Allometry of heavy metal bioconcentration in the echinoid Paracentrotus lividus

Abstract

The relationships between concentration and size in Paracentrotus lividus were studied for seven metals (Zn, Pb, Cd, Fe, Cr, Cu, and Ti). In the calcified body compartment, Zn concentrations showed inverse power relationships, while concentrations of Pb, Cd, and Cr increased as power functions of echinoid size; Fe, Cu, and Ti concentrations did not vary significantly with echinoid size. In the non-calcified body compartment of the echinoid, the concentrations of Zn, Pb, Fe, Cu, and Ti showed inverse power relationships, Cd concentrations increased linearly, and Cr concentrations did not show any significant relationship with echinoid body size. Most relationships were rather weak, except in the cases of Pb and Fe in the non-calcified compartment and Cd in the calcified compartment. The allometric relationships were affected by seasonal factor in the non-calcified compartment only. The results indicate that biomonitoring programs using P. lividus as an indicator of metal contamination must take into account both echinoid size and season as source of metal concentration variations.