Selective determination of inorganic arsenic(III), (V) and organic arsenic in marine organisms.

Abstract

Selective determination of inorganic arsenic (III), (V) and organic arsenic by the solvent extraction method was done with 20 species of marine organisms, including fish, ascidian, holo-thurian, sea urchin, crustacean, shellfish, cephalopod, polychaete, and seweed. In all species, inorganic arsenic, which is more highly toxic than organic arsenic, comprised only a small part (0-7%) of the total arsenic; the one exception was in a seaweed Hizikia fusiforme, in which inorganic arsenic accounted for 60% of the total arsenic. Furthermore, when arsenic in water-soluble and fat-soluble fractions was determined, the ratio of water-soluble arsenic reached 58-97% of the total arsenic. Especially in the cephalopod (3 species) and fish (6 species), more than 84% of the total arsenic was found in the water-soluble fraction. These results strongly suggested that most arsenicals in marine organisms are present in water-soluble organic forms.