CONCENTRATION AND SPECIATION OF ARSENIC IN MARINE MACRO-ALGAE

Arsenic concentration of marine algae varies significantly, ranging from an average of 10·3 μ g-1 in the Phaeophyceae to 1·54 μ g-1 in the Chlorophyceae and 1·43 μ g-1 in the Rhodophyceae. The chemical speciation is also significantly different, with the Phaeophyceae containing an average of 22% inorganic arsenic, and the Chlorophyceae and Rhodophyceae containing about 45% inorganic arsenic. The absolute concentration of inorganic arsenic is not significantly different between the classes, however, and may represent maximum tolerable levels for macro-algae. The variations in arsenic concentration are probably due to metabolic differences between classes, and not to differences in the amount of total available arsenic in the surrounding water. © 1979.