Heavy Metal Levels in Several Species of Marine Algae from the Red Sea of Saudi Arabia

Thirteen species of marine algae of Chlorophycophyta, Phaeophycophyta and Rhodophycophyta of the Red Sea coast of Saudi Arabia have been analysed for the heavy metals: Ag, AI, As, Cd, Co, Hg, Mo, Ni, Pb,Ti,andV. The heavy metal content of the thirteen species studied exhibited re- markable differences according to the species, but a certain range of con- centration appeared likely to be restricted to each division. The green species were characterized in having the highest proportions of Hg, Ni and Pb. In the brown species, largest amounts of AI, As, Ti and V were recorded. Most of metals in the red species were of moderate levels. Halimeda opuntia was found to have considerably higher levels of six of eleven metals investigated indicating that this species, rather than other species, is potentially a better source of these metals. This plant could, therefore, be used to monitor metal levels in water. The levels of Ag and Cd in all species were lower than those of other met- als investigated. High levels of AI and Hg were notable in the thirteen species.