Sponges as Biomonitoring Tools: Insight into Heavy Metal Accumulation in Two Marine Sponges from the Atlantic and Mediterranean Coasts of Morocco

Aquatic ecosystems worldwide are exposed to various pollutants, including heavy metals, which are particularly dangerous due to their persistence, toxicity, and ability to accumulate in organisms. Due to their water filtration capacity and potential to accumulate heavy metals, marine sponges appear to be excellent candidates for biomonitoring marine environments. In this context, the present study investigated the potential of two demosponge species, Hymeniacidon perlevis and Suberites domuncula, as biomonitoring tools in Atlantic and Mediterranean Moroccan waters. The results of inductively coupled plasma optical emission spectroscopy (ICP-OES) showed a significant accumulation of heavy metals; Pb, As, Cd, Ni, and Cu in the species studied, with considerable inter- and intra-species variability. Specifically, S. domuncula from Al Hoceima showed the highest concentrations with 99.46µg/ g Cu and 4.06µg/ g As, while S. domuncula from Oued Laou contained 33.34µg/ g Cu, 2.85µg/ g As and 2.04µg/ g Pb. H. perlevis, on the other hand, showed a concentration of 10.54µg/ g Cu, 2.74µg/ g As and 2.24µg/ g Cd. Overall, the results of this study confirm that marine sponges are a valuable tool for biomonitoring studies. The results also suggest their use for monitoring water quality along Morocco's Mediterranean and Atlantic coasts.