Sponges and sediments as monitoring tools of metal contamination in the eastern coast of the Red Sea, Saudi Arabia

Sediments and sponges were collected from various locations along the eastern coast of the Red Sea, the Kingdom of Saudi Arabia. Total concentrations of Cd, Zn, Ag, Cu, Pb, As and Hg in the sediments were measured. Metal contamination was not significant in most of the studied sites and only one site was moderately polluted by Zn, Cu, and Pb. Sponges accumulated specific metals readily even though the metal exposure was low in the ambient environment. Contrasting interspecies differences in metal accumulation patterns were observed among the nine collected species of sponges. Significant positive correlations were found between the metal concentrations in the two species of sponges collected from the same sites. The strong ability to accumulate specific metals and the diversity of sponges that live in the Red Sea coastal areas make them a promising biomonitor of metal contamination in the areas.