl2) either from sea water or fr om both sea water and food (Posidonia oceanica leaves) simultaneously. The experimental results showed that Cd bioaccumulation in the digest ive tract wall and Aristotle's lantern of echinoids contaminated via b oth sea water and food was significantly less (as much as 50%) than wh en echinoids accumulated Cd from sea water only. The:opposite trend wa s observed for the coelomic fluid of these echinoids, These observatio ns suggest that food containing high Cd concentrations (1) reduces the efficiency of the digestive tract wall and Aristotle's lantern in tak ing up Cd from sea water, and (2) could enhance metal depurative activ ity of the echinoid coelom.